TWI462307B - Photovoltaic cells of si-nanocrystals with multi-band gap and applications in a low temperature polycrystalline silicon thin film transistor panel - Google Patents

Description

Nanocrystalline crystal photocell with multiple energy gaps and its application in a low temperature polycrystalline germanium thin film transistor panel

The present invention relates generally to a photovoltaic cell, and more particularly to a photovoltaic cell having a photoelectric conversion layer having multiple energy gaps, and a low temperature polycrystalline silicon thin film transistor (LTPS-TFT) or amorphous germanium. Application in a thin film transistor (a-Si TFT, "amorphous silicon thin film transistor") panel.

A solar cell or photovoltaic cell belongs to a semiconductor device that converts solar/light energy into electrical energy using the photoelectric effect. Generally, a solar cell is configured as a large-area PN junction made of tantalum having a layer of N-type (negative) crucible and a P-type (positive type) in direct contact with the layer N-type crucible. Hey. When a photon strikes the solar cell, the photon can pass directly through the 矽 (if the photon has low light energy) or be reflected from the surface or absorbed by the ( (if the photon's light energy is higher than the 矽 energy gap value) . Depending on the frequency band structure of the solar cell, the latter produces an electron hole pairing and some heat. Due to the interface electric field of the P-N junction, the generated holes move toward the anode of the P-type germanium layer, and the generated electrons move toward the cathode on the N-type germanium layer in the germanium solar cell, thereby generating electrical energy.

Materials used for solar cells include germanium, III-V semiconductors (such as GaAs), II-VI semiconductors (such as CdS/CdTe), organic/polymer materials, and others. Among them, the most commonly developed are solar cells including single crystal germanium wafer type solar cells, polycrystalline silicon (poly-Si) thin film solar cells, and amorphous germanium (a-Si) thin film solar cells. III-V semiconductor solar cells are formed on germanium (Ge) substrates and have high efficiency, but are very expensive, so they are only used in satellite and integrated optics, because most of this cost is used in the Ge substrate. . In addition, III-V and II-VI semiconductor solar cells cannot be easily integrated with germanium-based CMOS and thin film transistor liquid crystal display (TFT-LCD) glass panels and low temperature polysilicon (LTPS) processing. Further, there is a problem of serious metal contamination when manufacturing III-V and II-VI semiconductor solar cells. Although the cost of amorphous germanium thin film solar cells is not high, efficiency and stability are not high. Therefore, silicon wafer solar cells have become the mainstay of the solar cell market.

Solar cells are energy conversion devices, so conversion efficiency is limited by the Camot Limit, which is about 85%. So far, the highest conversion efficiency achieved by solar cells on the market is about 33%. Therefore, there is room for improvement in the efficiency of such solar cells.

In theory, photons with energies below the energy gap of the absorbing material are not absorbed by the material to create an electron hole pairing so that their energy cannot be converted through the absorbing material. For photons with energies above the energy gap, only some of the energy above the energy gap can be converted into a useful electron hole paired output. When a more energetic photon is absorbed, excess energy above the energy gap is converted into kinetic energy of the carrier combination. These excessive kinetic energy is converted into heat through photon interaction as the kinetic energy of the carriers slows down to equilibrium speed. The solar spectrum is close to a blackbody spectrum of approximately 6000K, and most of the solar radiation reaching the Earth consists of photons with energy greater than the chirp energy gap. These higher energy photons will be absorbed by the solar cell, but the energy difference between these photons and the chirp gap will be converted into heat through lattice vibrations (phonons) rather than being converted into usable electrical energy. For a single bonded (single band gap) solar cell, the theoretical maximum conversion efficiency is approximately 28%. However, because the material cannot absorb all the essential limitations of photons whose energy is higher than the energy gap, and because the free carrier absorption of these materials limits the photon absorption to 100% conversion into electron hole pairing, Polycrystalline germanium (poly-Si) solar cells have an average conversion efficiency of only about 15%.

For multiple-junction (or multiple-gap) solar cells, individual single-junction solar cells are stacked (serially) in descending order of energy gap, and the top-most cells capture the high-energy photons and absorb them through lower-gap cells. The remaining photons. The use of multiple energy gaps (or multiple junctions) reduces the energy relationship between the bands, thus reducing the likelihood of photons being generated compared to a single junction (single band gap) solar cell, thereby reducing heat generation and improving the photoelectric conversion efficiency. However, such tandem solar cells have problems with joint loss and lattice mismatch.

Therefore, the problem to be solved in the technology to date is to solve the above defects and incompleteness.

Recently, because of the high photoelectric efficiency and the wavelength adjustability of nanostructured light absorption, attention has been focused on quantum dot solar cells, that is, third generation solar cells. For a solar cell using germanium, an indirect gap semiconductor has developed a quantum confinement effect using nanostructures. In order to obtain a crystalline or amorphous yttrium (a-Si) nanostructure of less than 5 nm, such as the quantum confinement effect of quantum wells, quantum wires, and quantum dots, it is necessary to use materials with energy levels greater than the 矽 energy level as a matrix (material substrate ) or barriers. I know that as the nanostructure size becomes smaller, the wavelength of light becomes shorter. Among these nanostructures, quantum dot structures have the advantage of high quantum efficiency.

For a quantum dot solar cell, the germanium quantum dots are usually embedded in a dielectric matrix such as yttrium oxide (SiOx), tantalum nitride (SiNy), tantalum carbide (SiCz), or the like. The germanium quantum dots provide a broad multiple energy gap (approximately 4.1 eV to 1.2 eV) structure.

One aspect of the invention relates to a photovoltaic cell or a solar cell. In a specific embodiment, the photovoltaic cell comprises a first conductive layer; an N-type doped semiconductor layer formed on the first conductive layer; and a first germanium layer formed on the N-type doped semiconductor layer; a nanocrystalline yttrium (nc-Si) layer formed on the first ruthenium layer; a second ruthenium layer formed on the nano crystallization layer; and a P-type doped semiconductor layer formed on the second ruthenium layer And a second conductive layer formed on the P-type doped semiconductor layer.

In a specific embodiment, one of the first tantalum layer and the second tantalum layer is formed of amorphous germanium (a-Si), and the other of the first tantalum layer and the second tantalum layer It is formed of polycrystalline silicon (poly-Si). The N-type doped semiconductor layer is formed of an N-type doped germanium, and here the P-type doped semiconductor layer is formed of a P-type doped germanium.

The nanocrystalline ruthenium layer has a plurality of ruthenium crystals having a crystal size ranging from about 1 to 20 nm.

At least one of the first conductive layer and the second conductive layer is formed of a transparent conductive material. The transparent conductive material may be indium tin oxide (ITO), indium zinc oxide (IZO), aluminum zinc oxide (AZO), cerium oxide (HfO), or a combination of these compounds.

In another aspect, the invention is directed to a method of making a photovoltaic cell. In a specific embodiment, the method comprises the steps of: providing a substrate; forming a first conductive layer on the substrate; forming an N-type doped semiconductor layer on the first conductive layer; and forming the N-type doped semiconductor on the first conductive layer; Forming a first germanium layer on the layer; forming a nanocrystalline germanium layer on the first germanium layer; forming a second germanium layer on the nanocrystalline germanium layer; forming a P-type doping on the second germanium layer a semiconductor layer; and a second conductive layer formed on the P-type doped semiconductor layer.

In a specific embodiment, the step of forming the nanocrystalline germanium layer comprises forming a germanium-rich (Si-rich) dielectric layer on the first germanium layer, and laser annealing the germanium-rich dielectric layer to form therein A plurality of nano crystals.

In a specific embodiment, the N-type doped semiconductor layer is formed of an N-type doped germanium, and here the P-type doped semiconductor layer is formed of a P-type doped germanium. The nanocrystalline ruthenium layer has a plurality of ruthenium crystals having a crystal size ranging from about 1 to 20 nm. One of the first layer and the second layer is formed of amorphous germanium, and the other is formed of polycrystalline germanium.

At least one of the first conductive layer and the second conductive layer is formed of a transparent conductive material. The transparent conductive material may be indium tin oxide (ITO), indium zinc oxide (IZO), aluminum zinc oxide (AZO), cerium oxide (HfO), or a combination of these compounds.

Another aspect of the invention relates to a photovoltaic cell. In a specific embodiment, the photovoltaic cell has a first conductive layer, a second conductive layer, and a photoelectric conversion layer, wherein the photoelectric conversion layer is formed between the first conductive layer and the second conductive layer. The photoelectric conversion layer has a multiple energy gap. At least one of the first conductive layer and the second conductive layer is formed of a transparent conductive material. In a specific embodiment, the photovoltaic cell further has an N-type doped semiconductor layer and a P-type doped semiconductor layer. An N-type doped semiconductor layer is formed between the first conductive layer and the photoelectric conversion layer, and a P-type doped semiconductor layer is formed between the second conductive layer and the photoelectric conversion layer.

In a specific embodiment, the photoelectric conversion layer comprises an amorphous germanium (a-Si) layer, a poly-Si layer, and a germanium-rich dielectric formed between the amorphous germanium layer and the poly germanium layer. Floor. The material of the combination of the ytterbium-rich dielectric layer may be a cerium-rich oxide, a cerium-rich nitride, a cerium-rich oxynitride, a cerium-rich carbide or a combination of these compounds. The ruthenium-rich dielectric layer comprises a nanocrystalline ruthenium layer having a plurality of ruthenium crystals, wherein the ruthenium crystal size is in the range of about 1-20 nm.

In another embodiment, the photoelectric conversion layer comprises a first germanium-rich dielectric layer formed on the first conductive layer and having a refractive index n1, and formed on the first germanium-rich dielectric layer and having a a second cerium-rich dielectric layer having a refractive index n2, wherein n2 < n1. In a specific embodiment, the photoelectric conversion layer may further include a third germanium-rich dielectric layer formed between the second germanium-rich dielectric layer and the second conductive layer and having a refractive index n3, wherein n3<n2 <n1. The constituent materials of each of the first ruthenium-rich dielectric layer, the second ruthenium-rich dielectric layer, and the third ruthenium-rich dielectric layer may be cerium-rich oxide, cerium-rich nitride, cerium-rich oxynitride, ore-rich carbide or A combination of these compounds. In other embodiments, the photoelectric conversion layer also includes an amorphous germanium layer and a poly germanium layer, and the first germanium-rich dielectric layer and the second germanium-rich dielectric layer are formed between the amorphous germanium layer and the poly germanium layer. .

Another aspect of the invention relates to a method of making a photovoltaic cell. In a specific embodiment, the method includes: providing a substrate; forming a first conductive layer on the substrate; forming a photoelectric conversion layer on the first conductive layer, wherein the photoelectric conversion layer has a multiple energy gap; And the steps of forming a second conductive layer on the photoelectric conversion layer.

In addition, the method also includes the steps of forming an N-type doped semiconductor layer between the first conductive layer and the photoelectric conversion layer, and forming a P-type doped semiconductor layer between the second conductive layer and the photoelectric conversion layer. .

In a specific embodiment, the step of forming the photoelectric conversion layer includes forming a first germanium layer on the first conductive layer, forming a germanium rich interposer layer on the first germanium layer, and forming on the germanium rich dielectric layer. A second layer of enamel. One of the first layer and the second layer includes an amorphous layer and the other includes a polysilicon layer. The step of forming the germanium-rich dielectric layer further includes laser annealing the germanium-rich dielectric layer to form a plurality of germanium crystals therein.

In another embodiment, the step of forming the photoelectric conversion layer includes forming a first germanium-rich dielectric layer on the first conductive layer and having a refractive index n1, and forming on the first germanium-rich dielectric layer And having a second ytterbium-rich dielectric layer having a refractive index n2. In a specific embodiment, the step of forming the photoelectric conversion layer further includes forming a third germanium-rich dielectric layer between the second germanium-rich dielectric layer and the second conductive layer and having a refractive index n3, wherein n3 <n2<n1.

Another aspect of the invention relates to a liquid crystal display panel (LCD panel) that is operatively operable by a liquid crystal display driver and that can be illuminated by a backlight. In a specific embodiment, the liquid crystal display panel has a display area for displaying related information, and a photocell placed in an area surrounding the display area and exposed to a light to convert the optical energy of the light. The electric energy is supplied to the liquid crystal display driver as a driving power. The photovoltaic cell includes a first conductive layer, a second conductive layer, and a photoelectric conversion layer formed between the first conductive layer and the second conductive layer, wherein the photoelectric conversion layer has a multiple energy gap. In one embodiment, the display region has a plurality of low temperature polycrystalline silicon thin film transistors (LTPS-TFTs) or amorphous silicon thin film transistors (a-Si TFTs, "amorphous silicon thin" Film transistor").

In a specific embodiment, the photoelectric conversion layer comprises an amorphous germanium layer, a poly germanium layer, and a germanium-rich dielectric layer formed between the amorphous germanium layer and the poly germanium layer. The ytterbium-rich dielectric layer is formed of a material comprising a cerium-rich oxide, a cerium-rich nitride, a cerium-rich oxynitride, a cerium-rich carbide, or a combination thereof. In one embodiment, the ruthenium-rich dielectric layer comprises a nanocrystalline ruthenium layer having a plurality of ruthenium crystals having a crystal size ranging from about 1 to 20 nm.

In other embodiments, the photoelectric conversion layer comprises a first ytterbium-rich dielectric layer formed on the first conductive layer and having a refractive index n1, and formed on the first ytterbium-rich dielectric layer and having a refraction A second bismuth-rich dielectric layer of rate n2, where n2 < n1. The photoelectric conversion layer may further have a third germanium-rich dielectric layer formed between the second germanium-rich dielectric layer and the second conductive layer and having a refractive index n3, where n3 < n2 < n1.

One aspect of the invention relates to a method of fabricating a liquid crystal display panel that can be driven by a liquid crystal display driver and that can be illuminated by a backlight. In one embodiment, the method includes: providing a substrate; forming a display area on the substrate; and forming a photocell in the area surrounding the display area on the substrate and exposing it to a light. Thus, when the optical energy of the light is received, the photovoltaic cell converts the optical energy into an electrical energy that is supplied to the liquid crystal display driver as a driving power. The step of forming the photovoltaic cell includes: forming a first conductive layer; forming a second conductive layer; and forming a photoelectric conversion layer between the first conductive layer and the second conductive layer, wherein the photoelectric conversion layer has a multiple energy Gap.

In a specific embodiment, the step of forming the photoelectric conversion layer comprises forming a first germanium layer on the first conductive layer, forming a germanium-rich dielectric layer on the first germanium layer, and enriching the laser in the laser annealing A second layer of germanium is formed on the dielectric layer. One of the first layer and the second layer includes an amorphous layer and the other includes a polysilicon layer. In a specific embodiment, the step of forming the germanium-rich dielectric layer further comprises laser annealing the germanium-rich dielectric layer to form a plurality of germanium crystals therein.

In other embodiments, the step of forming the photoelectric conversion layer includes forming a first germanium-rich dielectric layer on the first conductive layer and having a refractive index n1, and forming on the first germanium-rich dielectric layer A second ytterbium-rich dielectric layer having a refractive index n2. Further, the step of forming the photoelectric conversion layer further has a third germanium-rich dielectric layer formed between the second germanium-rich dielectric layer and the second conductive layer and having a refractive index n3, wherein n3 < n2 < n1.

Another aspect of the invention relates to a display panel having a plurality of pixels arranged in a matrix. Each pixel includes an active area for displaying related information, a switching area having one or more switching elements, and a photovoltaic cell formed between the active area and the switching area, wherein the photovoltaic cell has a multiple energy The photoelectric conversion layer of the gap.

In a specific embodiment, the photoelectric conversion layer comprises an amorphous germanium layer, a poly germanium layer, and a germanium-rich dielectric layer formed between the amorphous germanium layer and the poly germanium layer. The ruthenium-rich dielectric layer comprises a nanocrystalline ruthenium layer having a plurality of ruthenium crystal sizes ranging from about 1 to 20 nm.

Another aspect of the invention relates to a method of manufacturing a display panel. In a specific embodiment, the method includes: providing a substrate; and forming a plurality of pixels in a matrix on the substrate. Each of the pixels includes a photocell having a photoelectric conversion layer having a plurality of energy gaps.

In a specific embodiment, the method of forming the plurality of pixels includes the steps of: (a) forming a plurality of gates electrically coupled to the gate lines of the substrate, the plurality of gates being spatially separated from each other, and each An active area, a switching area, and a photocell are defined between a pair of adjacent gates. (b) forming a gate insulating layer on the plurality of gates and the remaining region of the substrate; (c) forming an amorphous germanium layer on the gate insulating layer and covering each gate in each switching region (d) forming a doped amorphous germanium layer on the amorphous germanium layer; (e) forming a first conductive layer on the doped amorphous germanium layer and remaining regions of the gate insulating layer; (f) placing a ruthenium-rich dielectric layer covering each photocell region on the first conductive layer; (g) forming a source and a drain in each of the switching regions, thereby forming a field effect on the substrate An array of transistors; (h) forming a passive layer overlying the field effect transistor array and the germanium-rich dielectric layer on the first conductive layer; (i) channel contact and in the switching region and the photocell region And (j) forming a second conductive layer having a first portion on a region between the switching region and the photovoltaic cell region, such that the first portion contacts the field effect through the channel in each switching region a drain of the transistor and a second portion of the fused dielectric layer in contact with the photocell region.

The step of forming the plurality of pixels further includes laser annealing the germanium-rich dielectric layer to form a plurality of germanium crystals therein.

In a specific embodiment, the gate insulating layer is formed of hafnium oxide, tantalum nitride or hafnium oxynitride. The doped amorphous germanium layer comprises an n+ doped amorphous germanium or a p+ doped amorphous germanium. A dielectric material forming the passive layer may comprise hafnium oxide or tantalum nitride. At least one of the first conductive layer and the second conductive layer is transparent. In a specific embodiment, the second conductive layer may be formed of indium tin oxide (ITO), indium zinc oxide (IZO), aluminum zinc oxide (AZO), hafnium oxide (HfO), or a combination of these compounds.

These and other aspects of the invention will be apparent from the following description of the preferred embodiments of the invention.

The invention will be described in more detail in the following description of the examples, and many modifications and variations will be apparent to those skilled in the art. Many specific embodiments of the invention are described in detail herein. Please refer to the drawings, in which like numerals indicate like components. The use of the terms "a", "an" and "the" In addition, the meaning of "middle" includes "middle" and "above" as used herein and as used throughout the claims. In addition, there are more specific definitions of certain terms used in this specification.

As used herein, "about" or "about" generally means within 20 percent of the known value or range, preferably within 10 percent, and more preferably within 5 percent. The quantity given is an approximate value, which means that if it is not clearly indicated, it can be inferred to be "about" or "about".

As used herein, "solar cell" and "photocell" as used in this specification are synonymous, and means a device that converts solar energy/light energy into electric power by the photoelectric effect.

Many abbreviations and abbreviations are used here. "nc-Si" is a nanocrystal, "a-Si" is amorphous, "poly-Si" is polycrystalline, "Si-rich" is rich, and "LTPS" is Low-temperature polysilicon, "TFT" is a thin film transistor, "PECVD" is plasma-enhanced chemical vapor deposition, "ELA" is excimer laser annealing, and "CLC" is continuous-wave laser crystallization.

Specific embodiments of the present invention will be described in detail herein with reference to FIGS. 1 through 14. In accordance with the purpose of the present invention, as embodied and broadly described herein, in one aspect, the present invention is directed to a photovoltaic cell having a multi-band gap and a low-energy gap and its low temperature Applications in polycrystalline germanium thin film transistor (LTPS-TFT) panels.

Referring to Figure 1, there is shown a photovoltaic cell 100 in accordance with an embodiment of the present invention. In this exemplary embodiment, the photovoltaic cell 100 has a first conductive layer 110, a germanium-rich dielectric layer 140 formed on the first conductive layer 110, and a second conductive layer formed on the germanium-rich dielectric layer 140. Layer 170. The ruthenium rich dielectric layer 140 can be deposited by PECVD. In the cerium-rich dielectric deposition process, the ratio of tetrahydrogen hydride (SiH4) to nitrous oxide (N2O) (or ammonia NH3 or nitrogen N2) gas is adjusted to obtain a desired refractive index range. Among them, the range of the refractive index indicates the degree of enrichment of ruthenium in the film. The excess germanium atoms in the germanium-rich dielectric layer 140 are separated, aggregated, and converted into nanocrystals by appropriate laser annealing to form a nanocrystalline crystalline germanium dielectric layer (nanocrystalline germanium layer). Thus, a germanium-rich dielectric layer of germanium crystals 145 having different refractive indices (1.6-3.7), different thicknesses (50-500 nm), and different sizes (1-20 nm) can be fabricated. Due to the change of the melting point of different semiconductor materials and the energy absorption efficiency level, a plurality of laser-inducing nanocrystals can also be formed by using a laser crystal polycrystalline germanium or an amorphous germanium film. Thus, the laser crystallization process constructs a multiple energy gap light absorbing structure that allows the photovoltaic cell 100 to absorb light having a wavelength in the range of about 300-1000 nm.

The lanthanum-rich dielectric layer 140 is formed of a combination of materials containing cerium-rich oxide (SiOx), cerium-rich nitride (SiNy), cerium-rich oxynitride (SiOxNy), cerium-rich carbide (SiCz), or the like, wherein 0<x<2, 0<y<1.34 and 0<z<1. The ruthenium-rich dielectric layer 140 can be formed in a single layer or a multilayer structure. Regardless of the single layer or multilayer structure, the germanium-rich dielectric layer 140 includes at least one of a germanium-rich oxide film, a germanium-rich nitride film, and a germanium-rich oxynitride film.

The first conductive layer 110 and the second conductive layer 170 may be formed of a metal, a metal oxide, or any combination of these materials. The material may be a refractive material comprising any combination of aluminum, copper, silver, gold, titanium, molybdenum, lithium, niobium, tantalum, tungsten, alloys, other or a laminate or alloy of these materials. The metal oxide may be a transparent conductive material, and includes indium tin oxide (ITO), indium zinc oxide (IZO), aluminum zinc oxide (AZO), hafnium oxide (HfO), or the like. The material can be a combination of the refractive materials and the transparent conductive materials. In practice, at least one of the first conductive layer and the second conductive layer is made of a transparent conductive material such as ITO, IZO, AZO, HfO, or the like. The transparent conductive material allows ambient light to penetrate and reach the ytterbium-rich dielectric layer (photosensitive region).

In effect, an interlayer dielectric layer (UHA layer) 180 is formed over the germanium-rich dielectric layer 140. A patterning/masking process is then applied to the UHA layer 180 to define the channels or contact holes 181 therein. The second conductive layer 170 is formed on the germanium-rich dielectric layer 140 through the via or contact hole 181.

Compared to conventional multi-junction (serial) photovoltaic cells having individual single-bonded photovoltaic cells stacked in a decreasing order of energy, a single-junction multiple energy gap Si nanocrystalline photovoltaic cell has many advantages. Within the multi-junction unit device, the top unit captures the high energy photons and allows the remaining photons to be absorbed by the lower energy gap unit to pass. However, such tandem photovoltaic cells contain the disadvantage of joint loss and lattice mismatch, thus reducing the photoelectric conversion efficiency. Photovoltaic cells with multiple energy gap absorbing materials can convert the solar spectrum more efficiently. By using multiple energy gaps, the solar spectrum can be divided into smaller fractions where thermodynamic efficiency is more restrictive for each part.

Figure 2 illustrates a process for fabricating a photovoltaic cell 200 in accordance with an embodiment of the present invention. First, as shown in FIG. 2A, a germanium-rich dielectric layer 240 is formed on a first conductive layer 210. Next, the germanium-rich dielectric layer 240 is exposed to the beam of laser 292 to form a plurality of nanocrystals 245 therein, as shown in FIG. 2B. Then, a second conductive layer 270 is formed over the germanium-rich dielectric layer 240 as shown in FIG. 2C.

A ruthenium-rich dielectric layer can be formed on the first conductive layer 210 by a plasma enhanced chemical vapor deposition (PECVD) process at a low pressure of about 1 torr at a temperature below about 400 °C. 240. In one embodiment, the germanium-rich dielectric layer 240 can be formed at a temperature in the range of about 200 ° C to 400 ° C or about 350 ° C to 400 ° C, preferably at about 370 ° C. For a known temperature range, it takes from about 13 seconds to 250 seconds, preferably from about 25 seconds to 125 seconds, to form a ytterbium-rich dielectric layer 240 having a desired thickness of from about 50 nanometers (nm) to about 1000 nm. During the process of forming the germanium-rich dielectric layer 240, the refractive index of the germanium-rich dielectric layer 240 can be controlled by adjusting the germanium-containing ratio SiH4/N2O. In a specific embodiment, the cerium-containing ratio SiH4/N2O is adjusted in the range of from about 1:10 to about 10:1, resulting in a refractive index at least in the range of from about 1.47 to about 3.7, and the cerium-containing ratio is preferably about In the range of 1:5 to about 10:1, the refractive index is caused to be at least in the range of about 1.7 to about 3.7. The ruthenium rich dielectric layer 240 can also be formed by other methods or processes.

Laser annealing of the germanium-rich dielectric layer 240 can be accomplished, for example, by using excimer laser annealing (ELA). Excimer lasers with adjustable frequencies and adjustable laser power densities can be utilized at temperatures below 400 °C. In a specific embodiment, the ELA is performed at a pressure of about 1 atmosphere (760 Torr) or about 1 x 103 Pa at a temperature below about 400 °C. In other embodiments, the ELA is performed at room temperature, i.e., about 20-25 °C. Other types of laser annealing with corresponding parameters can also be used to practice the invention.

The laser wavelength and the laser power level can be adjusted to produce the desired laser induced nanocrystal diameter. For any laser type, such as, for example, ELA, "continuous-wave laser crystallization" (CLC), solid state CW green laser, etc., the laser wavelength is in the range of about 266-1024 nm. The desired laser-induced 矽 nanocrystals have a diameter in the range of about 1-20 nm, preferably in the range of about 3-6 nm. In one embodiment, the ELA of the germanium-rich dielectric layer 240 is performed at a wavelength in the range of about 266-532 nm, preferably about 308 nm. The ELA of the germanium-rich dielectric layer 240 is typically performed over a range of laser power intensities of about 70-440 mJ/cm2, preferably in the range of laser power intensities of about 70-200 mJ/cm2. In other embodiments, the CLC of the germanium-rich dielectric layer 240 is performed over a range of wavelengths, for example, about 532-1024 nm. In other embodiments, the solid state CW green laser of the germanium-rich dielectric layer 240 is performed over a range of wavelengths, such as about 532 nm. However, when the laser power intensity exceeds about 200 mJ/cm 2 , the first conductive layer under the germanium-rich dielectric layer 240 may be damaged or peeled off. In order to produce a germanium-rich dielectric layer 240 having a large laser-induced nanocrystal ranging from about 4 nm to about 10 nm, the excimer laser annealing of the germanium-rich dielectric layer 240 is preferably at a laser power intensity of about 200. Executed on the range of -440mJ/cm2. In another aspect, to produce a germanium-rich dielectric layer 240 having a smaller laser-induced nanocrystal having a range of from about 2 nm to about 6 nm, the ELA of the germanium-rich dielectric layer 240 is preferably at a laser power intensity. Executed on the range of 70-200 mJ/cm2. The density of the laser-induced nanocrystals 245 in the germanium-rich dielectric layer 240 is preferably in the range of from about 1 x 1011 /cm2 to about 1x1012 / cm2.

Figure 3 shows the characteristics of a laser-induced nanocrystal: (A) a transmission electron microscopy (TEM) image showing the size of the nanocrystals, and (B) a peak with a diameter of about 4 nm. Laser-induced distribution of nanocrystal size in nanocrystals.

Referring back to Figure 2C, in this embodiment, the second conductive layer 270 is transparent. When the incident beam of light 295 passes through the transparent layer 270 and reaches the germanium-rich dielectric layer 240 having a plurality of laser-induced nanocrystals 245, it absorbs multiple energy gaps having energy equal to or greater than the germanium-rich dielectric layer 240. Beam photons. Therefore, a hole (h+) and an electron (e-) pair are generated in the rich dielectric layer 240. The generated holes (h+) and electrons (e-) are directed toward and through the second conductive layer 270 and the first conductive layer 210, respectively. If a load connects the first conductive layer 210 and the second conductive layer 270, a current will flow through the load. That is, the photon energy of the incident light 295 is converted into electrical energy by the photocell 200.

Further, the first conductive layer 210 may also be made of a transparent conductive material.

The steps disclosed above do not need to be performed in order, and the process is not the only way to implement the invention.

For example, a photovoltaic cell can be fabricated by providing a substrate, forming a first conductive layer on the substrate, forming a germanium-rich dielectric layer on the first conductive layer, and forming a second conductive layer on the germanium-rich dielectric layer. Then, the ruthenium-rich dielectric layer is subjected to laser annealing to form a plurality of ruthenium crystals. In a specific embodiment, the laser annealing is performed by directing a laser beam from the top end of the second conductive layer to the germanium rich dielectric layer. In other embodiments, the substrate and the first conductive layer are made of a transparent conductive material such that the laser annealing is performed by directing a laser beam from the bottom of the substrate to the germanium-rich dielectric layer. In an alternative embodiment, the laser annealing is performed by directing two laser beams from the top and bottom of the photovoltaic cell to the ytterbium-rich dielectric layer, respectively.

Referring to Figure 4, there is shown a photovoltaic cell battery 400 in accordance with an embodiment of the present invention. Photovoltaic battery pack 400 includes a photocell 401 for converting photon energy of light 495 incident on photovoltaic cell 401 into electrical energy. The photocell 401 has a first conductive layer 410, a second conductive layer 470, and a germanium-rich dielectric layer 440 formed between the first conductive layer 410 and the second conductive layer 470. The ruthenium-rich dielectric layer 440 has a plurality of laser-induced nanocrystals 445 having a multiple energy gap. Furthermore, the photovoltaic cell stack 400 also includes a rechargeable battery pack 480 electrically coupled between the first conductive layer 410 and the second conductive layer 470 for storing electrical energy. Further, an ammeter 485 is connected between the photocell 401 and the rechargeable battery 480. The photovoltaic cell 401 can be manufactured by the above process.

Further, in place of the rechargeable battery 480 using a load, such as a resistor, the configuration as shown in Fig. 4 can also be used as a light sensor.

Referring to FIG. 5, a curve 510 is a spectral response of a photocell having a Si nanocrystal SiOx photoelectric conversion (photosensitive) layer to an incident light beam of white light, such as sunlight. The white photon reaction characteristic (400-650 nm) of the photovoltaic cell is derived from the multiple energy gap of the Si nanocrystal of the photovoltaic cell.

Figure 6 shows the photoluminescence reaction of a photocell to incident white light using different laser annealing power intensities on a Si-rich SiOx layer. Curves 610, 620, 630, and 640 are photoluminescence reactions of laser energies of 300 mJ/cm2, 350 mJ/cm2, 400 mJ/cm2, and 440 mJ/cm2, respectively.

Referring to Figure 7, there is shown the current-voltage characteristics of a photovoltaic cell in accordance with an embodiment of the present invention. Curves 710 and 720 are the dark current and photocurrent of the photovoltaic cell, respectively. This photoelectric characteristic indicates that a higher sensitivity than a conventional P-I-N (positive-inherent-negative) diode and a comparable dark current level can be easily obtained in the developed photocell.

Figure 8 illustrates the spectral characteristics of a photovoltaic cell having a multiple energy gap in accordance with an embodiment of the present invention. The multiple energy gap is divided into a plurality of narrow regions, each corresponding to a range of wavelengths of light to be photoelectrically converted into electrical energy.

Referring to Figure 9, a cross-sectional view of a photovoltaic cell 900 in accordance with an embodiment of the present invention is shown. In a specific embodiment, a photovoltaic cell 900 has a first conductive layer 910, a first semiconductor layer 920 formed on the first conductive layer 910, and a first fused dielectric formed on the first semiconductor layer 920. a layer 930, a second germanium-rich dielectric layer 940 formed on the first germanium-rich dielectric layer 930, a second semiconductor layer 960 formed on the second germanium-rich dielectric layer 940, and a second semiconductor A second conductive layer 970 on layer 960.

In one embodiment, one of the first semiconductor layer 920 and the second semiconductor layer 960 is an N-type doped semiconductor layer, and the first semiconductor layer 920 and the second semiconductor layer 960 are another P-type doped semiconductor layer. For example, the first semiconductor layer 920 is an N-type doped semiconductor layer, and the second semiconductor layer 960 is a P-type doped semiconductor layer. The N-type doped semiconductor layer includes an N-type doped germanium, and the P-type doped semiconductor layer includes a P-type doped germanium. Other semiconductor materials can also be used to implement the invention. The N-type doped semiconductor layer 920 and the P-type doped semiconductor layer 960 can be formed by a standard process such as an implant process and a PECVD process.

In other embodiments, one of the first semiconductor layer 920 and the second semiconductor layer 960 is formed of amorphous germanium and the other is formed of polysilicon. For example, the first semiconductor layer 920 is formed of polysilicon, and the second semiconductor layer 960 is formed of amorphous germanium. The first conductive layer 920 and the second conductive layer 960 may be formed of microcrystalline germanium, single crystal germanium, or any combination of these materials. The laser crystallized N-type semiconductor and the laser crystallized P-type semiconductor are formed by a laser crystallization process.

The first germanium-rich dielectric layer 930 has a refractive index n1, and the second germanium-rich dielectric layer 940 has a refractive index n2, where n2 < n1. At least one of the first ruthenium-rich dielectric layer 930 and the second ruthenium-rich dielectric layer 940 has a plurality of ruthenium crystals having a multiple energy gap. A plurality of nanocrystals can be formed by a laser annealing treatment or a CVD treatment as described above. The first germanium-rich dielectric layer 930 and the second germanium-rich dielectric layer 940 may be formed of the same material or substantially different materials, such as germanium-rich oxides, germanium-rich nitrides, germanium-rich oxynitrides, and the like. . In one embodiment, the first germanium-rich dielectric layer 930 and/or the second germanium-rich dielectric layer 940 is a nanocrystalline germanium layer (nanocrystalline germanium-rich dielectric layer) having a multiple energy gap.

The first conductive layer 910 and the second conductive layer 970 may be formed of a metal, a metal oxide, or any combination of these materials. The material can be a refractive material comprising aluminum, copper, silver, gold, titanium, molybdenum, lithium, niobium, tantalum, tungsten, alloys, other or any combination of these materials. The metal oxide may be a transparent conductive material including ITO, IZO, AZO, HfO, and the like. The material can be a combination of a refractive material and a transparent conductive material. In practice, at least one of the first conductive layer and the second conductive layer is made of a transparent conductive material such as ITO, IZO, AZO, HfO or the like. In this embodiment, the second conductive layer 970 is preferably a transparent conductive material layer made of a transparent conductive material.

Figure 10 shows a photovoltaic cell 1000 in accordance with an embodiment of the present invention. In a specific embodiment, the photovoltaic cell 1000 includes a first conductive layer 1010, an N-type doped semiconductor layer 1020 formed on the first conductive layer 1010, and a photoelectric conversion layer formed on the N-type doped semiconductor layer 1020. 1001, a P-type doped semiconductor layer 1060 on the photoelectric conversion layer 1001 and a second conductive layer 1070 on the P-type doped semiconductor layer 1060.

The N-type doped semiconductor layer 1020 includes an N-type doped germanium, and the P-type doped semiconductor layer 1060 includes a P-type doped germanium.

The photoelectric conversion layer 1001 includes a plurality of nano crystals having a multiple energy gap. In a specific embodiment, the photoelectric conversion layer 1001 includes a single layer having the multiple energy gaps. The monolayer is formed of a nanocrystalline ruthenium having a plurality of nanocrystals having a multiple energy gap. In other embodiments, the photoelectric conversion layer 1001 includes a multilayer structure having at least one of a plurality of layers of nanocrystals having a multiple energy gap.

With respect to the multilayer structure, in one embodiment, the photoelectric conversion layer 1001 has a first germanium-rich dielectric layer 1030 formed on the N-type doped semiconductor layer 1020, and a first germanium-rich dielectric layer 1030. The second ytterbium-rich dielectric layer 1040 and the third ytterbium-rich dielectric layer 1050 formed on the second ytterbium-rich dielectric layer 1040. Each of the first germanium-rich dielectric layer 1030, the second germanium-rich dielectric layer 1040, and the third germanium-rich dielectric layer 1050 respectively have a corresponding refractive index n1, n2, and n3, where n3 < n2 < n1. In an alternate embodiment, the first ruthenium-rich dielectric layer 1030 and the third ruthenium-rich dielectric layer 1050 can be exchanged. In a specific embodiment, each of the first germanium-rich dielectric layer 1030, the second germanium-rich dielectric layer 1040, and the third germanium-rich dielectric layer 1050 comprise a germanium-rich oxide, a germanium-rich nitride, and a germanium-rich nitrogen. Oxide, cerium-rich carbide or a combination of these. After the photoelectric conversion layer 1001 is formed, a laser annealing treatment may be applied to the photoelectric conversion layer 1001 to form one or more layers of a plurality of laser-induced nanocrystals having a multiple energy gap. In a modified embodiment, a first semiconductor layer 920 (not shown) may be formed between the N-type doped semiconductor layer 1020 and the multilayer structure, and the second semiconductor layer 960 may be formed in a multilayer structure and P-type doped. Between the semiconductor layers 1060.

In other embodiments, the photoelectric conversion layer 1001 has a first germanium layer 1030 formed on the N-type doped semiconductor layer 1020, a nanocrystalline germanium layer 1040 formed on the first germanium layer 1030, and formed on The second hazel layer 1050 on the nanocrystalline hazelnut layer 1040. Of the first die layer 1030 and the second die layer 1050, one of them is formed of amorphous germanium, and the other is formed of polycrystalline germanium. Therefore, the photoelectric conversion layer 1001 has a multiple energy gap, a-Si/Si nanocrystal/poly-Si layered structure.

The first conductive layer 1010 and the second conductive layer 1070 may be formed of a metal, a metal oxide, or any combination of these materials. The material can be a refractive material comprising aluminum, copper, silver, gold, titanium, molybdenum, lithium, niobium, tantalum, tungsten, alloys, other or any combination of these materials. The metal oxide may be a transparent conductive material including ITO, IZO, AZO, HfO, or the like. The material can be a combination of a refractive material and a transparent conductive material. In practice, at least one of the first conductive layer and the second conductive layer is made of a transparent conductive material such as ITO, IZO, AZO, HfO, or the like.

The photovoltaic cell of the present invention can find many applications in a wide spectrum of fields, such as a light sensor, a display panel including a touch panel, and a non-volatile memory device.

Referring to FIG. 11A, a display panel 1101 integrated with one or more photovoltaic cells (photoreceptors) 1140 is shown in accordance with an embodiment of the present invention. The display panel 1101 includes a display area 1110 for displaying related information, and one or more photocells 1140 placed in the area around the display area 1110 and exposed to light. The one or more photovoltaic cells 1140 each have a germanium-rich dielectric layer having a nanocrystal having a multiple energy gap, and the cell is adapted to convert light energy into electrical energy. The light energy can be received from the backlight and/or ambient light.

The display panel 1101 may also include a display area 1120 for displaying information and receiving a user input, a light sensor 1130 for detecting light, and a surrounding light sensor 1150 for detecting ambient light. Each of these has at least a germanium-rich dielectric layer of nanocrystals.

The light sensor 1130 and the ambient light sensor 1150 can be placed in any corner area to detect ambient light or other light. One or more photocells 1140 can be positioned around the display area 1110 to convert the received light into electrical energy to conserve power consumed by the display panel 1101.

The display panel 1101 can be a touch panel or a liquid crystal display panel.

FIG. 11B is a diagram showing a liquid crystal display driver 1160 for driving a liquid crystal display panel 1102 and a backlight 1170 for illuminating the liquid crystal display panel 1102. The liquid crystal display panel 1102 includes a display area 1110 for displaying related information, and one or more photocells 1140 placed in the area around the display area 1110 and exposed under the backlight 1170. The one or more photovoltaic cells 1140 each comprise a multilayer structure having a germanium-rich dielectric layer of germanium crystals, and the cell is adapted to convert light energy into electrical energy. The light energy can be received from the backlight and/or ambient light. This electric energy is supplied to the liquid crystal display driver 1160 as driving power.

The method disclosed in the present invention can be used to fabricate a photovoltaic layer of a light-emitting device and/or a photosensitive layer of a light-sensing device using a high-efficiency laser annealing at a low temperature. The laser-induced nanocrystals fabricated in accordance with embodiments of the present invention within the dielectric layer exhibit high density, fairly uniform and uniform laser-induced nanocrystal distribution, and uniform laser-induced nanocrystals. diameter. These methods utilize low temperature excimer laser annealing treatment. This treatment does not require high temperature post annealing and is compatible with conventional processing for the production of Low-Temperature Poly-Si Thin Film Transistors (LTPS-TFT). A germanium-rich dielectric layer having a laser-induced nanocrystal fabricated in accordance with many embodiments of the present invention is quite useful for solar cells, touch panels, ambient light sensors, light sensors, and also with a color Quality field effect transistor (TFT) panel display integration. Laser-induced nanocrystals fabricated in accordance with many embodiments of the present invention can also be used as storage nodes in non-volatile memory devices with high retention, high durability, and high operating speed.

Figure 12 illustrates a low temperature polysilicon (LTPS) panel 1200 integrated with a photovoltaic cell (or photoreceptor) in accordance with an embodiment of the present invention. The low temperature polysilicon panel 1200 can have a plurality of pixels arranged in a matrix form. In Fig. 12, only the pixels of a low temperature polysilicon panel 1200 are illustrated. In this embodiment, each pixel has a display field effect transistor 1221 and a photocell 1201 formed on the display field effect transistor 1221.

The photocell 1201 has a three-layer stack structure including a first conductive layer 1230, a second conductive layer 1270, and a germanium-rich dielectric layer 1240 formed between the plurality of germanium crystals 1245.

The field effect transistor 1220 is formed on the substrate 1210. The field effect transistor 1221 has a source region 1222 (electrically coupled to the first conductive layer 1230 of the photovoltaic cell 1201), a drain region 1224, and a gate electrode 1226. The drain region 1224 (source region 1222) and the gate electrode 1226 are separated by a gate insulating layer 1220 formed on the substrate 1210. The substrate 1210 can be formed as a transparent substrate, such as a glass substrate, or an elastic substrate, such as a plastic substrate.

When such a photovoltaic cell 1201 is utilized within a display panel 1200, the photovoltaic cell 1201 is configured to face ambient light 1295. In addition, a backlight 1296 is typically used to illuminate the display panel 1200 to display information thereon. In order to prevent the backlight 1296 from deflecting the output of the photocell 1201, the first conductive layer 1230 is utilized to effectively block the backlight 1296.

In one embodiment, the germanium-rich dielectric layer 1240 of the photovoltaic cell 1201 is made of a cerium-rich oxide, a cerium-rich nitride, a cerium-rich oxynitride, a cerium-rich carbide, or the like. The cerium-rich oxide layer preferably has a refractive index in the range of about 1.7 to 3.7, and the cerium-rich nitride layer preferably has a refractive index in the range of about 1.7 to 3.7. At least some of the nanocrystals preferably have a diameter in the range of about 2-10 nm. The thickness of the ytterbium-rich dielectric layer 1240 is in the range of about 50-500 nm. The density of the laser-induced nanocrystals is preferably in the range of about 1 x 1011-1 x 1012 /cm2. The second conductive layer 1270 is preferably made of a transparent conductive material such as ITO, IZO, AZO, HfO or the like.

As shown in Fig. 12, the fill factor of the nanocrystal unit is much higher than that of the conventional unit because the photovoltaic cell 1201 is formed to cover the larger switching region where the field effect transistor 1221 is placed. Further, the metal electrode 1230 can provide effective ambient light and the backlight to separate the unit circuit from the photocell 1201, such that the transistor characteristics are more stable than in a P-I-N unit.

Referring to Figure 13, there is shown a low temperature polysilicon panel 1300 integrated with a photovoltaic cell (or photoreceptor) in accordance with an embodiment of the present invention. In this embodiment, each pixel has a field transistor 1301, a storage capacitor 1303, a photoreceptor 1305, and an active region 1307 formed adjacent to each other on the substrate 1310. The photoreceptor 1305 includes a first electrode 1355, a second electrode 1375, and a germanium-rich dielectric layer 1365 formed therebetween. The process of fabricating an amorphous germanium field effect transistor (a-Si TFT) panel 1300 in one embodiment is illustrated in FIG.

Referring to Figures 14A through 14F, an amorphous germanium field effect transistor panel fabrication method 1400 for integrating photovoltaic cells (photoreceptors) is illustrated in accordance with an embodiment of the present invention. The method includes the following steps: First, a first substrate 1410 is provided. The first substrate 1410 is formed of glass or the like. Then, a plurality of gate electrodes 1420 separated from each other are formed on the first substrate 1410, and the gate electrodes 1420 are electrically coupled to a gate line. The step of forming a plurality of gate electrodes 1420 is performed by first depositing a metal layer on the substrate 1410 by sputtering; masking the metal layer at an appropriate position to define the plurality of gate electrodes 1420; and then allowing the uncovered metal The remaining portion of the layer is exposed; the uncovered portion of the metal layer is etched away; and the mask portion is removed to form a plurality of gate electrodes 1420. Each pair of adjacent gate electrodes 1420 defines a switching region 1412 and a solar cell region 1414 therebetween. Solar cell region 1414 is adjacent to switching region 1412, wherein a corresponding gate electrode 1420 is formed, as shown in FIG. 14A. The gate electrode 1420 is formed of a metal such as aluminum (Al), molybdenum (Mo), chromium (Cr), titanium (Ta), copper (Cu), or an alloy.

A dielectric layer (gate insulating film) 1430 is formed on the first substrate 1410 and the plurality of gate electrodes 1420. In one embodiment, the gate insulating film 1430 is formed of hafnium oxide, tantalum nitride or hafnium oxynitride.

Then, an amorphous germanium layer 1442 formed on the gate insulating layer 1430 covers the gate electrode 1420 on each of the switching regions 1412, and then a doped amorphous germanium layer 1444 is formed on the amorphous germanium layer 1442. The doped amorphous germanium layer 1444 is formed on an n+ doped (n-type heavily doped) amorphous germanium or p+ doped (p-type heavily doped) amorphous germanium, and forms a contact layer, such as section 14B. Shown in the figure. In one embodiment, the amorphous germanium layer 1442 and the contact layer 1444 are formed by successively depositing amorphous germanium and doped amorphous germanium by PECVD and then patterning.

In addition, a gate insulating film 1430 of yttrium oxide or tantalum nitride, an amorphous germanium layer 1442 and a doped amorphous germanium layer 1444 are sequentially deposited, and then the amorphous germanium layer 1442 and the doped amorphous germanium layer 1444 are patterned. An amorphous germanium layer 1442 and a doped amorphous germanium layer 1444 are formed as shown in FIG. 14B.

Thereafter, a metal layer 1450 is formed on the gate insulating film 1430 and a contact layer 1444 is formed in the switching region 1412. A germanium-rich dielectric layer 1460 is then formed over each of the solar cell regions 1414 on the metal layer, as shown in Figure 14C.

As shown in FIG. 14D, masking, exposure, and etching processes are sequentially applied to metal layer 1450 to further define field effect transistors in each switching region 1412, wherein contact layer 1444 is divided into a source interface 1444a and a stack. The pole interface 1444b, and the metal layer 1450 is also divided into a first portion 1452 and a second portion 1454 within each zone 1412. The first portion 1452 is coupled to the source interface 1444a and a signal line, and the second portion 1454 is spaced apart from the first portion 1452 and to the drain interface 1444b as shown in FIG. 14D. In addition, a third portion 1456 of the metal layer 1450 spaced apart from the first portion 1452 and the second portion 1454 is formed in each solar cell region, as discussed below, as the first electrode of the solar cell.

As shown in FIG. 14E, a protective layer (film) 1470 covering all of the field effect transistors in each of the switching regions 1412 and covering the germanium-rich dielectric layer 1460 in each of the solar cell regions 1414 is then formed. Then, a protective layer 1470 is sequentially applied with a mask, an exposure, and an etching process to define a via 1472 for coupling the switching element to the pixel electrode (through the drain electrode 1454), and removing the germanium-rich dielectric layer 1460. cover. At this stage, a laser annealing treatment can be applied to the germanium-rich dielectric layer 1460 to form a plurality of laser-induced nanocrystals having multiple energy gaps.

As shown in FIG. 14F, the next step is to form a transparent metal layer having a first portion 1482 on the via 1472 and a separate second portion 1484 on the germanium-rich dielectric layer 1460. The first portion 1482 is coupled to the drain electrode 1454 of the field effect transistor and is referred to as a pixel electrode. The second portion 1484 of the transparent metal layer, the germanium-rich dielectric layer 1460, and the third portion 1456 of the metal layer 1450 form a solar cell. The transparent metal layer is formed of a transparent, electrically conductive material, and includes indium zinc oxide (IZO), amorphous indium oxide (ITO), poly-ITO, etc., and has a thickness in the range of about 0.01 to 3.0 μm.

Among these descriptions, the present invention discloses a germanium crystal, a multiple energy gap photocell, and applications thereof. The photovoltaic cell has a nanocrystal layer formed by post-annealing with a cerium-rich oxide layer. The nanocrystalline crystal cell (or photoreceptor) is a stable, advantageous, flexible, reliable and functional component for embedded LCD panels with large fill factor, complete backlight isolation and adjustable absorption spectrum. The advantages.

The above description of the exemplary embodiments of the present invention is intended to be illustrative and not restrictive Many modifications and changes can be made based on the above.

DETAILED DESCRIPTION OF THE INVENTION The present invention is best understood by the following description of the preferred embodiments of the invention Those skilled in the art will appreciate that other embodiments are also within the scope of the invention. Therefore, the scope of the invention is defined by the scope of the claims, rather than the foregoing description and the exemplary embodiments described herein.

100. . . Photocell

110. . . First conductive layer

140. . . Rich dielectric layer

145. . . Nano crystal

170. . . Second conductive layer

180. . . Dielectric layer

181. . . Contact hole

200. . . Photocell

210. . . First conductive layer

240. . . Rich dielectric layer

245. . . Nano crystal

270. . . Second conductive layer

292. . . Laser

295. . . Light

400. . . Photocell battery pack

401. . . Photocell

410. . . First conductive layer

440. . . Rich dielectric layer

445. . . Nano crystal

470. . . Second conductive layer

480. . . Rechargeable battery pack

485. . . Ammeter

495. . . Light

510-720. . . curve

900. . . Photocell

910. . . First conductive layer

920. . . First semiconductor layer

930. . . First rich dielectric layer

940. . . Second rich dielectric layer

960. . . Second semiconductor layer

970. . . Second conductive layer

1000. . . Photocell

1001. . . Photoelectric conversion layer

1010. . . First conductive layer

1020. . . N-type doped semiconductor layer

1030. . . First rich dielectric layer

1040. . . Second rich dielectric layer

1050. . . Third rich dielectric layer

1060. . . P-type doped semiconductor layer

1070. . . Second conductive layer

1101. . . Display panel

1102. . . LCD panel

1110. . . Display area

1120. . . Display area

1130. . . Light sensor

1140. . . Photocell

1150. . . Ambient light sensor

1160. . . LCD driver

1200. . . Low temperature polycrystalline germanium panel

1201. . . Photocell

1210. . . Substrate

1221. . . Display field effect transistor

1222. . . Source area

1224. . . Bungee area

1226. . . Gate electrode

1230. . . First conductive layer

1240. . . Rich dielectric layer

1245. . . Nano crystal

1270. . . Second conductive layer

1295. . . Ambient light

1296. . . Backlight

1300. . . Low temperature polycrystalline germanium panel

1301. . . Field effect transistor

1303. . . Storage capacitor

1305. . . Photoreceptor

1307. . . Active area

1310. . . Substrate

1355. . . First electrode

1365. . . Rich dielectric layer

1375. . . Second electrode

1400. . . method

1410. . . First substrate

1412. . . Switching area

1414. . . Solar cell area

1420. . . Gate electrode

1430. . . Dielectric layer

1442. . . Amorphous layer

1444. . . Doped amorphous germanium layer

1444a. . . Source interface

1444b. . . Bungee interface

1450. . . Metal layer

1452. . . first part

1454. . . the second part

1456. . . the third part

1460. . . Rich dielectric layer

1470. . . The protective layer

1472. . . Through hole

1482. . . first part

1484. . . the second part

BRIEF DESCRIPTION OF THE DRAWINGS One or more embodiments of the present invention can be used to explain the principles of the invention. Wherever they are used, the same reference numbers will be used in all drawings to represent the same or similar parts, in which:

1 is a cross-sectional view showing a photovoltaic cell in accordance with an embodiment of the present invention;

2 is a diagram showing the fabrication of a photovoltaic cell having a germanium-rich dielectric layer having a plurality of laser-induced nanocrystals in accordance with an embodiment of the present invention: (A) in a Forming a germanium-rich dielectric layer on a conductive layer; (B) laser annealing the germanium-rich dielectric layer to form a plurality of germanium crystals; and (C) forming a second conductive layer on the germanium-rich dielectric layer Floor;

Figure 3 shows the characteristics of the laser-induced nanocrystals: (A) a TEM image showing the size of the nanocrystals, and (B) the nanocrystals in the laser-induced nanocrystals Distribution of size;

4 is a cross-sectional view showing a photovoltaic cell in accordance with an embodiment of the present invention;

Figure 5 shows the photocurrent response of the photocell to an incident white light;

Figure 6 shows an ytterbium-rich yttrium oxide layer formed using different laser annealing power intensities, which photochromic reaction to an incident white light;

Figure 7 is a diagram showing current-voltage characteristics of a photovoltaic cell in accordance with an embodiment of the present invention;

Figure 8 is a diagram showing the spectral characteristics of a photovoltaic cell having a multiple energy gap in accordance with an embodiment of the present invention, wherein the multiple energy gap is divided into a plurality of narrow regions;

Figure 9 is a cross-sectional view showing a photovoltaic cell in accordance with an embodiment of the present invention;

Figure 10 is a cross-sectional view showing a photovoltaic cell according to other embodiments of the present invention;

11A and 11B are diagrams showing a display panel incorporating one or more nanocrystalline crystal cells in accordance with an embodiment of the present invention;

12 is a cross-sectional view showing a low temperature polycrystalline germanium panel incorporating a plurality of nanocrystalline crystal cells in accordance with an embodiment of the present invention;

Figure 13 is a cross-sectional view showing a low temperature polycrystalline germanium panel incorporating a plurality of nanocrystalline crystal cells in accordance with other embodiments of the present invention;

14A through 14F are diagrams showing the process for fabricating a low temperature polycrystalline germanium panel incorporating a plurality of nanocrystalline crystal cells in accordance with an embodiment of the present invention.

100. . . Photocell

110. . . First conductive layer

140. . . Rich dielectric layer

145. . . Nano crystal

170. . . Second conductive layer

180. . . Dielectric layer

181. . . Contact hole

Claims (39)

A photovoltaic cell comprising: (a) a first conductive layer; (b) an N-type doped semiconductor layer formed on the first conductive layer; (c) a first germanium layer formed on the N-type doped semiconductor layer (d) a first silicon-rich (Si-rich) dielectric layer formed on the first germanium layer and having a refractive index n1; (e) a second germanium-rich (Si-rich) dielectric layer Forming on the first ytterbium-rich dielectric layer and having a refractive index n2, wherein n2<n1; (f) a second ruthenium layer is formed on the second ytterbium-rich dielectric layer; (g) a P-type A doped semiconductor layer is formed on the second germanium layer; and (h) a second conductive layer is formed on the p-type doped semiconductor layer. The photovoltaic cell of claim 1, wherein one of the first layer and the second layer is made of amorphous germanium (a-Si), and the first layer and the second layer The other of the tantalum layers is made of poly-Si. The photovoltaic cell of claim 1, wherein at least one of the first ruthenium-rich dielectric layer and the second ruthenium-rich dielectric layer comprises a nanocrystalline germanium (nc-Si) layer, The nanocrystalline ruthenium layer comprises a plurality of ruthenium crystals, each of which has a size between about 1 nm and 20 nm. The photovoltaic cell of claim 1, wherein at least one of the first conductive layer and the second conductive layer is made of a transparent conductive material. The photovoltaic cell according to claim 4, wherein the transparent conductive material is indium tin oxide (ITO), indium zinc oxide (IZO), aluminum zinc oxide (AZO), hafnium oxide (HfO) or the like. The combination. The photovoltaic cell of claim 1, wherein the material of the N-type doped semiconductor layer is an N-type doped germanium, and wherein the material of the P-type doped semiconductor layer is a P-type doped germanium. A method of manufacturing a photovoltaic cell, comprising the steps of: (a) providing a substrate; (b) forming a first conductive layer on the substrate; (c) forming an N-type doped semiconductor layer on the first conductive layer; (d) forming a first germanium layer on the N-type doped semiconductor layer; (e) forming a first germanium-rich (Si-rich) dielectric layer on the first germanium layer, wherein the first germanium layer The dielectric layer has a refractive index n1; (f) forming a second germanium-rich (Si-rich) dielectric layer on the first germanium-rich dielectric layer, wherein the second germanium-rich dielectric layer has a refraction a rate n2, and n2 < n1; (g) forming a second germanium layer on the second germanium-rich dielectric layer; (h) forming a p-type doped semiconductor layer on the second germanium layer; and (i Forming a second conductive layer on the P-type doped semiconductor layer. The method of claim 7, further comprising: laser annealing at least one of the first ruthenium-rich dielectric layer and the second ruthenium-rich dielectric layer to form a plurality of ruthenium crystals . A photovoltaic cell comprising: (a) a first conductive layer; (b) a second conductive layer; and (c) a photoelectric conversion layer formed between the first conductive layer and the second conductive layer, wherein the photoelectric conversion layer has a a multiple energy gap, the photoelectric conversion layer comprising: (i) a first silicon-rich (Si-rich) dielectric layer formed on the first conductive layer and having a refractive index n1; and (ii) a second A Si-rich dielectric layer is formed on the first ytterbium-rich dielectric layer and has a refractive index n2, where n2 < n1. The photovoltaic cell of claim 9, wherein the photoelectric conversion layer further comprises: (i) an amorphous germanium (a-Si) layer; and (ii) a poly-Si layer, wherein the A germanium rich dielectric layer and the second germanium rich dielectric layer are formed between the amorphous germanium layer and the poly germanium layer. The photovoltaic cell of claim 10, wherein the material of the first ruthenium-rich dielectric layer and the second ruthenium-rich dielectric layer comprises a ruthenium-rich oxide, a ruthenium-rich nitride, and a ruthenium-rich ruthenium oxide. a substance, a ruthenium-rich carbide or a combination of these. The photovoltaic cell of claim 10, wherein at least one of the first germanium-rich dielectric layer and the second germanium-rich dielectric layer comprises a nanocrystalline germanium (nc-Si) layer, The nanocrystalline crystalline layer has a plurality of nanocrystals, each of which has a size between about 1 nanometer and about 20 nanometers. The photovoltaic cell of claim 9, wherein the photoelectric conversion layer further comprises a third germanium-rich dielectric layer formed between the second germanium-rich dielectric layer and the second conductive layer, the third rich The germanium dielectric layer has a refractive index n3, where n3 < n2 < n1. The photovoltaic cell of claim 13, wherein the material of each of the first ruthenium-rich dielectric layer, the second ruthenium-rich dielectric layer, and the third ruthenium-rich dielectric layer comprises a ruthenium-rich oxide and a rich Niobium nitride, a niobium-rich niobium oxide, a niobium-rich carbide or a combination of these. The photovoltaic cell of claim 9, further comprising: (i) an N-type doped semiconductor layer formed between the first conductive layer and the photoelectric conversion layer; and (ii) a P-type doped semiconductor A layer is formed between the second conductive layer and the photoelectric conversion layer. The photovoltaic cell of claim 9, wherein at least one of the first and second conductive layers is made of a transparent conductive material. A method of manufacturing a photovoltaic cell comprising the steps of: (a) providing a substrate; (b) forming a first conductive layer on the substrate; (c) forming a photoelectric conversion layer on the first conductive layer, wherein the photovoltaic The conversion layer has a multi-band gap and comprises: (i) forming a first silicon-rich (Si-rich) dielectric layer on the first conductive layer The first ytterbium layer has a refractive index n1; and (ii) forms a second ytterbium (Si-rich) dielectric layer on the first ytterbium layer, wherein the second ytterbium layer has a refractive index n2, and n2 < n1; and (d) forming a second conductive layer on the photoelectric conversion layer. The method of claim 17, wherein the step of forming the photoelectric conversion layer further comprises the steps of: (i) forming a first germanium layer on the first conductive layer; and (ii) forming a second germanium layer. On the second germanium-rich dielectric layer, wherein one of the first germanium layer and the second germanium layer comprises an amorphous germanium (a-Si) layer, and the first germanium layer and the second germanium layer The other of the layers contains a poly-Si layer. The method of claim 17, wherein the step of forming the first ruthenium rich layer and the second ruthenium rich layer further comprises: laser annealing the first ruthenium rich layer and the second ruthenium rich layer to form A plurality of nano crystals. The method of claim 17, wherein the step of forming the photoelectric conversion layer further comprises: forming a third germanium-rich dielectric layer between the second germanium-rich dielectric layer and the second conductive layer, The third germanium-rich dielectric layer has a refractive index n3, where n3 < n2 < n1. If the method described in claim 17 is applied, the method further includes And comprising: (i) forming an N-type doped semiconductor layer between the first conductive layer and the photoelectric conversion layer; and (ii) forming a P-type doped semiconductor layer on the second conductive layer and the photoelectric conversion layer between. A liquid crystal display panel is driven by a liquid crystal display driver and illuminated by a backlight, the liquid crystal display panel comprising: (a) a display area for displaying related information; and (b) a photocell, the photocell The optical energy of the light is converted into an electric energy in an area surrounding the display area and exposed to a light, and the electric energy is supplied to the liquid crystal display driver as a driving power, wherein the photo battery comprises: (i) a first a conductive layer; (ii) a second conductive layer; and (iii) a photoelectric conversion layer formed between the first conductive layer and the second conductive layer, wherein the photoelectric conversion layer has a multiple energy gap. The liquid crystal display panel of claim 22, wherein the photoelectric conversion layer further comprises: (i) an amorphous germanium (a-Si) layer; (ii) a poly-Si layer; Iii) A Si-rich dielectric layer is formed between the amorphous germanium layer and the polysilicon layer. The liquid crystal display panel of claim 23, wherein the rich The material of the germanium dielectric layer comprises a cerium-rich oxide, a germanium-rich nitride, a germanium-rich oxynitride, a germanium-rich carbide or a combination of these. The liquid crystal display panel of claim 24, wherein the ytterbium-rich dielectric layer comprises a nanocrystalline 矽 (nc-Si) layer, the nanocrystalline 矽 layer having a plurality of 矽 nanocrystals, each The size of the nanocrystals is between about 1 nanometer and about 20 nanometers. The liquid crystal display panel of claim 22, wherein the photoelectric conversion layer comprises: (i) a first silicon-rich (Si-rich) dielectric layer formed on the first conductive layer and having a refraction And a (ii) a second Si-rich dielectric layer formed on the first ytterbium-rich dielectric layer and having a refractive index n2, wherein n2 < n1. The liquid crystal display panel of claim 26, wherein the photoelectric conversion layer further comprises a third germanium-rich dielectric layer formed between the second germanium-rich dielectric layer and the second conductive layer, the first The tri-rich dielectric layer has a refractive index n3, where n3 < n2 < n1. The liquid crystal display panel of claim 22, wherein the display region has a plurality of low temperature polycrystalline silicon thin film transistors (LTPS-TFTs). A method for manufacturing a liquid crystal display (LCD) panel, the liquid crystal display The display panel is driven by a liquid crystal display driver and illuminated by a backlight, the method comprising: (a) providing a substrate; (b) forming a display area on the substrate; and (c) forming a photocell around The substrate in an area of the display area is exposed to light. When the photocell converts light energy into an electric energy, the electric energy is supplied to the liquid crystal display driver as a driving power, and the step of forming the photocell includes the steps of: (i) forming a first conductive layer; (ii) forming a second conductive layer; and (iii) forming a photoelectric conversion layer between the first conductive layer and the second conductive layer, wherein the photoelectric conversion layer has A multiple energy gap. The method of claim 29, wherein the step of forming the photoelectric conversion layer comprises: (i) forming a first germanium layer on the first conductive layer; (ii) forming a germanium rich (Si-rich) a dielectric layer on the first germanium layer; and (iii) forming a second germanium layer on the germanium-rich dielectric layer that completes the laser annealing, wherein the first germanium layer and the second germanium layer are One comprises an amorphous germanium (a-Si) layer, and the other of the first germanium layer and the second germanium layer comprises a poly-Si layer. The method of claim 30, wherein the step of forming the germanium-rich dielectric layer further comprises: laser annealing the germanium-rich dielectric layer to form a plurality of germanium crystals. The method of claim 29, wherein the step of forming the photoelectric conversion layer comprises: (i) forming a first silicon-rich (Si-rich) dielectric layer on the first conductive layer, the first The ruthenium-rich dielectric layer has a refractive index n1; and (ii) a second Si-rich dielectric layer is formed on the first ytterbium-rich dielectric layer, the second ytterbium-rich dielectric layer has a The refractive index n2, where n2 < n1. The method of claim 32, wherein the step of forming the photoelectric conversion layer further comprises: forming a third germanium-rich dielectric layer between the second germanium-rich dielectric layer and the second conductive layer, The third germanium-rich dielectric layer has a refractive index n3, where n3 < n2 < n1. A display panel comprising: a plurality of pixels arranged in a matrix form, each pixel comprising: (a) an active area for displaying related information; (b) a switching area having at least one switching element; and (c) a A photocell is formed between the active region and the switching region, wherein the photovoltaic cell has a photoelectric conversion layer, and the photoelectric conversion layer includes a multiple energy gap. The display panel of claim 34, wherein the photoelectric conversion layer comprises: (i) an amorphous germanium (a-Si) layer; (ii) a poly-Si layer; (iii) A Si-rich dielectric layer is formed between the amorphous germanium layer and the polysilicon layer. The display panel of claim 35, wherein the ytterbium-rich dielectric layer comprises a nanocrystalline germanium (nc-Si) layer, the nanocrystalline germanium layer having a plurality of nanocrystals, each of which The nanocrystal size ranges from about 1 nanometer to about 20 nanometers. A method of manufacturing a display panel, comprising: (a) providing a substrate; and (b) forming a plurality of pixels in a matrix on the substrate, wherein each pixel comprises a photovoltaic cell, wherein the photovoltaic cell has a photoelectric conversion layer, The photoelectric conversion layer includes a multiple energy gap. The method of claim 37, wherein the forming the pixels comprises: (i) forming a plurality of gates electrically coupled to the plurality of gate lines on the substrate, wherein the gates are spatially each other Separating, and each pair of adjacent ones of the gates defines an active area, a switching area, and a photocell in which the gate is formed, the photocell being located between the active area and the switching area; (ii) Forming a gate insulating layer on the gates and the remaining regions of the substrate; (iii) forming an amorphous germanium (a-Si) layer over the gate insulating layer covering the gates in each switching region (iv) forming a doped amorphous germanium layer on the amorphous germanium layer; (v) forming a first conductive layer on the doped amorphous germanium layer and the remaining region of the gate insulating layer; (vi) forming a germanium-rich (Si) covering each photocell region on the first conductive layer a -rich) dielectric layer; (vii) forming a source and a drain in each switching region, thereby forming a field-effect transistor array on the substrate; (viii) forming a passive layer at the first conductive Overlaying the field effect transistor array and the germanium rich dielectric layer; (ix) forming a via contact on the passive region in the switching region and the photocell region; and (x) in the switching region and the photocell region Forming a second conductive layer having a first portion therebetween, such that the first portion contacts the drain of the field effect transistor through the via hole in each switching region, and contacts the photocell region A second part of the rich dielectric layer. The method of claim 38, wherein the step of forming the plurality of pixels further comprises laser annealing the germanium-rich dielectric layer to form a plurality of germanium crystals therein.