JP2005203596A - Production method of electro-optical device, electro-optical device and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electro-optical device in which lattice defect, or the like, of a semiconductor layer 220 can be repaired while enhancing adhesion of the semiconductor layer 220 and a supporting substrate 500. <P>SOLUTION: The production method of an electro-optical device comprises a step for sticking a semiconductor substrate to the surface of a supporting substrate 500, step (A) for forming a semiconductor layer 220 by separating the semiconductor substrate in a hydrogen ion implantation layer, and step (B) for melting the surface layer part of the semiconductor layer 220 by irradiating it with a laser beam having an absorption wavelength of the semiconductor layer 220. Recrystallization can be carried out using regular crystal lattice at a lower layer part as nucleus by melting the surface layer part of the semiconductor layer 220. Furthermore, since heat generated by laser irradiation is transmitted to the sticking interface of the semiconductor layer 220 and the supporting substrate 500, adhesion of the sticking interface can be enhanced. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for manufacturing an electro-optical device, an electro-optical device, and an electronic apparatus.

  SOI (Silicon On Insulator) technology, which uses a silicon layer provided on an insulator layer to form a semiconductor device, is not suitable for ordinary single crystal silicon substrates such as α-ray resistance, latch-up characteristics, or short channel suppression effects. In order to show excellent characteristics that cannot be achieved, the development of semiconductor devices has been promoted for the purpose of high integration of semiconductor devices.

  As a method for forming such an SOI structure (a structure in which a silicon layer is formed on an insulator layer), for example, there is a method by bonding a single crystal silicon substrate. This method, commonly referred to as a bonding method, is a method in which a single crystal silicon substrate as a silicon layer and a support substrate as an insulator layer are overlapped with an oxide film and bonded at room temperature using OH groups on the substrate surface. After that, the single crystal silicon substrate is thinned by grinding, polishing, etching, or the like, and subsequently the siloxane bond (Si—O—Si) is increased by heat treatment at about 600 ° C. to 1200 ° C. A silicon layer is formed on a support substrate. According to this method, since the single crystal silicon substrate is directly thinned, the silicon thin film has excellent crystallinity, and thus a high-performance device can be manufactured.

  In Patent Document 1, a single crystal silicon substrate and a light-transmitting insulating substrate are overlapped, and a laser is irradiated from the light-transmitting substrate side to improve the adhesion between them, and then the surface of the single crystal silicon substrate A technique for thinning the film by polishing or etching is disclosed. However, when the single crystal silicon substrate is made ultrathin by polishing, etching, or the like, it is difficult to obtain good in-plane uniformity.

Accordingly, a technique for implanting hydrogen ions into a single crystal silicon substrate and bonding it to a supporting substrate, and then performing a first heat treatment to weaken the hydrogen implanted region and separate the thin film silicon layer from the single crystal silicon substrate. Has been developed. Further, by performing the second heat treatment on the bonding interface between the single crystal silicon substrate and the support substrate, the adhesion at the bonding interface is improved.
JP-A-6-20895

  However, when the SOI structure composite semiconductor substrate is used in an electro-optical device such as a transmissive liquid crystal device, a light transmissive substrate such as a quartz substrate is used as a support substrate. The coefficient of thermal expansion of these will differ. In this case, when heat treatment is performed at a high temperature, a large thermal stress acts on the single crystal silicon layer, and slips, dislocations, lattice defects, HF defects, and the like are generated, which may hinder device characteristics. Further, the single crystal silicon layer is warped, cracked, etc., leading to destruction, and the device yield is reduced.

  The present invention has been made in order to solve the above-described problems, and is capable of repairing lattice defects and the like formed in a semiconductor layer and preventing breakdown of the semiconductor layer. An object is to provide a method for manufacturing an optical device. It is another object of the present invention to provide a low-cost electro-optical device and electronic equipment with excellent display quality.

In order to solve the above problems, a method of manufacturing an electro-optical device according to the present invention includes a step of bonding a semiconductor substrate to a surface of a support substrate, and forming the semiconductor layer on the surface of the support substrate by thinning the semiconductor substrate And a step of melting a surface layer portion of the semiconductor layer by irradiating the semiconductor layer with a laser having an absorption wavelength by the semiconductor layer.
The lower layer portion of the semiconductor layer is composed of a regular crystal lattice without lattice defects. Therefore, by melting the surface layer portion of the semiconductor layer, it is possible to regularly recrystallize the crystal lattice of the lower layer portion as a nucleus. This makes it possible to repair lattice defects formed in the semiconductor layer. On the other hand, heat generated by laser irradiation is transmitted to the bonding interface between the semiconductor layer and the support substrate, so that the adhesion at the bonding interface can be improved. Therefore, it can also serve as the second heat treatment for improving the adhesion at the bonding interface.

The support substrate and the semiconductor layer may be made of materials having different thermal expansion coefficients.
When the thermal expansion coefficients of the supporting substrate and the semiconductor layer are different, lattice defects or the like may be formed in the semiconductor layer by the heat treatment. However, according to the configuration of the present invention, lattice defects and the like formed in the semiconductor layer can be repaired. Further, when the support substrate and the semiconductor layer are made of materials having different thermal expansion coefficients, the semiconductor layer may be destroyed by a high-temperature heat treatment. However, if the semiconductor substrate is heated by laser irradiation, only the laser irradiation region is partially heated, so that a large thermal stress does not act on the semiconductor substrate. Accordingly, it is possible to prevent the semiconductor layer from being destroyed by the heat treatment.

Further, it is preferable that the laser irradiation on the semiconductor layer is performed so as to scan the semiconductor layer.
According to this configuration, since the entire surface of the semiconductor layer can be sequentially heated, lattice defects and the like can be repaired over the entire surface of the semiconductor layer while preventing the semiconductor layer from being destroyed.

In addition, it is preferable that the laser irradiation on the semiconductor layer is performed only on a semiconductor element formation region in the semiconductor layer.
According to this configuration, the energy consumption accompanying laser irradiation is reduced, and the heat treatment time is shortened, so that the manufacturing cost can be reduced.

The thinning of the semiconductor substrate may be performed by separating the semiconductor substrate in a hydrogen ion implantation layer of the semiconductor substrate.
In the step of separating the semiconductor substrate in the hydrogen ion implanted layer, lattice defects may be formed in the semiconductor layer by heat treatment, and the semiconductor layer may be destroyed. However, according to the configuration of the present invention, it is possible to repair lattice defects and the like of the semiconductor layer. Further, it becomes possible to prevent the semiconductor layer from being destroyed.

In addition, it is desirable that the laser irradiation on the semiconductor layer be performed while focusing on the surface of the semiconductor layer.
According to this configuration, the semiconductor layer can be dissolved from the surface layer portion to the middle layer portion without dissolving the lower layer portion of the semiconductor layer. As a result, the entire semiconductor layer can be regularly recrystallized, and lattice defects and the like of the semiconductor layer can be reliably repaired.

The laser may be an excimer laser. The laser may be a continuous wave argon laser.
An excimer laser or a continuous wave argon laser can irradiate a laser beam having an absorption wavelength of a semiconductor layer and a transmission wavelength of a supporting substrate. Thereby, only a semiconductor layer can be heated, without damaging a support substrate.

On the other hand, an electro-optical device according to the present invention is manufactured using the above-described electro-optical device manufacturing method.
By using the above-described method for manufacturing an electro-optical device, it becomes possible to repair a lattice defect or the like of the semiconductor layer, so that an electro-optical device with excellent display quality can be provided. In addition, the semiconductor layer can be prevented from being broken and the yield is improved, so that a low-cost electro-optical device can be provided.

On the other hand, an electronic apparatus according to the present invention includes the above-described electro-optical device.
According to this configuration, it is possible to provide a low-cost electronic device with excellent display quality.

Embodiments of the present invention will be described below with reference to the drawings.
[First embodiment]
1 and 2 are process cross-sectional views illustrating a method for manufacturing a composite semiconductor substrate (bonded substrate) having an SOI structure according to the first embodiment of the present invention. In addition, in each figure, in order to make each layer and each member into a size that can be recognized on the drawing, the scale is appropriately changed for each layer and each member.

  In this embodiment, first, as shown in FIG. 1A, a single crystal silicon substrate (semiconductor substrate) 200 having a thickness of, for example, 750 μm is prepared, and the first surface 201 and the second surface 202 are mirror-polished. Process. Thereafter, the first surface 201 and the second surface 202 of the single crystal silicon substrate 200 are thermally oxidized to form silicon oxide films (insulating layers) 210 and 211. The thicknesses of the silicon oxide films 210 and 211 may be equal to or greater than the thickness at which the bonding surface becomes hydrophilic in a bonding process described later. In this example, the silicon oxide films 210 and 211 are formed to have a thickness of about 200 nm.

Next, as shown in FIG. 1B, hydrogen ions are implanted into the single crystal silicon substrate 200 through the silicon oxide film 210. As a result, a hydrogen ion implantation layer 205 having a penetration depth distribution as shown by a broken line in FIG. 1B is formed inside the single crystal silicon substrate 200. As hydrogen ion implantation conditions at this time, for example, acceleration energy is set to 60 to 150 keV, and dose is set to 5 × 10 ¹⁶ atoms / cm ² to 15 × 10 ¹⁶ atoms / cm ² . Note that a composite semiconductor substrate having single crystal silicon layers having different thicknesses can be obtained by changing the acceleration voltage of hydrogen ions to change the implantation depth of hydrogen ions.

Next, as shown in FIG. 1C, a supporting substrate 500 on which the single crystal silicon substrate 200 is bonded is prepared. When a substrate made of a light transmissive material such as glass or quartz (light transmissive substrate) is adopted as the support substrate 500, the obtained composite semiconductor substrate is used as a transmissive electro-optical device, for example, a transmissive type substrate. It can be applied to liquid crystal devices (light bulbs). Subsequently, an oxide film (insulating layer) 510 such as a silicon oxide film or NSG (non-doped silicate glass) is formed on the entire surface of the support substrate 500 by sputtering or CVD. Next, the surface 501 of the oxide film 510 is planarized by polishing using a CMP method or the like. Here, the thickness of the oxide film 510 is, for example, about 400 to 1000 nm, more preferably about 800 nm. In the case of using a substrate composed mainly of Si0 ₂ such as quartz as a support substrate 500 may be omitted this formation of the oxide film 510 steps.

  Next, as shown in FIG. 1D, the surface of the single crystal silicon substrate 200 on the oxide film 210 side and the surface of the support substrate 500 on the silicon oxide film 210 side are joined together, and the oxide films 210 and 510 are interposed therebetween. Then, the single crystal silicon substrate 200 is bonded onto the supporting substrate 500 at room temperature to 200 ° C. Here, the oxide films (insulating layers) 210 and 510 are formed to ensure adhesion between the single crystal silicon substrate (semiconductor substrate) 200 and the support substrate 500. That is, due to the action of OH groups on the substrate surface, the single crystal silicon substrate 200 and the support substrate 500 are bonded to each other through the insulating layer 550 (oxide films 210 and 510) as shown in FIG. A semiconductor substrate (bonded substrate) 600 is formed.

  Note that a film (not illustrated) of molybdenum, tungsten, or the like may be formed between the supporting substrate 500 and the insulating layer 550. Since such a film functions as a heat conductive film, the temperature distribution of the support substrate 500 can be improved. Therefore, in the step of bonding the supporting substrate 500 and the single crystal silicon substrate 200, it is possible to make the temperature distribution at the bonding interface uniform by this thermal conductive film, and the adhesion at the bonding interface is made uniform. As a result, the bonding strength can be improved. Further, when used in a transmissive liquid crystal device or the like, a film of molybdenum, tungsten, or the like can function as a light-blocking layer. In addition to the materials listed above, materials that can be used for such a film include refractory metals such as tantalum, cobalt, titanium, alloys containing them, polycrystalline silicon, tungsten silicide, and molybdenum. Examples thereof include a silicide film typified by silicide.

  Next, as shown in FIG. 2A, the single crystal silicon substrate 200 in the composite semiconductor substrate 600 after bonding is thinned to, for example, about 200 nm to form a single crystal silicon layer 220. This single crystal silicon layer 220 is obtained by separating and cutting the single crystal silicon substrate at the position of the hydrogen ion implantation layer 205 by heat-treating the semiconductor substrate 200 shown in FIG. 1E at a low temperature of 400 ° C. to 700 ° C., for example. Formed by. This separation and cutting phenomenon is caused by the bond of single crystal silicon being broken by hydrogen ions introduced into the single crystal silicon substrate 200, and is more prominent at the peak position of the ion concentration in the hydrogen ion implanted layer. It becomes. Therefore, the position where the separation and cutting are performed by the heat treatment substantially matches the peak position of the ion concentration.

  Note that, as shown in FIG. 2A, the surface of the single crystal silicon layer 220 exposed by the above-described separation and cutting has unevenness of about several nanometers, so that the surface is smoothed by CMP or in a hydrogen atmosphere. The surface is preferably smoothed by a hydrogen annealing method in which heat treatment is performed. In addition, the single crystal silicon substrate thus separated can be used for manufacturing another SOI substrate as it is.

By the way, heat treatment is performed on the single crystal silicon substrate in the process of manufacturing the single crystal silicon substrate and in the above-described separation process of the single crystal silicon substrate. This heat treatment may cause slips, dislocations, lattice defects, HF defects and the like in the single crystal silicon layer, which may impair device characteristics.
Therefore, as shown in FIG. 2B, the single crystal silicon layer 220 is irradiated with a laser 630 and its surface layer portion is melted to repair lattice defects or the like generated in the single crystal silicon layer 220.

  As the laser, a laser capable of irradiating light having an absorption wavelength by the single crystal silicon layer 220 is employed. Specifically, excimer lasers such as ArF (wavelength 193 nm), KrF (wavelength 249 nm), XeCl (wavelength 308 nm), and XeF (wavelength 350 nm) are employed. A CW (continuous wave) Ar laser (wavelength 488 nm, 515 nm) can also be employed.

  By irradiating the single crystal silicon layer 220 with such a laser, the single crystal silicon layer absorbs the laser light and generates heat. At that time, the energy density and irradiation time of the laser are controlled so that the temperature of the single crystal silicon layer 220 is 1414 ° C. or higher which is the melting temperature of silicon. Thereby, the single crystal silicon in the laser irradiation region can be melted. Note that the lower layer portion of the single crystal silicon layer 220, that is, the vicinity of the bonding interface with the support substrate 500 in the single crystal silicon layer 220 is formed of a regular crystal lattice having no lattice defects. Therefore, the melted single crystal silicon can be regularly recrystallized in the cooling process using this crystal lattice as a nucleus. This makes it possible to repair slits, dislocations, lattice defects, HF defects and the like formed in the single crystal silicon layer.

  Note that the focal point of the laser light is preferably matched with the surface of the single crystal silicon layer 220. As a result, melting can proceed from the surface layer portion to the middle layer portion of the single crystal silicon layer 220. Further, by controlling the laser energy density and the irradiation time, it is possible to melt all but the lower layer portion of the single crystal silicon layer 220. Thus, the entire single crystal silicon layer 220 can be regularly recrystallized, and lattice defects and the like formed in the single crystal silicon layer can be reliably repaired.

  Further, heat generated by laser irradiation and diffused to the single crystal silicon substrate 200 is transferred to the bonding interface between the single crystal silicon layer 220 and the support substrate 500. In general, the thermal conductivity of the single crystal silicon layer 220 is higher than the thermal conductivity of the support substrate 500 made of a light-transmitting material, so that the heat generated in the single crystal silicon layer 220 is quickly transferred to the bonding interface. . Then, the heat transferred to the bonding interface volatilizes hydrogen (H) existing at the interface and generates Si—O—Si bonds. Thereby, the adhesiveness of the bonding interface is improved. In this manner, by irradiating the single crystal silicon layer 220 with a laser, it is possible to simultaneously repair lattice defects of the single crystal silicon layer and improve the bonding strength. Thereby, it is not necessary to separately perform heat treatment for improving the bonding strength, and manufacturing efficiency is not reduced.

  In addition, it is known that adhesiveness will improve, so that the temperature of a bonding interface is high, especially when the temperature of a bonding interface exceeds 1100 degreeC. As described above, when the laser irradiation region is heated to around 1414 ° C., the temperature of the bonding interface can be set to 1100 ° C. or higher by heat transfer. In this case, sufficient adhesion at the bonding interface can be ensured.

  Note that since laser light has high directivity, it is difficult to irradiate the entire surface of the single crystal silicon layer 220 at the same time. Therefore, the laser is irradiated so as to scan the single crystal silicon layer 220 by moving the composite semiconductor substrate or the laser. As a result, the entire surface of the single crystal silicon layer 220 can be irradiated with laser. In this case, in the single crystal silicon layer 220, only the laser irradiation region generates heat, and the heat is diffused into the single crystal silicon layer 220, and the region is cooled. In this way, partial heating and cooling are sequentially performed in the single crystal silicon layer 220. Therefore, even when the thermal expansion coefficients of the single crystal silicon layer 220 and the support substrate 500 are different, a large thermal stress is not applied by the heat treatment, and the single crystal silicon layer can be prevented from being broken due to warpage or cracking. .

  However, it is sufficient that the laser irradiation is performed only on the semiconductor element formation region 225 in the single crystal silicon layer 220. As will be described later, in the composite semiconductor substrate used in the electro-optical device, the single crystal silicon layer 220 formed on the surface of the support substrate 500 is patterned to form a semiconductor element such as a thin film transistor. Therefore, it is sufficient to repair lattice defects in the single crystal silicon layer 220 and secure the bonding strength of the formation region 225 of the semiconductor element. In this manner, by performing laser irradiation only on the semiconductor element formation region 225, energy consumption due to laser irradiation is reduced, and heat treatment time is shortened, so that manufacturing costs can be reduced.

  Subsequently, as shown in FIG. 2C, a resist layer is formed on the single crystal silicon layer 220, and a resist pattern 620 covering the semiconductor element formation region 225 is formed by performing exposure and development processing. To do. Here, the semiconductor element formation region 225 is a region in the single crystal silicon layer 220 where an active element, for example, a switching element, a logic circuit, a micro electro mechanical systems (MEMS) element, or the like is formed.

Using the resist pattern 620 as a mask, regions other than the semiconductor element formation region 225 in the single crystal silicon layer 220 are removed by etching as shown in FIG. Regarding the etching of the single crystal silicon layer 220, it is preferable to employ wet etching so that the single crystal silicon pattern 220B to be formed is not damaged. Then, by removing the resist pattern, a single crystal silicon pattern 220B is formed in the semiconductor element formation region 225.
Thus, the composite semiconductor substrate 600 of the first embodiment is formed.

[Second Embodiment]
The method described in the first embodiment can be applied to the manufacture of various electro-optical devices. Therefore, in this embodiment, an example in which an active matrix substrate (semiconductor device) of a liquid crystal device (electro-optical device) is configured using the composite semiconductor substrate (bonded substrate) 600 formed in the first embodiment will be described.

(Overall configuration of liquid crystal device)
3 is a plan view of the liquid crystal device as viewed from the counter substrate side, and FIG. 4 is a cross-sectional view taken along line HH ′ of FIG. 3 including the counter substrate.
In FIG. 3, a sealing material 52 is provided along the edge on the active matrix substrate 10 of the liquid crystal device 100, and a frame 53 made of a light-shielding material is formed in the inner region. A data line driving circuit 101 and an external input terminal 102 are provided along one side of the active matrix substrate 10 in a region outside the sealing material 52, and the scanning line driving circuit 104 is provided on two sides adjacent to the one side. Are formed along.

  Needless to say, if the delay of the scanning signal supplied to the scanning line is not a problem, the scanning line driving circuit 104 may be provided on only one side. The data line driving circuit 101 may be arranged on both sides along the side of the image display area 10a. For example, the odd-numbered data lines supply an image signal from a data line driving circuit disposed along one side of the image display area 10a, and the even-numbered data lines are on the opposite side of the image display area 10a. An image signal may be supplied from a data line driving circuit arranged along the line. If the data lines are driven in a comb-like shape in this way, the formation area of the data line driving circuit 101 can be expanded, so that a complicated circuit can be configured. Further, the remaining side of the active matrix substrate 10 is provided with a plurality of wirings 105 for connecting between the scanning line driving circuits 104 provided on both sides of the image display region 10a. In some cases, a precharge circuit or an inspection circuit is provided. Further, at least one corner of the counter substrate 20 is formed with a vertical conductive material 106 for electrical conduction between the active matrix substrate 10 and the counter substrate 20.

  As shown in FIG. 4, the counter substrate 20 having substantially the same outline as the sealing material 52 is fixed to the active matrix substrate 10 by the sealing material 52. The sealing material 52 is an adhesive made of a photocurable resin or a thermosetting resin for bonding the active matrix substrate 10 and the counter substrate 20 around them, and the distance between the two substrates is set to a predetermined value. Therefore, gap materials such as glass fiber and glass beads are blended.

  As will be described in detail later, pixel electrodes 9 a are formed in a matrix on the active matrix substrate 10. On the other hand, a light shielding film 23 called a black matrix or a black stripe is formed on the counter substrate 20 in a region facing a peripheral region of a pixel electrode (described later) formed on the active matrix substrate 10. On the upper layer side, a counter electrode made of an ITO film is formed.

  The liquid crystal device thus formed is used, for example, in a projection type liquid crystal display device (liquid crystal projector) described later. In this case, the three liquid crystal devices 100 are respectively used as RGB light valves, and each liquid crystal device 100 receives light of each color as a projection light through a dichroic mirror for RGB color separation. It will be incident. Therefore, no color filter is formed in the liquid crystal device 100 of the present embodiment.

  However, by forming an RGB color filter together with its protective film in a region facing each pixel electrode 9a in the counter substrate 20, in addition to the projection type liquid crystal display device, a mobile computer, a cellular phone, a liquid crystal television, etc., which will be described later, etc. It can be used as a color liquid crystal display device for electronic equipment.

  Further, by forming a microlens corresponding to each pixel on the counter substrate 20, the light collection efficiency of incident light with respect to the pixel electrode 9a can be increased, so that bright display can be performed. Furthermore, a dichroic filter that produces RGB colors using the interference action of light may be formed by stacking multiple layers of interference layers having different refractive indexes on the counter substrate 20. According to the counter substrate with the dichroic filter, brighter color display can be performed.

(Configuration and operation of liquid crystal device)
Next, the electrical configuration and operation of an active matrix liquid crystal device (electro-optical device) will be described with reference to FIGS.

  FIG. 5 is an equivalent circuit diagram of various elements and wirings in a plurality of pixels formed in a matrix to constitute an image display region of the liquid crystal device. FIG. 6 is a plan view of adjacent pixels on an active matrix substrate on which data lines, scanning lines, pixel electrodes, and the like are formed. FIG. 7 is an explanatory view showing a cross section at a position corresponding to the line AA ′ in FIG. 6 and a cross section in a state where liquid crystal as an electro-optical material is sealed between the active matrix substrate and the counter substrate. In these drawings, the scales are different for each layer and each member so that each layer and each member can be recognized on the drawing.

  As shown in FIG. 5, in the image display area of the liquid crystal device, each of a plurality of pixels formed in a matrix has a pixel electrode 9a and a pixel switching MIS transistor 30 for controlling the pixel electrode 9a. Is formed. A data line 6 a for supplying a pixel signal is electrically connected to the source of the MIS transistor 30. Pixel signals S1, S2,... Sn written to the data line 6a are supplied line-sequentially in this order. Further, the scanning line 3a is electrically connected to the gate of the MIS transistor 30, and the scanning signals G1, G2,... Gm are pulse-sequentially applied to the scanning line 3a in this order at a predetermined timing. It is comprised so that it may apply. The pixel electrode 9a is electrically connected to the drain of the MIS transistor 30, and the pixel signal S1 supplied from the data line 6a by turning on the MIS transistor 30 serving as a switching element for a certain period. S2... Sn is written to each pixel at a predetermined timing. In this way, the pixel signals S1, S2,... Sn at a predetermined level written to the liquid crystal via the pixel electrode 9a are held for a certain period with a counter electrode formed on a counter substrate described later.

  Here, in order to prevent the held pixel signal from leaking, a storage capacitor 70 (capacitor) may be added in parallel with the liquid crystal capacitor formed between the pixel electrode 9a and the counter electrode. The storage capacitor 70 holds the voltage of the pixel electrode 9a for a time that is, for example, three orders of magnitude longer than the time when the source voltage is applied. As a result, a charge retention characteristic is improved, and a liquid crystal device capable of performing display with a high contrast ratio can be realized. The storage capacitor 70 may be formed between the capacitor line 3b, which is a wiring for forming a capacitor, or may be formed between the storage line 70 and the preceding scanning line 3a.

  In FIG. 6, on the active matrix substrate of the liquid crystal device, a plurality of transparent pixel electrodes 9a (regions surrounded by dotted lines) are formed for each matrix pixel, and along the vertical and horizontal boundary regions of the pixel electrodes 9a. A data line 6a, a scanning line 3a, a capacitance line 3b, and a MIS transistor 30 are formed.

As shown in FIG. 7, the liquid crystal device includes an active matrix substrate 10 and a counter substrate 20 disposed to face the active matrix substrate 10.
The base of the active matrix substrate 10 is made of a transparent substrate 10b such as a quartz substrate or a heat resistant glass plate. An interlayer insulating film 12 is formed on the surface side of the substrate, and a MIS type transistor 30 for pixel switching for switching control of each pixel electrode 9a is formed on the surface side of the interlayer insulating film 12. The above configuration of the active matrix substrate 10 is realized by adopting the above-described composite semiconductor substrate 600. 7 corresponds to the support substrate 500 in FIG. 2D, the interlayer insulating film 12 in FIG. 7 corresponds to the insulating layer 550 in FIG. 2D, and the semiconductor layer 1a in FIG. This corresponds to the single crystal silicon layer 220 in FIG. As shown in FIG. 7, a light shielding film 11 a made of a chromium film or the like is formed between the transparent substrate 10 b and the interlayer insulating film 12. The light shielding film 11a is formed in a region overlapping the MIS transistor 30 in a plan view so that return light can be prevented from entering the MIS transistor 30.

  As shown in FIG. 7, the MIS transistor 30 described above has an LDD (Lightly Doped Drain) structure, and a channel region 1a ′ in which a channel is formed in the semiconductor layer 1a by an electric field from the scanning line 3a. A low concentration source region 1b, a low concentration drain region 1c, a high concentration source region 1d, and a high concentration drain region 1e are formed. A gate insulating film 2 for insulating the semiconductor layer 1a and the scanning line 3a is formed on the upper side of the semiconductor layer 1a.

Interlayer insulating films 4 and 7 made of a silicon oxide film are formed on the surface side of the MIS transistor 30 configured as described above. A data line 6 a is formed on the surface of the interlayer insulating film 4, and the data line 6 a is electrically connected to the high concentration source region 1 d through a contact hole formed in the interlayer insulating film 4. A pixel electrode 9 a made of a transparent conductive thin film such as an ITO (Indium Tin Oxide) film is formed on the surface of the interlayer insulating film 7. The pixel electrode 9a is electrically connected to the high-concentration drain region 1e through contact holes formed in the interlayer insulating films 4 and 7 and the gate insulating film 2. On the surface side of the pixel electrode 9a, an alignment film 16 is formed by rubbing the polyimide film.
Note that the capacitor line 3b (upper electrode) in the same layer as the scanning line 3a is formed at the same time as the gate insulating film 2 with respect to the extending portion 1f (lower electrode) from the high-concentration drain region 1e. The body membrane is opposed to each other. Thereby, the storage capacitor 70 is configured.

  On the other hand, the base of the counter substrate 20 is made of a transparent substrate 20b such as a quartz substrate or a heat-resistant glass plate. A light shielding film 23 is formed on the surface side of the transparent substrate 20b, and a counter electrode 21 made of ITO or the like is formed on the surface side of the light shielding film 23. An alignment film 22 is also formed on the upper side of the counter electrode 21 by rubbing the polyimide film.

  The active matrix substrate 10 and the counter substrate 20 configured as described above are arranged so that the pixel electrode 9a and the counter electrode 21 face each other. A liquid crystal 50 as an electro-optical material is sealed in a space surrounded by each of these substrates and the sealing material. The liquid crystal 50 is made of, for example, one or a mixture of several types of nematic liquid crystals, and takes a predetermined alignment state by the alignment films 16 and 22 in a state where an electric field from the pixel electrode 9a is not applied.

  On the outside of the counter substrate 20 and the active matrix substrate 10, the type of liquid crystal 50 to be used, that is, an operation mode such as a TN (twisted nematic) mode, an STN (super TN) mode, or a normally white mode / normally. Depending on the black mode, a polarizing film, a retardation film, a polarizing plate, and the like are arranged in a predetermined direction.

  As described in detail above, the liquid crystal device according to the second embodiment is configured to include the composite semiconductor substrate formed using the method for manufacturing the electro-optical device according to the first embodiment. By using the method for manufacturing the electro-optical device according to the first embodiment, it becomes possible to repair lattice defects and the like of the semiconductor layer, and thus it is possible to provide an electro-optical device with excellent display quality. In addition, the semiconductor layer can be prevented from being broken and the yield is improved, so that a low-cost electro-optical device can be provided.

[Electronics]
Next, a projection type liquid crystal display device which is an example of an electronic apparatus including an electro-optical device will be described with reference to FIGS.
First, FIG. 8 is a block diagram illustrating a configuration of an electronic apparatus including the liquid crystal device 100 configured similarly to the electro-optical device according to each of the above embodiments.

  In FIG. 8, the electronic device includes a display information output source 1000, a display information processing circuit 1002, a drive circuit 1004, a liquid crystal device 100, a clock generation circuit 1008, and a power supply circuit 1010. The display information output source 1000 includes a ROM (Read Only Memory), a RAM (Random Access Memory), a memory such as an optical disk, a tuning circuit that tunes and outputs an image signal of a television signal, and the like, and a clock generation circuit 1008. The image signal of a predetermined format is processed on the basis of the clock signal from the signal and output to the display information processing circuit 1002. The display information processing circuit 1002 includes various known processing circuits such as an amplification / polarity inversion circuit, a phase expansion circuit, a rotation circuit, a gamma correction circuit, or a clamp circuit, and is input based on a clock signal. A digital signal is sequentially generated from the display information and is output to the drive circuit 1004 together with the clock signal CLK. The drive circuit 1004 drives the liquid crystal device 100. The power supply circuit 1010 supplies predetermined power to the above-described circuits. Note that the driver circuit 1004 and the display information processing circuit 1002 may be formed over the active matrix substrate included in the liquid crystal device 100.

  As an electronic apparatus having such a configuration, a projection type liquid crystal display device (liquid crystal projector) illustrated in FIG. 9 can be given. In the projection type liquid crystal display device 1100 shown in FIG. 9, the liquid crystal module including the liquid crystal device 100 described above is employed as the RGB light valves 100R, 100G, and 100B. In this liquid crystal projector 1100, when light is emitted from a lamp unit 1102 of a white light source such as a metal halide lamp, light corresponding to the three primary colors R, G, and B is emitted by three mirrors 1106 and two dichroic mirrors 1108. The light components are separated into components R, G, and B (light separating means) and led to the corresponding light valves 100R, 100G, and 100B (liquid crystal device 100 / liquid crystal light valve). At this time, since the optical component B has a long optical path, the light component B is guided through a relay lens system 1121 including an incident lens 1122, a relay lens 1123, and an exit lens 1124 in order to prevent light loss. Then, the light components R, G, and B corresponding to the three primary colors respectively modulated by the light valves 100R, 100G, and 100B are incident on the dichroic prism 1112 (light combining unit) from three directions and are combined again, and then the projection lens. A color image is projected on a screen 1120 or the like via 1114.

  The projection display device described in detail above is configured to include the electro-optical device according to the second embodiment. According to this configuration, since a low-cost electro-optical device with excellent display quality is employed, a low-cost projection display device with excellent display quality can be provided.

The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, the specific configuration of the liquid crystal device described as the embodiment is merely an example, and the present invention can be applied to a liquid crystal device having various other configurations. The present invention also relates to an electro-optical device using various electro-optical elements using electroluminescence (EL), a digital micromirror device (DMD, registered trademark), or fluorescence using plasma emission or electron emission, and the electro-optical device. Needless to say, the present invention can also be applied to an electronic device equipped with the above. Furthermore, the present invention can also be applied to optical elements such as optical switches.
Further, the single crystal semiconductor layer in the present invention is not limited to single crystal silicon, and for example, single crystal germanium can be used.

It is process sectional drawing which shows the manufacturing method of a composite semiconductor substrate. It is process sectional drawing which shows the manufacturing method of a composite semiconductor substrate. It is a top view at the time of seeing a liquid crystal device from the counter substrate side. It is HH 'sectional drawing of FIG. 3 shown including a counter substrate. It is an equivalent circuit diagram in the image display area of the liquid crystal device. It is a top view of the pixel which mutually adjoins in an active matrix substrate. It is side surface sectional drawing in the position corresponded to the AA 'line of FIG. It is a block diagram of the electronic device provided with the liquid crystal device. It is a schematic block diagram of the projection type liquid crystal display device which is an example of an electronic device.

Explanation of symbols

  220 semiconductor layer 500 support substrate

Claims (10)

Attaching a semiconductor substrate to the surface of the support substrate;
Thinning the semiconductor substrate and forming a semiconductor layer on the surface of the support substrate;
Irradiating the semiconductor layer with a laser having an absorption wavelength by the semiconductor layer to melt a surface layer portion of the semiconductor layer; and
A method for manufacturing an electro-optical device. The method of manufacturing an electro-optical device according to claim 1, wherein the support substrate and the semiconductor layer are made of materials having different thermal expansion coefficients. The method of manufacturing an electro-optical device according to claim 1, wherein the laser irradiation of the semiconductor layer is performed so as to scan the semiconductor layer. 4. The method of manufacturing an electro-optical device according to claim 1, wherein the laser irradiation of the semiconductor layer is performed only on a semiconductor element formation region in the semiconductor layer. 5. The method of manufacturing an electro-optical device according to claim 1, wherein the thinning of the semiconductor substrate is performed by separating the semiconductor substrate in a hydrogen ion implantation layer of the semiconductor substrate. . 6. The method of manufacturing an electro-optical device according to claim 1, wherein the laser irradiation of the semiconductor layer is performed while focusing on a surface of the semiconductor layer. The method of manufacturing an electro-optical device according to claim 1, wherein the laser is an excimer laser. The method of manufacturing an electro-optical device according to claim 1, wherein the laser is a continuous wave argon laser. An electro-optical device manufactured using the method for manufacturing an electro-optical device according to claim 1. An electronic apparatus comprising the electro-optical device according to claim 9.

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