KR20100089541A - Plasma enhanced chemical vapor deposition apparatus - Google Patents

Abstract

PURPOSE: A plasma enhanced chemical vapor deposition apparatus is provided to increase the uniformity of film by extending the distance between a substrate and a discharge electrode. CONSTITUTION: A discharge electrode unit(110) is linearly arranged near center of a processing chamber(10). A plurality of ground electrodes(121) are respectively arranged in longitudinal direction at both sides of the discharge electrode unit. The discharge electrode unit comprises a plurality of linear electrode rods(111). A plurality of holes(112) are formed in the electric rod. Each ground electrode unit is arranged at both sides of the discharge unit by a creation interval between them.

Description

Plasma Chemical Vapor Deposition Apparatus {PLASMA ENHANCED CHEMICAL VAPOR DEPOSITION APPARATUS}

The present invention relates to a plasma chemical vapor deposition apparatus.

Plasma enhanced chemical vapor deposition (PECVD) devices are used to form semiconductor layers such as amorphous silicon, microcrystalline silicon, polycrystalline thin film silicon, and silicon nitride used in solar cells, thin film transistors, etc., or to etch portions of the formed film. do.

The PECVD apparatus uses a radio frequency (RF) of about 13.56 MHz, but uses a very radio frequency (VRF) of about 27 MHz or more to improve reaction speed and film characteristics such as deposition rate and etching rate. Sometimes.

When forming a film on a desired substrate or etching the formed film by using a PECVD apparatus using radio frequency or ultra high frequency, the distance between the discharge electrode and the substrate for plasma formation is as narrow as possible, for example, about 10 mm or less to improve the reaction speed. I was.

However, as the distance between the discharge electrode and the substrate becomes narrower, the reaction speed is improved, but a problem arises in that the degree of formation or etching of the film formed by the non-uniform diffusion degree of the process gas discharged from the discharge electrode varies depending on the position. As a result, the closer the distance between the substrate and the discharge electrode is, the faster the reaction speed is, but the film characteristics are reduced, resulting in a problem in that the operation performance of the PECVD apparatus is lowered.

The technical problem to be achieved by the present invention is to improve the performance of the PECVD apparatus.

Another technical problem to be achieved by the present invention is to improve the productivity of a PECVD apparatus.

A plasma chemical vapor deposition apparatus according to an aspect of the present invention is supplied with power of a predetermined size, facing at least one first electrode portion having a plurality of electrodes, and facing each first electrode portion, It includes a plurality of second electrode portion which is disposed spaced apart from the one electrode portion by a predetermined distance.

The first electrode portion and the plurality of second electrode portions may be disposed in the longitudinal direction of the process chamber.

Preferably, the substrate is disposed on each side of the two second electrode portions facing the first electrode portion.

The predetermined distance may be about 10 mm to 50 mm.

The power source may include a first power source and a second power source having a phase difference of 0 ° to 180 °.

Preferably, the first power and the second power are alternately applied to one end of the plurality of electrodes.

The amount of power supplied to each electrode of the first electrode part based on the first power source and the second power source may be about 3kW to 10kW.

The other end of the plurality of electrodes of the first electrode portion to which the first power source or the second power is not applied may be floating or grounded.

Preferably, the second electrode part includes a heater part.

Each electrode of the first electrode portion may include a plurality of holes through which process gas passes.

Each electrode of the first electrode unit may further include a hole through which a coolant passes.

Each electrode of the first electrode part may have a cylindrical shape or a polygonal column shape.

Each electrode may be made of a conductive material, and the surface of each electrode may have a structure coated with an insulating material.

The conductive material may be made of at least one of anodized aluminum, steel special use stainless steel, and a metal material.

The insulating material may be made of at least one of SiO ₂ , Al ₂ O ₃ , ZiO ₂ , quartz, and teflon.

The first electrode unit may be two or more.

Preferably, the first electrode portion and the second electrode portion are alternately arranged, and the number of the second electrode portions is one more than the number of the first electrode portions.

The substrate may be disposed on each side of the two second electrode portions facing the first electrode portions.

Preferably, the plurality of second electrode portions are grounded.

According to the characteristics of the present invention, since the distance between the substrates in the first electrode portion is widened, the degree of deposition or etching degree is improved, and the number of substrates to be manufactured is increased, thereby improving productivity of the plasma chemical vapor deposition apparatus.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like parts throughout the specification.

Throughout the specification, when a part is "connected" to another part, this includes not only "directly connected" but also "electrically connected" with another element in between. .

Throughout the specification, when a part is said to "include" a certain component, it means that it can further include other components, without excluding other components unless specifically stated otherwise. In addition, the terms “… unit”, “… unit”, “module”, etc. described in the specification mean a unit that processes at least one function or operation, which may be implemented by hardware or software or a combination of hardware and software. have.

In the drawings, the thickness of layers, films, panels, regions, etc., are exaggerated for clarity. Like parts are designated by like reference numerals throughout the specification. When a layer, film, region, plate, or the like is referred to as being "on" another portion, it includes not only the case directly above another portion but also the case where there is another portion in between. On the contrary, when a part is "just above" another part, there is no other part in the middle. In addition, when a part is formed "overall" on another part, it means that not only is formed on the entire surface (or front) of the other part but also is not formed on the edge part.

Next, a PECVD apparatus according to an embodiment of the present invention will be described with reference to the accompanying drawings.

1 is a perspective view schematically showing a PECVD apparatus according to an embodiment of the present invention.

As shown in FIG. 1, the PECVD apparatus 1 according to an embodiment of the present invention has a discharge electrode part 110 disposed in the process chamber 10 in the longitudinal direction, that is, parallel to the side surface of the process chamber 10. A plurality of ground electrode parts 121 are disposed on both sides of the discharge electrode part 110 in the vertical direction so as to face the discharge electrode part 110.

The discharge electrode portion 110 is disposed in a straight line A near the center of the process chamber 10 and extends from the upper portion 11 to the lower portion 12 of the process chamber 10.

The discharge electrode unit 110 includes a plurality of straight discharge electrodes 111. In FIG. 1, since each discharge electrode 111 has an electrode having a circular shape, it is hereinafter referred to as an electrode. Alternatively, however, the electrode may have various shapes such as a polygonal column shape such as a rectangular or square rectangular column.

 Each electrode 111 has a space in which process gas injected from the outside through the injection hole 130 is injected into the electrode 111. In this embodiment, each electrode 111 may be formed with at least one cooling hole (not shown) through which a coolant, such as water, is injected and discharged along the longitudinal direction of the electrode 111.

A plurality of holes 112 are formed in each electrode 111. Therefore, the process gas injected from the outside is discharged into the process chamber 10 through the hole 112 and diffused toward each substrate 140 facing the discharge electrode unit 110.

In FIG. 1, the plurality of electrode rods 111 receive the process gas through one injection hole 130, but, alternatively, the plurality of electrode rods 111 may receive the process gas through two or more injection holes. For example, injection holes may be connected to each electrode 111, or a predetermined number of electrodes 111 may be connected to one injection hole.

Each electrode 111 is made of a conductive material, and the surface thereof is coated with an insulating material or the like, such as a ceramic coating using a ceramic material. In this case, the coating thickness of the insulating material is several tens of micrometers to several hundred micrometers, and may be a thickness that does not affect the plasma generation operation of the electrode 111. Examples of the conductive material may be anodized aluminum, steel special use stainless, or metal material, and the insulating material may be SiO ₂ , Al ₂ O ₃ , ZiO ₂ , quartz, teflon, and the like. For this reason, the electrode rod 111 is prevented from being damaged by the plasma formed inside the process chamber 10. In addition, the plasma may prevent the material attached to the surface of each electrode 111 from falling toward the substrate 140 and contaminating the substrate 140.

The discharge electrode unit 110 receives two power sources having a predetermined phase difference at a predetermined time and receives power of a corresponding size. In this case, the magnitude of the applied power may be about 3 to 10 kW, and the phase difference between the powers may be about 0 to 180 degrees.

One ground electrode part 121 is disposed on both sides of the discharge electrode part 110 at a predetermined distance. These ground electrode portions 121 are disposed on the side surfaces of the discharge electrode portion 110, respectively, and are grounded by a conductive material such as metal. Each ground electrode portion 121 is provided with a heater therein. Therefore, the heater is embedded in a case made of a conductive material such as metal, and grounded. Due to the grounding of each ground electrode portion 121, the potential of the ground electrode portion 121 is stably fixed without changing according to the potential state of the opposing discharge electrode portion 110, and thus the process chamber wall surface and the ground electrode portion 121 are fixed. To prevent the generation of plasma that may be generated in an unnecessary place such as Alternatively, however, the ground electrode 121 may be floated.

The distance between the discharge electrode 110 and the ground electrode 121 may be equal to each other, and may be about 10 nm to 50 nm.

Each ground electrode portion 121 generates heat. At this time, the temperature of the process chamber 10 rises to about 200 ° C by the operation of each ground electrode part 121.

Although not shown in FIG. 1, the process chamber 10 includes at least one exhaust port for maintaining a constant pressure inside the process chamber.

Next, a driving unit of the PECVD apparatus will be described with reference to FIG. 2.

2 is a block diagram of a driving unit of a PECVD apparatus according to an embodiment of the present invention.

As shown in FIG. 2, the driving unit of the PECVD apparatus according to the exemplary embodiment of the present invention includes a phase shifter 210, a first power supply 221 connected to the phase shift 210, and a first power supply unit ( A first impedance matching unit 222 connected to 221, a first power distribution unit 223 connected to the first matching unit 222, a second power supply unit 231 connected to the phase shift 210, and a second power supply unit 231 connected to the phase shift 210. 2, a second matching unit 232 connected to the power supply unit 231, and a second power distribution unit 233 connected to the second matching unit 232.

The phase shifter 210 includes a first power supply 221 and a second power supply 231 such that phase values of power output from the first power supply 221 and the second power supply 231 are 0 to 180 °, respectively. To control the operation.

The first and second power supply units 221 and 231 respectively supply power having the same size to the discharge electrode unit 110 by applying power of the same size having a phase difference determined by the operation of the phase shifter 210.

The first and second matching units 222 and 232 adjust the impedance difference between the input terminal and the output terminal, respectively, so that the power applied from the first and second power supply units 221 and 231 efficiently discharge electrode unit 110. To be approved).

The first power distributor 223 and the second power distributor 233 are connected to one end of the electrode 111 adjacent to each other. For example, when the first power distribution unit 223 is connected to one end of the odd-numbered electrode 111, the second power distribution unit 233 is connected to one end of the even-numbered electrode 111 and vice versa. When the first power distributor 223 is connected to one end of the even electrode 111, the second power distributor 233 is connected to one end of the odd electrode 111. In FIG. 2, the other end of the electrode 111 that is not connected to the first and second power distribution units 223 and 233 is floating but may be grounded. When the other end of the electrode 111 is grounded, a current flows in each electrode 111 to form a magnetic field around the electrode 111, thereby forming an inductively coupled plasma to form a plasma density. It can increase.

The first and second power distribution units 223 and 233 equally compensate for the difference in distance between the corresponding first or second power supply units 221 and 231 and the electrode rods 111 respectively connected to the first or second power supply units. Power supply distances between the electrodes 221 and 231 and the connected electrode rods 111 are the same. As a result, a malfunction due to a difference in power supply time or a phase difference due to a distance difference between the first or second power supply units 221 and 231 and the electrode rods 111 is prevented.

The operation of the PECVD apparatus having such a structure will be described with reference to FIGS. 1 and 2.

First, the first and second power supply units 221 and 231 output power of a predetermined size. That is, the first power supply 221 outputs the first power, and the second power supply 231 outputs the second power. The output first and second power sources are input to the first and second matching units 222 and 232, respectively, and impedance matching is performed, and then the electrode rods 111 connected through the first and power power distribution units 223 and 233, respectively. Is applied to one end of the) to supply power of the corresponding size to the electrode 111. In this embodiment, the frequencies of the first and second power sources may be radio frequency to ultra high frequency.

As such, power having a phase difference of a predetermined size is applied to adjacent electrode rods 111 and thus power of the corresponding size is supplied to adjacent electrode rods 111, between the electrode rods 111 and between the electrode rods 111 and the substrate 140. Plasma is generated.

In the present embodiment, the magnitude of power applied to the electrodes 111 adjacent to each other is the same but may be different. For example, the magnitude of power applied to each electrode 111 may range from about 3 to 10 kW. In this case, the sizes of the first and second power sources output from the first and second power supply units 221 and 231 may vary according to the plasma density to be generated. In addition, in the present embodiment, the phase difference between the first and second power supplies output from the first and second power supply units 221 and 231 is about 0 to 180 degrees. For example, the phase difference between the first and second power sources output from the first and second power supply units 221 and 231 varies according to the plasma formation position. As an example, when the phase difference between the first and second power supplies output from the first and second power supply units 221 and 231 is 0 °, the plasma is formed at the center of the electrode 111. At this time, the plasma is formed in a direction perpendicular to the electrode 111. In this state, the plasma formation position moves in accordance with the magnitude of the phase difference between the first and second power sources.

When the position at which the plasma is formed is fixed at any one portion, the decomposition operation of the process gas becomes more active at the portion where the plasma is formed, so that the process speed at the portion where the plasma is formed is different from the portion where the plasma is not formed. As a result, the thickness or etching degree of the film formed on the substrate 140 is different from each other. Therefore, in this embodiment, since the plasma formation position is changed periodically by changing the phase difference between the first and second power sources at a predetermined time period, plasma is uniformly formed regardless of the position.

Therefore, when a process gas for stacking or etching a film is injected into the vacuum process chamber 10, the process gas is decomposed by the generated plasma and heat to form a film on the substrate 140 or to remove a desired portion. In this case, the substrate 140 may be a substrate such as a semiconductor, glass, metal, or a flexible substrate such as plastic.

As described above, since the formation position of the plasma is changed according to the phase difference between the first and second power sources, the thickness or etching degree of the film formed on the entire surface of the substrate 140 is uniform.

Furthermore, since the distance between the substrate 140 and the discharge electrode unit 110 is about 10 mm to 50 mm wider than that of the conventional 7.5 mm, the diffusion range of the process gas discharged from each electrode 111 is also widened. The uniformity of the thickness and the etching degree of the film is improved compared to the prior art. In addition, as the distance between the substrate 140 and the discharge electrode unit 110 increases, the influence of heat generated by the operation of the discharge electrode unit 110 on the substrate 140 decreases, thereby cooling the electrode 111. Remove a separate cooling device, such as a cooling conduit, or simplify the structure of the cooling device.

In the PECVD apparatus according to the present exemplary embodiment, since the ground electrode parts 121 are disposed on both sides of the discharge electrode part 110, the two substrates 140 are processed in one process. The productivity can be improved.

In addition, since the distance between the substrate 140 and the discharge electrode unit 110 is about 10 mm to 50 mm, the diffusion distribution range of the process gas is widened to improve the uniformity of the film formation degree and the etching degree.

Next, another example of a PECVD apparatus according to an embodiment of the present invention will be described with reference to FIG. 3. Components that perform the same function as the PECVD apparatus 1 described with reference to FIG. 1 are given the same reference numerals and detailed description thereof will be omitted.

3 is a schematic perspective view of another example of a PECVD apparatus according to an embodiment of the present invention.

Referring to FIG. 3, the PECVD apparatus 1a according to the example of the present embodiment is similar to the PECVD apparatus 1 shown in FIG. 1, and has a discharge electrode unit 110 and a ground electrode inside the process chamber 10. The part 121 is provided.

However, unlike the example shown in FIG. 1, in this example, the number of discharge electrode units 110 is two, and each discharge electrode unit 110 has a separate injection hole 130 connected thereto. In addition, one ground electrode part 121 is disposed between the two discharge electrode parts 110. That is, the discharge electrode part 110 and the ground electrode part 121 are alternately arranged, and the number of the ground electrode part 121 is one more than the number of the discharge electrode part 110. At this time, except for the ground electrode portion 121 disposed immediately adjacent to the leftmost portion and the rightmost portion of the discharge chamber 10, the substrate 140 is disposed on both surfaces of the remaining ground electrode portion 121, respectively. do. That is, the substrate 140 is disposed on both surfaces of one ground electrode 121 disposed between two discharge electrode portions 110. As a result, the substrate 140 is disposed on each surface of the two ground electrode parts 121 facing the one discharge electrode part 110. Accordingly, in the case of FIG. 3, the number of substrates 140 produced in one step is four, and the substrate manufacturing speed is improved.

Although the PECVD apparatus 1a shown in FIG. 3 includes two discharge electrode portions 110 and three ground electrode portions 121 in one process chamber 10, the PECVD apparatus 1a illustrated in FIG. According to the number of substrates 140, three or more discharge electrode units 110 and four or more ground electrode units 121 may be provided in one process chamber 10. Also in this case, the discharge electrode 110 and the ground electrode 121 are alternately arranged, and the number of the ground electrode 121 is greater than the number of the discharge electrode 110.

At this time, for the operation of each discharge electrode unit 110, the PECVD driving unit for supplying the first and second power to each electrode 111 connected to each other having a predetermined phase difference is the same as shown in Figure 2, each discharge electrode unit Since the operation of generating the plasma between the corresponding ground electrode part 121 by driving the 110 is also the same as that described with reference to FIG. 2, a detailed description thereof will be omitted.

In the PECVD apparatus described with reference to FIG. 3, the distance between the substrate 140 and the discharge electrode unit 110 becomes wider, resulting in uniformity in film formation or etching, and in addition, a substrate manufactured in one process chamber 1a. Since the number of 140 is three or more, the board | substrate manufacturing speed further improves.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

1 is a perspective view schematically showing a PECVD apparatus according to an embodiment of the present invention.

  2 is a block diagram of a driving unit of a PECVD apparatus according to an embodiment of the present invention.

3 is a schematic perspective view of another example of a PECVD apparatus according to an embodiment of the present invention.

Claims (19)

At least one first electrode unit having a predetermined size of power and having a plurality of electrodes, and A plasma chemical vapor deposition apparatus comprising a plurality of second electrode portions facing each first electrode portion, the second electrode portions being disposed spaced apart from each of the first electrode portions by a predetermined distance. In claim 1, And the first electrode portion and the plurality of second electrode portions are arranged in the longitudinal direction of the process chamber. In claim 2, And a substrate disposed on each side of the two second electrode portions facing the first electrode portion. In claim 1, And said constant distance is about 10 mm to 50 mm. In claim 1, The power supply is a plasma chemical vapor deposition apparatus comprising a first power supply and a second power supply having a phase difference of 0 to 180 °. In claim 5, And the first power source and the second power source are alternately applied to one end of the plurality of electrodes of the first electrode unit. In claim 6, The amount of power supplied to each electrode of the first electrode unit based on the first power source and the second power source is about 3kW to 10kW. In claim 6, And other ends of the plurality of electrodes of the first electrode portion to which the first power source or the second power source is not applied are floating or grounded. In claim 1, And the second electrode part comprises a heater part. In claim 1, And each electrode of the first electrode portion includes a plurality of holes through which a process gas passes. In claim 10, And each electrode of the first electrode portion further comprises a hole through which a coolant passes. In claim 1, And each electrode of the first electrode portion has a cylindrical shape or a polygonal column shape. In claim 12, Each electrode is made of a conductive material, the surface of each electrode having a structure coated with an insulating material plasma chemical vapor deposition apparatus. The method of claim 13, The conductive material is a plasma chemical vapor deposition apparatus consisting of at least one of anodized aluminum, steel special use stainless (SUS) and metal materials. The method of claim 13, The insulating material is a plasma chemical vapor deposition apparatus consisting of at least one of SiO ₂ , Al ₂ O ₃ , ZiO ₂ , quartz and teflon. In claim 1, And at least two first electrode portions. The method of claim 16, And the first electrode portion and the second electrode portion are alternately arranged, and the number of the second electrode portions is one more than the number of the first electrode portions. The method of claim 17, And a substrate disposed on each side of the two second electrode portions facing the first electrode portions. In claim 1, And the plurality of second electrode portions are grounded.

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