KR20050058095A - Process apparatus using plasma which injects and vents proocess gas through inner side wall of process chamber, and method of processing a substrate using the same - Google Patents

Abstract

The present invention provides a chamber for forming a constant reaction space therein; a first injection port formed on one sidewall of the chamber and spraying a process gas; A first exhaust port formed on a side wall facing the injection port and discharging exhaust gas; A susceptor positioned inside the chamber and for placing a substrate on an upper surface thereof; Located on top of the susceptor, there is provided a process equipment using a plasma comprising a plasma electrode connected to the RF power supply for supplying RF power, and a method of treating a substrate using the same.

According to the present invention, it is possible to eliminate expensive showerheads and to minimize the space in which gas is supplied, thereby improving vacuum uniformity on the surface of the substrate located inside the chamber, as well as saving process gas or cleaning gas. Cost reduction and productivity improvement can be achieved.

In addition, according to the present invention it is possible to improve the uniformity of the process by improving the uniformity of the process gas supplied into the chamber.

Description

Process apparatus using plasma which injects and vents proocess gas through inner side wall of process chamber, and method of processing a substrate using the same}

The present invention relates to a process equipment using plasma, and more particularly to a process equipment for injecting and discharging process gas from the side wall of the chamber.

In general, in order to manufacture a liquid crystal display device or a semiconductor wafer (hereinafter referred to as a substrate), a thin film deposition process for depositing a dielectric material or the like on a substrate as a thin film, or using a photosensitive material to expose or conceal selected areas of the thin film. The photolithography process, the etching process of removing the thin film of the selected region and patterning as desired, the washing process to remove the residue, etc. must be repeated several times. The optimal environment is carried out inside the chamber.

FIG. 1 is a schematic diagram illustrating an internal configuration of a PECVD apparatus for thin film deposition using plasma among equipment for manufacturing such a substrate, and includes a chamber 10 and a chamber 10 for forming a constant reaction space therein. ) Is located inside the susceptor 20 to position the substrate 40 on the upper surface and to move up and down, the shower head 70 for injecting the process gas from the upper portion of the susceptor 20, the external gas supply ( It is connected to the (not shown) includes a gas inlet pipe 90 for introducing the process gas to the shower head 70, and the edge frame 60 located on the frame support 50 of the inner wall of the chamber 10. A lift pin (not shown) is coupled to the susceptor 20 to settle the substrate.

In addition, an RF power supply 80 for supplying RF power for generating plasma is connected to a plasma electrode or an antenna. In the drawing, the plasma electrode is integrally formed with the shower head 70, and the RF power is applied to the center of the electrode. In order to connect the RF power supply 80 to the gas supply pipe (90). In order to control the energy of the plasma incident on the substrate 40, a separate RF power source may also be applied to the susceptor 20.

The shower head 70 has a buffer space 74 formed to uniformly diffuse inside the shower head 70 before the process gas introduced through the gas supply pipe 90 is injected, and a lower nozzle part including a number of through holes. And 72.

The susceptor 20 generally includes a heater (not shown) therein for preheating or heating the substrate 40 placed on the upper surface.

Looking at the process of loading the substrate 40 to the process position in the process chamber 10 having such a configuration, first, when the substrate 40 is placed on top of the susceptor 20 by a robot arm (not shown), The susceptor 20 rises to the process position, while the edge frame 60 mounted on the frame support 50 on the inner wall of the chamber rises together while pressing the edge of the substrate. The reason why the susceptor 20 is raised to the upper portion of the chamber as described above is to prevent adverse effects on the process uniformity due to an exhaust port (not shown) located below.

When the substrate 40 is placed in the process position, the process gas is injected through the shower head 70, and then RF power is applied to transfer the process gas into plasma active species having strong oxidizing power. The active paper performs a thin film deposition process on the substrate 40, and in order to constantly flow the process gas, the process gas is discharged at a constant flow rate through the exhaust port 30 in the lower part of the chamber during the process.

After the deposition process is performed for a predetermined time, the residual gas is discharged through the exhaust port, and then the susceptor 20 is lowered and the substrate 40 is carried out from the process chamber 10.

However, since the uniformity of the process gas injected from the shower head 70 depends on the size and shape of the through hole of the nozzle unit 72, the through hole should be made as uniform as possible. Recently, especially in the case of LCD manufacturing equipment, as the substrate 40 becomes large, the area of the shower head 70 is increased together, and thus, more through holes must be drilled, and it is easy to drill tens of thousands of through holes to the same size. Not only that, there is a problem in that the price of the shower head 70 increases significantly due to the difficulty of processing technology.

In addition, when spraying the process gas using the shower head 70, in order to reduce the influence on the process by the exhaust port (not shown) formed in the lower, the susceptor is raised to the upper process position to proceed the process. As a result, the process gas flows into the space formed under the susceptor, resulting in waste of the process gas. In addition, since unnecessary deposition occurs on the sidewall of the susceptor 20 or the inner wall of the chamber 100 due to the influence of plasma active species, the cleaning gas is processed in the process chamber even when in-situ cleaning is performed. There is an inefficient problem that must be supplied throughout.

On the other hand, the RF power applied to the plasma electrode forms a standing wave of a constant wavelength on the surface of the plasma electrode, which is inevitable phenomenon that the RF power is uneven depending on the position, this non-uniformity of the RF power affects the process uniformity Go crazy. Conventionally, since the plasma electrode has a relatively small size compared to the standing wave wavelength, such an effect can be ignored. However, in recent years, the LCD substrate has been forced to consider such an influence as the size of the LCD substrate is enlarged. The provision of urgent situation is also urgent.

The present invention is to solve this problem, by minimizing the space supplied with the process gas or cleaning gas, to improve the productivity through cost reduction, while providing a process equipment that can improve the process uniformity of large area substrate Its purpose is to.

In order to achieve the above object, the present invention provides a chamber for forming a constant reaction space therein: a first injection port formed on one sidewall of the chamber and for injecting a process gas; A first exhaust port formed on a side wall facing the injection port and discharging exhaust gas; A susceptor positioned inside the chamber and for placing a substrate on an upper surface thereof; It is provided on the top of the susceptor, and provides a process equipment using a plasma including a plasma electrode connected to the RF power supply for supplying RF power.

A second exhaust port is formed on the sidewall on which the first injection port is formed, and a process equipment using plasma is formed on the sidewall on which the first exhaust port is formed.

The first injection port and the second injection port provide a process equipment using a plasma having a rectangular slit shape.

The first injection port and the second injection port provide a process equipment using a plasma formed by a plurality of injection holes.

The first exhaust port and the second exhaust port provide a process equipment using a plasma formed by a plurality of exhaust holes.

An inner edge of the chamber is provided with an edge frame for pressing the edge of the substrate placed in the susceptor, the lower surface of the edge frame is a process equipment using a plasma (sealing) is formed to prevent the leakage of process gas to provide.

At least one of the susceptor or the plasma electrode is provided with a process equipment using a plasma is formed a heater for preheating the substrate.

The plasma electrode provides a process equipment using a plasma composed of a plurality of electrode blocks.

The plurality of electrode blocks provide a process equipment using plasma to which RF power is connected.

The RF power supply provides a process equipment using plasma that supplies RF power in a pulse waveform.

In another aspect, the present invention provides a process equipment using the plasma, comprising: placing a substrate on a susceptor; Injecting process gas from the first injection port to perform a process on the substrate; It provides a substrate processing method comprising the step of exhausting the exhaust gas to the first exhaust port.

And a first step of placing the substrate on the susceptor; A second step of injecting a process gas from the first injection port to exhaust the first gas to the first exhaust port and performing a process on the substrate; And a third step of injecting process gas from the second injection port to exhaust the second exhaust port and performing a process on the substrate.

After the third step, there is provided a method of treating a substrate in which the second step and the third step are sequentially repeated again.

The performing of the process on the substrate provides a method of treating a substrate using a continuous plasma generated by applying continuous RF power to a process gas.

The performing of the process on the substrate provides a method of treating a substrate using a pulsed plasma generated by supplying RF power of a pulse waveform to a process gas.

Hereinafter, with reference to the drawings will be described a preferred embodiment of the present invention; In addition, the embodiment of the present invention relates to a PECVD equipment or an etcher (Etcher) for performing a process for a substrate by injecting the process gas into the plasma state after the injection of the process gas in the chamber as well as LCD manufacturing equipment as well as semiconductor manufacturing equipment It can be. Therefore, the substrate mentioned below includes not only a glass substrate but also a semiconductor wafer, and for the convenience of description, the following description will be made using PECVD equipment as an example.

Embodiment of the present invention basically relates to the equipment for injecting the process gas from the injection port of the chamber side wall to perform the process, and exhaust gas to the exhaust port of the opposite side wall, which will be described later to solve the expected process unevenness Various ways are suggested.

1. First embodiment

FIG. 3 illustrates a configuration of a PECVD apparatus according to a first embodiment of the present invention, wherein the injection port and the exhaust port are symmetrically configured, and specifically, a chamber for forming a constant reaction space therein. 100, a susceptor 110 positioned inside the chamber 100 and having a substrate 200 disposed thereon, a plasma electrode 140 positioned above the susceptor 110, and An RF power source 150 connected to the plasma electrode 140 to apply RF power to the chamber 100, and an edge of the substrate 200 positioned on the inner wall of the chamber 100 and placed in the susceptor 110. The edge frame 120 to be compressed, the first injection port 132 formed on one sidewall of the chamber 100, the second exhaust port 164 positioned below the first injection port 132, and the The second injection port 134 is formed on the opposite sidewall of the first injection port 132, and located below the second injection port 134 Claim 1 includes an exhaust port 162.

The edge frame 120 is preferably fixed to the inner wall of the chamber 100. This is because the process gas injected through the first and second injection ports 132 and 134 leaks into the lower space of the susceptor 110. To prevent the process gas. However, the present invention is not limited thereto, and the edge frame 120 may be configured to rise while pressing the edge of the substrate 200 as in the conventional method.

In the case where the edge frame 120 is fixedly installed, a stepped portion 112 is formed at the edge of the susceptor 110 to prevent leakage, so that when the susceptor 110 is raised, the edge frame 120 is formed. Preferably, the lower surface and the stepped portion 112 are in contact with each other. In order to maintain more airtight, it is preferable to form a sealing on the lower surface of the edge frame 120, and as a sealing means, an O-ring or the like can be expected.

4 schematically illustrates a plasma electrode 140 in which a heater 170 is embedded. Conventional equipment typically includes a heater only in the susceptor 110, thereby heating the substrate 200 only at the bottom thereof. Thus, the heater 170 embedded in the plasma electrode 140 located above the substrate 200. This is because it is possible to further improve the process speed and the process uniformity by allowing the preheating to be carried out through. Although the drawing shows that the heater 170 is built in the plasma electrode 140, the present invention is not limited thereto and may be attached to the outer surface.

In FIG. 3, although the second exhaust port 164 and the first exhaust port 162 are positioned below the first injection port 132 and the second injection port 134, the present invention is not limited thereto. The up and down positions of the furnace injection ports 132 and 134 and the exhaust ports 162 and 164 may vary. However, even in this case, the injection ports 132 and 134 and the exhaust ports 162 and 164 are preferably formed in the same shape at positions symmetric to each other.

The first and second injection ports 132 and 134 may have a rectangular long slit in the side wall of the chamber 100 as shown in FIG. 5, which shows a cross section taken along line AA of FIG. 3, or as shown in FIG. 6. It may be formed, the horizontal length of each injection port 132, 134 should be longer than the side of the adjacent substrate 200, so that the process gas is sprayed to cover the entire substrate 200, whatever the shape .

The shapes of the exhaust ports 162 and 164 may also be formed as rectangular slits or a plurality of exhaust holes as shown in FIG. 5 or FIG. 6. In the drawing, the exhaust ports 162 and 164 and the injection ports 132 and 134 are shown in the same shape, but the first injection port 132 and the second injection port 134 are symmetrically formed with each other, and the first Since the exhaust port 162 and the second exhaust port 164 may be formed symmetrically with each other, the shapes of the exhaust ports 162 and 164 and the injection ports 132 and 134 are not necessarily the same.

The first and second injection ports 132 and 134 are connected to a gas supply unit (not shown) outside the chamber 100. Each injection port may be connected to the same gas supply unit or may be connected to a separately installed gas supply unit, respectively. It is preferable to install a flow control device (not shown) between the ports 132 and 134 and the gas supply unit to control the gas flow rates supplied from both injection ports 132 and 134 to be the same.

The first and second exhaust ports 162 and 164 are also connected to an exhaust pump (not shown) outside the chamber 100. Since the exhaust flow rates of the exhaust ports 162 and 164 need to be the same, each exhaust port 162 and 164 is exhausted. It is preferable to provide a pump (not shown) to precisely control the flow rate of the gas passing through each of the exhaust ports 162 and 164.

The reason why the injection ports 132 and 134 and the exhaust ports 162 and 164 are formed symmetrically is as follows.

The process gas injected from the first injection port 132 is excited as active species near the first injection port 132 by the applied RF power, and is deposited on the substrate 200 while the first exhaust port 162 is applied. Since it flows toward, the further away from the first injection port 132, the active species is reduced by the contribution to the process.

Therefore, when the process gas is injected from the first injection port 132, the thickness of the thin film deposited on the substrate 200 becomes thinner linearly as the distance from the first injection port 132 increases, which causes the second injection port ( The same applies to the case of spraying the process gas in 134).

That is, the thin film thickness and the distance from the injection port are inversely proportional to each other as shown in FIG. 7, wherein Y ₁ illustrates the thickness of the thin film deposited on the substrate 200 when gas is injected from the second injection port 134. , Y ₂ illustrates the thickness of the thin film deposited on the substrate 200 when the gas is injected from the first injection port 132.

Assuming that the distance from the second injection port 134 is X, and the relationship between the thin film thicknesses Y ₁ , Y ₂ and X is expressed by the equation,

Y ₁ = (Y _min -Y _max ) * X / L + Y _max

Y ₂ = (Y _max -Y _min ) * X / L + Y _min

Therefore, after injecting the process gas from the first injection port 132, if the same flow rate is injected from the second injection port 134 on the opposite side for the same time, the thickness of the thin film finally deposited on the substrate 200 is same.

Y = Y ₁ + Y ₂ = Y _max + Y _min = constant

That is, when alternately spraying process gases of the same flow rate through the symmetrical injection ports 132 and 134 for the same time, it becomes possible to form a uniform thin film on the entire substrate 200.

2. Second Embodiment

8 shows a second embodiment of the present invention, and can be applied regardless of whether the injection port is symmetrical. Compared to FIG. 3 illustrating the case of the first embodiment, the remaining portions except for the plasma electrodes 142, 144, 146 and 148 to which RF power is applied and the RF power sources 152, 154, 156 and 158 are the same. Only the parts are explained.

The plasma electrode located on the upper surface of the chamber 100 is divided into first, second, third, and fourth electrode blocks 142, 144, 146, and 148, and the first, second, third, and fourth RF powers are applied to the electrode blocks 142, 144, 146, and 148. 152, 154, 156, and 158 are each connected.

By dividing the plasma electrode into a plurality of electrode blocks 142, 144, 146, and 148 as described above, the variation of RF power according to the position due to the standing wave is minimized, thereby improving process uniformity on a large-area substrate. do. On the other hand, when the plasma electrode is divided into a plurality of electrode blocks as described above, RF power may be applied to each electrode block at the same time, depending on the process may be applied sequentially. In addition, in the drawing, RF power is applied to each plasma electrode. However, the present invention is not limited thereto, and a plurality of electrode blocks may be connected to one RF power source.

FIG. 9 illustrates the planes of the divided first, second, third and fourth plasma electrodes 142, 144, 146, and 148, showing four rectangular electrode blocks. As a matter of course, the plasma electrodes may not be divided in the vertical direction but divided in the horizontal direction.

3. Third embodiment

The third embodiment of the present invention proposes a method of applying RF power applied to the plasma electrodes 140, 142, 144, 146, and 148 in the form of a pulse wave. Such a pulse wave can be realized by turning on / off an RF power source connected to the plasma electrode at regular intervals or by connecting a separate pulse wave generator, and thus, the RF power source 150, 152, 154, 156, and 158 supplying the pulse wave. Detailed description thereof will be omitted.

The reason for using the pulse wave is that when the process gas is injected from the injection ports 132 and 134 of the side wall of the chamber 100 and continuous RF power is applied as in the present invention, the process gas is excited as the active species as soon as it is injected to the substrate. Since the deposition or etching process is performed, a non-uniform phenomenon in which the thin film thickness is closer to the injection ports 132 and 134 and becomes thinner linearly toward the exhaust ports 162 and 164 appears in the deposition process. It is for.

For convenience of explanation, it is assumed that the ionization rate or dissociation rate of the process gas excited by the RF power to the active species is 100%, and if the RF power is continuously supplied, the process gas is immediately injected from the injection ports 132 and 134. Since the transition to the active species is performed on the substrate, and the remaining active species flow to the exhaust ports 162 and 164 continuously, the density of the active species decreases toward the exhaust ports 162 and 164.

The difference in density of the active species results in a linear decrease in the process rate for the substrate from the injection ports 132 and 134 to the exhaust ports 162 and 164.

However, when the pulsed RF power is applied, the plasma is repeatedly generated and disappeared at a predetermined cycle. When the plasma is generated, a process such as deposition or etching is performed by active species, and the process is performed when the plasma is extinguished. It is stopped and only the flow of process gas exists.

As a reference to one point on the substrate 200, when the plasma is extinguished, the process gas is not introduced into the active species from the injection ports 132 and 134, so that the density of the process gas can be uniformly formed. do.

In other terms, if RF power is applied after a large amount of flow to the opposite exhaust port for a predetermined time, instead of exciting the active gas immediately after the process gas is injected, the process gas is uniformly injected into the chamber 100. Since it is excited as an active species, it becomes possible to greatly improve the process nonuniformity by continuous plasma.

As such, when the pulsed plasma is used, the symmetrical injection ports 132 and 134 are not formed on the sidewalls of the chamber 100 as shown in the first embodiment of the present invention. There is an advantage that the uniformity can be sufficiently secured.

Referring to FIG. 3, a process of performing a process for the substrate 200 in such a PECVD apparatus will be described below. In this case, an edge frame 120 is fixedly installed on the inner wall of the chamber 100, and an O-ring 122 is formed on the bottom surface of the edge frame 120, for example.

First, the substrate 200 is loaded and placed on the upper surface of the susceptor 110, and then the susceptor 110 is raised to the process position. At this time, as shown in FIG. 10, the stepped portion 112 of the edge of the susceptor 110 contacts the lower surface of the edge frame 120, and the edge frame 120 compresses the edge of the substrate placed on the upper surface of the susceptor 110. The susceptor 110 stops. Thus, a closed reaction space surrounded by the ceiling and sidewalls of the chamber 100 and the susceptor 110 is formed. Since the process gas injected into the chamber 100 flows only in the reaction space, the gas consumption can be significantly reduced compared to the conventional method.

Next, the first injection port 132 and the first exhaust port 162 are opened, and the process gas is injected into the chamber 100 from the first injection port 132 and discharged to the first exhaust port 162 on the opposite side. To be. In this process, RF power is applied through the plasma electrode 150 to excite the process gas as the active species, and the active species performs the deposition process on the substrate 200.

Next, the first injection port 132 and the first exhaust port 162 are closed, and the second injection port 134 and the second exhaust port 164 are opened to process the process gas from the second injection port 134. When the second injection into the deposition process is performed, a thin film having a uniform thickness can be formed on the entire substrate as described above. Of course, at this time, the gas flow rate and the injection time that are injected from the first injection port 132 and the second injection port 134 should be the same, and the exhaust gas is discharged through the first exhaust port 162 and the second exhaust port 164. The flow rate should also be the same.

As described above, the process of alternately spraying the process gas through the first and second injection ports 132 and 134 may be performed only once, and the process may be repeated several times to several tens of times. It will increase.

Since the deposition process is performed only in the sealed space above the susceptor 110, unnecessary deposition does not occur on the side surface of the susceptor 110 or the lower sidewall of the chamber 100. Even when in-situ cleaning, there is an effect that can greatly save the cleaning gas.

On the other hand, when the plurality of electrode blocks 142, 144, 146, 148 and a plurality of RF power source (152, 154, 156, 158) as shown in FIG. 8, each RF power is applied to each electrode block at the same time or sequentially applied with a time difference If the RF power is applied as a pulse wave, as described above, the uniformity of the process gas may be improved to greatly improve the uniformity of the entire process.

Meanwhile, the case in which the deposition process is performed on the substrate 200 using the PECVD apparatus has been described. However, the present invention may be applied to other processes using plasma, such as etching.

According to the present invention, it is possible to eliminate expensive showerheads and to minimize the space in which gas is supplied, thereby improving vacuum uniformity on the surface of the substrate located inside the chamber, as well as saving process gas or cleaning gas. Cost reduction and productivity improvement can be achieved.

In addition, according to the present invention, it is possible to improve the uniformity of the process by improving the uniformity of the process gas supplied into the chamber.

1 is a schematic configuration diagram of a conventional PECVD equipment

2 is a block diagram showing a state in which the substrate is loaded to the process position in the conventional PECVD equipment

3 is a block diagram of a PECVD apparatus according to a first embodiment of the present invention

4 is a cross-sectional view of a plasma electrode with a heater built therein;

5 is a cross-sectional view taken along the line A-A of FIG.

6 is a configuration diagram in which the injection port and the exhaust port of FIG. 5 are formed differently;

7 is a graph showing the thickness of a thin film deposited on a substrate.

8 is a block diagram of a PECVD apparatus according to a second embodiment of the present invention

9 is a plan view of a plasma electrode according to a second embodiment of the present invention;

10 is a configuration diagram showing a state in which the substrate is loaded to the process position in the PECVD apparatus according to the first embodiment of the present invention

* Description of the symbols for the main parts of the drawings *

100 chamber 110 susceptor

112: stepped portion 120: edge frame

122: O-ring 132: first injection port

134: second injection port 140: plasma electrode

142, 144, 146, and 148: first, second, third and fourth electrode blocks

150: RF power source 152, 154, 156, 158: 1st, 2, 3, 4 RF power source

162: first exhaust port 164: second exhaust port

170: heater 200: substrate

Claims (15)

A chamber forming a constant reaction space therein: A first injection port formed on one sidewall of the chamber and injecting a process gas; A first exhaust port formed on a side wall facing the injection port and discharging exhaust gas; A susceptor positioned inside the chamber and for placing a substrate on an upper surface thereof; Plasma electrode located on the susceptor and connected to the RF power supply for supplying RF power Process equipment using a plasma containing The method of claim 1, A second exhaust port is formed on the side wall where the first injection port is formed, the process equipment using the plasma is formed on the side wall where the first exhaust port is formed The method of claim 2, The first injection port and the second injection port is a process equipment using a plasma having a rectangular slit shape The method of claim 2, The first injection port and the second injection port is a process equipment using a plasma formed by a plurality of injection holes The method of claim 2, The first exhaust port and the second exhaust port is a process equipment using a plasma formed by a plurality of exhaust holes The method of claim 1, An inner edge of the chamber is provided with an edge frame for pressing the edge of the substrate placed in the susceptor, the lower surface of the edge frame is a process equipment using a plasma (sealing) is formed to prevent the leakage of process gas The method of claim 1, At least one of the susceptor or the plasma electrode processing equipment using the plasma is formed a heater for preheating the substrate The method of claim 1, The plasma electrode is a process equipment using a plasma composed of a plurality of electrode blocks The method of claim 8, RF equipment is connected to each of the plurality of electrode block processing equipment using a plasma The method according to claim 1 or 9, The RF power supply is a process equipment using plasma that supplies RF power in a pulse waveform. In the process equipment using the plasma of claim 1, Placing a substrate on the susceptor; Injecting process gas from the first injection port to perform a process on the substrate; Exhausting the exhaust gas to the first exhaust port; Processing method of a substrate comprising In the process equipment using the plasma of claim 2, A first step of placing the substrate on the susceptor; A second step of injecting a process gas from the first injection port to exhaust the first gas to the first exhaust port and performing a process on the substrate; A third step of injecting process gas from the second injection port to exhaust the second exhaust port and performing a process on the substrate; Processing method of a substrate comprising The method of claim 12, After the third step, the substrate processing method of sequentially repeating the second step and the third step again The method according to any one of claims 11 to 13, In the performing of the process on the substrate, a method of treating a substrate using continuous plasma generated by applying continuous RF power to a process gas. The method according to any one of claims 11 to 13, In the performing of the process on the substrate, a method of treating a substrate using pulsed plasma generated by supplying RF power of a pulse waveform to a process gas.