KR101321331B1 - The system for depositing the thin layer - Google Patents

Abstract

PURPOSE: A system for depositing a thin film for a solar cell is provided to reduce processing time by automatically exchanging wafers between a deposition cassette and a general cassette. CONSTITUTION: A thin film deposition part performs a deposition process. A cassette transfer part (300) supplies a cassette to the thin film deposition part. A cassette changing part (400) is installed in front of a cassette loading transfer part. The cassette changing part moves the wafer of a deposition cassette to a general cassette. A cassette conveyer part (500) successively supplies and discharges the cassette.

Description

Thin Film Deposition System for Solar Cells {THE SYSTEM FOR DEPOSITING THE THIN LAYER}

The present invention relates to a thin film deposition system for a solar cell, and more particularly, in a solar cell device manufacturing process, a wafer is automatically moved from a general-purpose cassette having a general wafer spacing to a deposition cassette having a narrow spacing, The present invention relates to a thin film deposition system for a solar cell capable of continuously performing a thin film deposition process on a cassette.

In general, a semiconductor device or a flat panel display device is subjected to various manufacturing processes, and among these, a process of depositing a predetermined thin film on a wafer or a glass (hereinafter, referred to as a substrate) is essential. The thin film deposition process is mainly performed by sputtering, chemical vapor deposition (CVD), or atomic layer deposition (ALD).

First, the sputtering method injects an inert gas such as argon into the process chamber while applying a high voltage to the target to generate argon ions in a plasma state. At this time, argon ions are sputtered on the surface of the target, and atoms of the target are separated from the surface of the target and deposited on the substrate.

Although a high purity thin film having excellent adhesion with a substrate can be formed by such a sputtering method, when a highly integrated thin film having a process difference is deposited by a sputtering method, it is very difficult to ensure uniformity over the entire thin film. There is a limit to the application of

Next, chemical vapor deposition (CVD) is the most widely used deposition technique, in which a thin film having a desired thickness is deposited on a substrate using a reaction gas and a decomposition gas. For example, the chemical vapor deposition method first deposits a thin film having a desired thickness on a substrate by injecting various gases into a reaction chamber and chemically reacting gases induced by high energy such as heat, light or plasma.

In addition, the chemical vapor deposition method increases the deposition rate by controlling the reaction conditions through the ratio and amount of the plasma or gases applied as the reaction energy.

However, in the chemical vapor deposition method, since the reactions are rapid, it is very difficult to control the thermodynamic stability of the atoms, and the physical, chemical and electrical characteristics of the thin film are deteriorated.

Finally, atomic layer deposition is a method for depositing atomic layer unit thin films by supplying source gas (reaction gas) and purge gas alternately. The thin film formed thereby has a high aspect ratio, is uniform even at low pressure, and has electrical and physical characteristics. great.

In recent years, chemical vapor deposition is difficult to apply to the structure having a very high aspect ratio due to the limitation of step coverage. Therefore, in order to overcome the limitation of the step coverage, an atomic layer deposition method using surface reaction has been used. Is being applied.

The atomic layer deposition apparatus which performs the atomic layer deposition method includes a batch type apparatus which processes a plurality of substrates in a batch, and a sheet type type apparatus which processes a process by loading substrates one by one in a process chamber. However, the conventional atomic layer deposition apparatus is complicated because the transfer means for transferring the cassette must be provided in each chamber. In order to overcome this problem, there is a case where the cassette is directly brought into the process chamber by using a transport robot instead of having a separate transport device inside the chamber. However, the transport robot is expensive, difficult to control, and a process tag according to the carrying out of the cassette. There is a problem that the time is increased.

The technical problem to be solved by the present invention is to automatically move the wafer from the general-purpose cassette having a common wafer interval in the manufacturing process of the solar cell device to the deposition cassette having a dense gap, and continuously depositing thin films for a plurality of deposition cassettes It is to provide a thin film deposition system for solar cells that can proceed the process.

According to an aspect of the present invention, there is provided a thin film deposition system for a solar cell, the thin film deposition unit performing a thin film deposition process in a state where a plurality of wafers are mounted in a plurality of deposition cassettes; A cassette stack transfer unit installed adjacent to the thin film deposition unit and having a plurality of deposition cassettes stacked and horizontally moved; A cassette conveying unit which supplies a cassette to the cassette stacking conveying unit and discharges the cassette of the thin film depositing unit to the cassette stacking conveying unit; A cassette changer installed at the front of the cassette stack transfer unit and configured to transfer a wafer of a universal cassette to the deposition cassette and to transfer a wafer of the deposition cassette to the universal cassette; And a cassette conveyor unit installed at the front of the changing unit, continuously supplying the cassette to which the thin film deposition process is to be performed, and continuously discharging the cassette having the thin film deposition process completed.

In addition, in the thin film deposition system for a solar cell of the present invention, the thin film deposition unit is preferably installed side by side two thin film deposition apparatus spaced apart at regular intervals.

The cassette stack transfer unit is preferably disposed in a space between the two thin film deposition apparatuses.

In addition, the cassette stack transfer unit is preferably composed of two discharge transfer line for discharge and two transfer transfer line for supply.

In addition, it is preferable that two pitch change devices are disposed at regular intervals so as to correspond to each of the thin film deposition apparatuses.

The cassette conveyor unit may further include a supply line for continuously supplying a general-purpose cassette to which the thin film deposition process is to be performed to the cassette changing unit, and a discharge line which is installed below the supply line and continuously discharges the general-purpose cassette having the thin film deposition process completed. It is preferable to include.

According to the thin film deposition system for solar cells of the present invention, the wafer exchange is automatically performed between the deposition cassette and the general purpose cassette for loading wafers at dense intervals for an efficient thin film deposition process, and are very fast in the automatic production line of solar cell devices. There is an advantage in that the thin film deposition process can be continuously performed on a large amount of wafers within the processing time.

1 is a block diagram showing the structure of a thin film deposition system for a solar cell according to an embodiment of the present invention.
2 is a view showing the structure of a thin film deposition unit according to an embodiment of the present invention.
3 is a plan view illustrating a structure of an opening and closing foldable part according to an exemplary embodiment of the present invention.
4 is a view showing the structure of the first connecting means according to an embodiment of the present invention.
5 is a diagram showing the structure of a cassette according to an embodiment of the present invention.
6 is a side view illustrating a structure of a cassette conveyor unit according to an embodiment of the present invention.

Hereinafter, a specific embodiment of the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIG. 1, the thin film deposition system 1 for a solar cell according to the present embodiment includes a thin film deposition unit 100, a cassette stack transfer unit 200, a cassette transfer unit 300, a cassette change unit 400, and a cassette. It is configured to include a conveyor 500.

First, the thin film deposition unit 100 is a component that performs a thin film deposition process in a state where a plurality of wafers are mounted in a plurality of deposition cassettes. As shown in FIG. 2, the thin film deposition unit 100 includes an external chamber 110, a process chamber 120, and an opening / closing loading unit 130. In the thin film deposition system for a solar cell according to the present embodiment, as shown in FIG. 1, two thin film deposition units 100 may be provided side by side at a predetermined interval so that the overall process time may be shortened.

First, the outer chamber 110 has openings 112 formed at both sides thereof, and a plurality of process chambers 120 are embedded therein, and openings 122 are formed at both sides thereof so that the cassette C may be carried in or taken out. One of the openings 112 and 122 is used as the carrying path of the cassette and the other is used as the carrying out path of the cassette. Therefore, the two openings are preferably formed to be symmetrical in the direction facing each other.

The process chamber 120 accommodates a cassette C on which a substrate is loaded and performs a thin film deposition process on the substrate, for example, an atomic layer deposition process, so that the cassette C can be carried in or taken out. Openings 122 are formed on both sides, respectively. The opening 122 formed in the process chamber 120 is formed at a position corresponding to the position of the opening 112 formed in the outer chamber 110. 140).

Next, as shown in FIG. 2, the opening / closing carrying part 130 carries a cassette into the process chamber 120, and one opening 122 and the outer chamber 110 of the process chamber 120 are disposed. One side of the opening 112 is a component for opening and closing at the same time. That is, the opening / closing carrying part 130 opens and closes the outer chamber 110 and the process chamber 120 in the state opened by the openings 112 and 122, and simultaneously draws the cassette to which the thin film deposition process is to be performed. A component that performs a function of bringing into the process chamber 120.

To this end, in this embodiment, the opening and closing portion 130 is specifically shown in Figures 2 and 3, the first inner door 131, the first outer door 132, the first connecting means 133 and It may be configured to include a first moving means (134). First, the first inner door 131 is a door that opens and closes one side opening 122 of the process chamber 130, and the first cassette holder 135 is shown in FIGS. 2 and 3. It is connected to the inner wall of the first inner door 131, and is a component for loading at least one cassette.

In the present embodiment, the first cassette holder 135 is specifically configured as a first cassette, as shown in FIGS. 2 and 4. The first cassette support rod is provided with two rods side by side to support both side edges of the lower surface of the cassette. At this time, the width between the two support rods should be formed slightly narrower than the width of the cassette so that the cassette can be stably supported by the two support rods.

Next, the first outer door 132 is a door that opens and closes an opening of one side of the outer chamber 110, and is connected to the first inner door 131 by a first connecting means 133 described later. do. In this embodiment, the first inner door 131 and the first outer door 132 are elastically connected by the connecting means 133. Therefore, the connecting means 133 may be composed of a conventional flexible pogo pin member. That is, it includes a large diameter portion fixed to the first outer door 132, a small diameter portion fixed to the first inner door 131, and a compression spring for elastically supporting the small diameter portion in the large diameter portion. In addition, a compression spring having a larger modulus of elasticity is further installed on the outer circumference of the pogo pin member. Accordingly, the first inner door 131 and the first outer door 132 may approach or move away from each other, rather than being fixed to each other. In this case, the separation distance between the first inner door 131 and the first outer door 132 is greater than the separation distance between the opening 112 of the outer chamber and the opening 122 of the process chamber (t1> t2).

Next, the first moving means 134 is a component for reciprocating the first inner door 131 and the first cassette holder 135 in a horizontal direction together with the first outer door 132. To this end, the first moving means 134 is a conventional ball screw member, a screw, a nut member reciprocating linearly by the rotation of the screw, a jig connecting the nut member and the second door and the screw It may be composed of a driving source to rotate.

In addition, the first inner door 131 and the first outer door 132 are each provided with a sealing means, the sealing means is a mechanical seal (O-ring) or the like, and other known means Can be applied. Preferably, the sealing means of the first inner door 131 is a mechanical seal, and the sealing means of the first outer door 132 is provided by an O-ring.

Meanwhile, in the present embodiment, gas supply means 40 for supplying source gas and purge gas to the inside of the process chamber 20 through the outer chamber 10 and exhaust means for exhausting the process chamber 20 ( 50) is further provided.

In addition, although not shown, it is preferable that a heater is further provided between the outer chamber 121 and the process chamber 120. This is to maintain a constant internal temperature of the process chamber 120.

5 also shows a cassette C loaded in the process chamber 120. As shown, it can be seen that a plurality of substrates are loaded in a standing (tilted angle at a predetermined angle from vertical or vertical).

Meanwhile, in the thin film deposition unit 100 according to the present embodiment, two or more process chambers 120 are provided in the outer chamber 110 in the vertical direction or the horizontal direction to increase the operating efficiency of the equipment. desirable.

Next, the cassette stack transfer unit 200 is installed adjacent to the thin film deposition unit 100 and is a component in which a plurality of deposition cassettes are stacked and horizontally moved. That is, the cassette stack transfer unit 200 prepares a number of cassettes that can be processed in one process by the thin film deposition unit 100 and sets the cassettes in a standby state, and the process is completed in the thin film deposition unit 100. Receiving a cassette serves to pass the cassette to the changing unit 400 to be described later.

In this embodiment, as shown in FIG. 1, the cassette stack transfer unit 200 is disposed in a space between two thin film deposition units 100 to minimize the movement stroke of the cassette transfer unit 300 which will be described later, and a process time. It is preferable because it can isolate | separate.

In addition, the cassette stack transfer unit 200 includes two discharge transfer line 210 for discharge and two supply transfer line 220 for supply to supply and receive a cassette to each thin film deposition unit 100. It is preferable. Therefore, one discharge load transfer line 210 and the supply load transfer line 220 are divided to correspond to the thin film deposition units 100. At this time, each discharge transfer line 210 is provided with a space in which a plurality of cassettes can be stacked in a row, and has a structure capable of horizontally moving the plurality of cassettes in a specific direction.

Meanwhile, the supply stack transfer line 220 may have a structure substantially the same as that of the stack transport line 210 for discharge, and only the direction of moving the cassette is configured in a direction opposite to the stack transport line 210 for discharge. do.

Next, as shown in FIG. 1, the cassette transfer unit 300 is provided in each thin film deposition unit 100, and supplies a cassette of the cassette stack transfer unit 200 to the thin film deposition unit 100. The cassette discharges the cassette of the thin film deposition unit 100 to the cassette stack transfer unit 200. At this time, the cassette transfer unit 300 has a structure that can be moved horizontally after picking up the cassette placed in the cassette holder of the thin film deposition unit 100, on the contrary, the cassette placed on the supply cassette transfer line 210 Pick up and transfer to the cassette holder. Meanwhile, the cassette transfer unit 300 may move a plurality of cassettes in one process.

Next, as shown in FIG. 1, the cassette changing unit 400 is installed in front of the cassette stack transfer unit 200, and transfers the wafer of the universal cassette C ′ to the deposition cassette C. It is a component which transfers the wafer of the said vapor deposition cassette C to the said universal cassette C '. The thin film deposition unit 100 according to the present embodiment uses a deposition cassette having a narrower gap between substrates than a general purpose cassette in order to increase deposition quality and efficiency. Herein, the general purpose cassette refers to a cassette having a gap between substrates generally used in a solar cell device manufacturing process, and the deposition cassette refers to a unique cassette having a gap between substrates narrower than the universal cassette.

Therefore, the cassette changing unit 400 serves to transfer a plurality of substrates contained in the universal cassette to the deposition cassette or to transfer a plurality of substrates contained in the deposition cassette to the universal cassette. The specific structure of the cassette changing unit 400 may be variously changed.

Next, as shown in FIG. 1, the conveyor unit 500 is installed in front of the cassette changing unit 400, and continuously supplies the cassette to which the thin film deposition process is to be performed to the cassette changing unit 400, and deposits the thin film. It is a component that continuously discharges the cassette after the process is completed. The cassette conveyor unit 500 may employ a conveyor of a distribution line generally used.

However, in the present embodiment, the cassette conveyor unit 500 may have a two-layer structure, as shown in FIG. 6. First, the upper line 510 is composed of a supply line for continuously supplying the cassette for the thin film deposition process to the cassette changing unit 400, and the lower layer 520 is installed below the supply line. It consists of a discharge line which continuously discharges the general-purpose cassette in which the deposition process is completed. A cassette lowering part 530 is provided between the supply line 510 and the discharge line 520 to lower the cassette downward.

Thus, if the cassette conveyor 500 has a two-layer structure, the overall system can reduce the area occupied in the clean room, there is an advantage that can maximize the logistics transport efficiency.

1: thin film deposition system for solar cells according to an embodiment of the present invention
100: thin film deposition unit 200: cassette stack transfer unit
300: cassette transfer unit 400: cassette changing unit
500: cassette conveyor

Claims (6)

A thin film deposition unit for performing a thin film deposition process with a plurality of wafers mounted on a plurality of deposition cassettes;
A cassette stack transfer unit installed adjacent to the thin film deposition unit and having a plurality of deposition cassettes stacked and horizontally moved;
A cassette conveying unit which supplies a cassette to the cassette stacking conveying unit and discharges the cassette of the thin film depositing unit to the cassette stacking conveying unit;
A cassette changer installed at the front of the cassette stack transfer unit and configured to transfer a wafer of a universal cassette to the deposition cassette and to transfer a wafer of the deposition cassette to the universal cassette;
And a cassette conveyor unit installed in front of the cassette changing unit, the cassette conveyor unit continuously supplying the cassette to which the thin film deposition process is to be performed and continuously discharging the cassette having the thin film deposition process completed. The method of claim 1, wherein the thin film deposition unit,
Thin film deposition system for a solar cell, characterized in that two thin film deposition apparatus is installed side by side spaced apart. The method of claim 2, wherein the cassette stack transfer unit,
Thin film deposition system for a solar cell, characterized in that disposed in the space between the two thin film deposition apparatus. The method of claim 3, wherein the cassette stack transfer unit,
A thin film deposition system for a solar cell, comprising two discharge transfer lines for discharge and two supply transfer lines for supply. The method of claim 4, wherein the cassette changing unit,
2. The thin film deposition system for a solar cell of claim 2, wherein two pitch change devices are disposed at regular intervals so as to correspond to the thin film deposition devices. The method of claim 1, wherein the cassette conveyor unit,
A supply line for continuously supplying the cassette for the thin film deposition process to the cassette changing unit,
The solar cell thin film deposition system installed on the lower side of the supply line, characterized in that it comprises a discharge line for continuously discharging the general-purpose cassette is completed.

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