JP5303973B2 - Thin film manufacturing apparatus and thin film manufacturing method - Google Patents

Description

  The present invention relates to a thin film manufacturing apparatus and a thin film manufacturing method, and is particularly suitable when applied to a manufacturing method of a thin film photoelectric conversion element or the like.

  As a method for producing a thin film photoelectric conversion element with high productivity, each layer including a photoelectric conversion layer mainly composed of a-Si is formed on a flexible substrate made of a long polymer material or a metal such as stainless steel. There is a way to do it. Here, as a method of forming a plurality of layers on a long flexible substrate, a roll-to-roll method of forming a film on a flexible substrate moving in each film formation chamber, and a stop in the film formation chamber are used. There is a stepping roll method in which after forming a film on a flexible substrate, the flexible substrate portion after film formation is sent out of the film formation chamber.

In this type of conventional film forming apparatus, the transfer is performed with the flexible substrate surface horizontal, but in order to save the installation space of the apparatus, a method of transferring the substrate with the flexible substrate surface vertical has been proposed. ing. Furthermore, in order to increase the film formation efficiency in one thin film photoelectric conversion element manufacturing apparatus, it is also known that a plurality of flexible substrates are transported in parallel and formed on each flexible substrate surface. Yes.
Here, as a method for efficiently forming a-Si on the flexible substrate surface, there is a method using plasma CVD. In this plasma CVD, a raw material gas is introduced into the chamber while evacuating the chamber, and a high-frequency voltage is applied between the electrodes to generate plasma in the chamber, on the surface of the flexible substrate in the chamber. In addition, an a-Si-based thin film can be formed.

Further, in Patent Document 1, when an undesired reaction product is deposited on the inner wall of the reaction tube facing the susceptor and the reaction product becomes flakes, the expansion / contraction stress due to the difference in thermal expansion coefficient In order to prevent the reaction product from peeling off and contaminating the GaAs substrate, a method is disclosed in which a high-frequency coil is provided around the reaction tube to heat the susceptor by electromagnetic induction.
JP 2004-179210 A

  However, in plasma CVD, when the source gas is exhausted through the exhaust port, it is cooled, and unwanted reaction products adhere to the inner wall of the chamber. When the reaction product attached to the inner wall of the chamber peels off, it falls to the bottom of the chamber and deposits the reaction product, so that the exhaust path of the source gas is disturbed by the reaction product and the surface of the flexible substrate There has been a problem that the film thickness uniformity of the thin film formed thereon deteriorates.

On the other hand, in the method disclosed in Patent Document 1, since the susceptor is heated by electromagnetic induction in order to prevent unwanted reaction products from being deposited on the inner wall of the reaction tube facing the susceptor, a plasma CVD apparatus is used. When applied to the above, there is a problem that high-frequency noise is superimposed on an electrode for generating plasma, and the plasma generated in the chamber becomes unstable.
Therefore, an object of the present invention is to provide a thin film manufacturing apparatus and a thin film manufacturing method capable of reducing reaction products deposited on the bottom of the chamber without adversely affecting the plasma generated in the chamber. .

  In order to solve the above-described problem, according to the thin film manufacturing apparatus of claim 1, a chamber that isolates the interior from the outside, an exhaust port that exhausts the interior of the chamber, and a gas that introduces a source gas into the chamber An introduction pipe, an electrode for generating plasma in the chamber, and a reaction product receiver that is provided on an inner wall or bottom of the exhaust side of the chamber and receives a reaction product separated from the inner wall of the exhaust side of the chamber. It is characterized by that.

  According to the thin film manufacturing method of claim 3, the step of transporting the flexible substrate into a chamber that isolates the interior from the outside, and the introduction of a source gas into the chamber while plasma is introduced into the chamber. The reaction product that is generated and peeled from the inner wall on the exhaust side of the chamber is received by the reaction product receiver provided on the inner wall or bottom of the exhaust side of the chamber, and is formed on the film formation surface of the flexible substrate. And a step of forming a film.

  As described above, according to the present invention, even when the reaction product adhering to the inner wall of the chamber is peeled off during film formation, the reaction product can be received by the reaction product receiver. In addition, when the allowable amount of the reaction product is exceeded, the reaction product can be discharged to the exhaust port. For this reason, even when an undesired reaction product adheres to the inner wall of the chamber because it is cooled when the source gas is exhausted, it is possible to reduce the reaction product that accumulates on the bottom of the chamber, and deposits on the bottom of the chamber Since it is possible to suppress the disturbance of the exhaust path of the source gas by the reaction product, it is possible to improve the film thickness uniformity of the thin film formed on the surface of the flexible substrate It becomes.

Hereinafter, a thin film manufacturing apparatus according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional view showing a schematic configuration of a thin film manufacturing apparatus according to the first embodiment of the present invention.
In FIG. 1, a high voltage electrode 13 and a ground electrode 17 that generate plasma in the chamber 11 are disposed opposite to each other in the chamber 11. The high voltage electrode 13 is connected to a high frequency power source 16 that generates a high frequency voltage. Further, the chamber 11 is provided with an exhaust port 12 for exhausting the inside of the chamber 11 and a gas introduction pipe 15 for introducing a source gas into the chamber 11. The high voltage electrode 13 may be a shower electrode that ejects the source gas introduced through the gas introduction pipe 15 into the chamber 11. The ground electrode 17 has a built-in heater 18 for heating the ground electrode 17. During film formation, the substrate 21 is heated in contact with the ground electrode 17.

  A reaction product receiver 14 is provided on the inner wall of the exhaust side of the chamber 11 to receive the reaction product 22 peeled from the inner wall of the chamber 11 on the exhaust side. Here, the reaction product receiver 14 is preferably provided immediately below a portion where the amount of the reaction product 22 attached is large. For example, the reaction product receiver 14 can be intensively arranged around the exhaust port 12. Moreover, it is preferable that the reaction product receiver 14 is detachably attached to the chamber 11.

Then, when forming a thin film of a-Si based on the surface of the flexible substrate 21, carrying the flexible substrate 21 into the chamber 11. Then, while exhausting the inside of the chamber 11 through the exhaust port 12, the raw material gas is introduced into the chamber 11 through the gas introduction pipe 15, and a high frequency voltage is applied to the high voltage electrode 13. Plasma can be generated between the first electrode and the ground electrode 17 to form an a-Si thin film on the surface of the flexible substrate 21 in the chamber 11. In addition, as the flexible substrate 21, a polyimide film, a polyethylene film, etc. can be used, for example.

  Here, when the inside of the chamber 11 is exhausted through the exhaust port 12, it is cooled when the source gas is exhausted, and an undesired reaction product 22 adheres to the inner wall of the chamber 11. For example, when an a-Si-based thin film is formed on the surface of the flexible substrate 21, silicon powder adheres to the inner wall of the chamber 11 as the reaction product 22. When the reaction product 22 attached to the inner wall of the chamber 11 is peeled off during film formation, the reaction product 22 is accumulated in the reaction product receiver 14, and the reaction product 22 accumulated in the reaction product receiver 14 is formed into a film. Can be discarded at the end. For this reason, the reaction product 22 deposited on the bottom of the chamber 11 can be reduced, and the reaction product 22 deposited on the bottom of the chamber 11 can suppress the disturbance of the exhaust path of the source gas. Therefore, it becomes possible to improve the film thickness uniformity of the thin film formed on the surface of the flexible substrate 21.

FIG. 2 is a cross-sectional view showing a schematic configuration of a thin film manufacturing apparatus according to the second embodiment of the present invention. In addition, the same code | symbol is attached | subjected about the same part as the structure of FIG. 1, and detailed description is abbreviate | omitted.
In FIG. 2, a reaction product receiver 24 that receives the reaction product 22 separated from the inner wall of the exhaust side of the chamber 11 is provided on the bottom surface of the exhaust side of the chamber 11. Here, the reaction product receiver 24 is preferably provided immediately below a portion where the reaction product 22 is attached in a large amount. Moreover, it is preferable that the reaction product receiver 24 is detachably attached to the chamber 11. Further, when the reaction product receiver 24 is attached to the bottom of the chamber 11, a hole through which the route reaction product 22 passes is formed in the bottom of the chamber 11 so as not to hinder the exhaust of the raw material gas, and below the hole. A reaction product receiver 24 can be arranged.

  When the reaction product 22 attached to the inner wall of the chamber 11 is peeled off during film formation, the reaction product 22 is accumulated in the reaction product receiver 24, and the reaction product 22 accumulated in the reaction product receiver 24 is formed into a film. Can be discarded at the end. For this reason, the reaction product 22 deposited on the bottom of the chamber 11 can be reduced, and the reaction product 22 deposited on the bottom of the chamber 11 can suppress the disturbance of the exhaust path of the source gas. Therefore, the film quality of the thin film formed on the surface of the flexible substrate 21 can be improved.

Contact name, although not shown, as the reaction products accepted shape, for example, by shaped like a tulip used in pachinko, induces the reaction product adhering extensively exhaust port be able to.

Then, the reaction product was peeled from the inner wall of the exhaust side of Chang bar, while inducing the exhaust port through the reaction product accepted, it is possible to form a film on the deposition surface of the flexible base plate .
Thus, when it exceeds an allowable amount that can undergo a reaction product in the reaction products accepted, it becomes possible to discharge the reaction product in the exhaust port, and deposited on the bottom of Chang Ba reaction since the exhaust passage of the raw material gas can be suppressed from being disturbed Te to the product, and can improve the film thickness uniformity of the thin film formed on a surface of the flexible base plate Become.

  The thin film manufacturing apparatus of the present invention can be suitably used for a manufacturing method of a thin film photoelectric conversion element such as a-Si, and in particular, a thin film element in which a plurality of layers are formed on a long flexible substrate. It can be widely used in manufacturing methods.

It is sectional drawing which shows schematic structure of the thin film manufacturing apparatus which concerns on 1st Embodiment of this invention. It is sectional drawing which shows schematic structure of the thin film manufacturing apparatus which concerns on 2nd Embodiment of this invention .

Explanation of symbols

11 chamber 12 exhaust port 13 high-voltage electrode 14,24,25 reaction product receiver 15 gas introduction pipe 16 a high frequency power source 17 ground electrode 18 heater 19, 20 support member 21 Allowed FLEXIBLE substrate 22 reaction product

Claims (3)

A thin film manufacturing apparatus for forming a thin film on the surface of a flexible substrate arranged in a vertical direction,
A chamber that isolates the interior from the outside,
An exhaust port that passes through the inner wall of the chamber facing the surface of the flexible substrate disposed in the vertical direction so as to communicate with the interior, and exhausts the interior of the chamber;
A gas introduction pipe for introducing a source gas into the chamber;
An electrode for generating plasma in the chamber;
A thin film manufacturing apparatus comprising: a reaction product receiver provided on an inner wall of the chamber or a bottom portion of the chamber and receiving a reaction product separated from an inner wall on the exhaust side of the chamber. It said reaction product receiving a thin film manufacturing apparatus according to claim 1, characterized in that the reaction product was peeled from the inner wall of the chamber, before Symbol mounted so as to be discharged through the exhaust port. Transporting a flexible substrate disposed vertically in a chamber that isolates the interior from the outside;
While introducing a source gas into the chamber, plasma is generated in the chamber, and a reaction product separated from an inner wall facing the surface of the flexible substrate is provided on the inner wall or bottom of the chamber. And a step of forming a film on the film forming surface of the flexible substrate while receiving the reaction product.

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