JPS63297566A - Plasma treatment apparatus - Google Patents

Abstract

PURPOSE:To reduce the damage of a substrate to be treated, by introducing a first gas in plasmic state into a reaction chamber and by forming a second gas into plasmic state by means of the above-mentioned gas in plasmic state so as to reduce grain development due to the polymerization of a reactant gas. CONSTITUTION:A first gas is introduced from a gas-introducing passage 7 and a second gas is introduced from a reactant gas-introducing passage 8 into a reaction chamber 1. At this time, a high-frequency voltage is impressed from a high-frequency electric power source 9b on an electrode pair 9a to form the first gas into plasmic state, and, by means of this gas in plasmic state, the second gas (reactant gas) is formed into plasmic state. A bias voltage is impressed from a bias electric power source 5 on a stand 3 for draw in the reactant gas in plasmic state, and, while shifting the stand 3, a CVD film is formed on a substrate 2 to be treated. By this method, plasma having uniform energy and high ion temp. can be formed, and the treatment of film formation, etc., can be uniformly carried out.

Description

Detailed Description of the Invention [Object of the Invention] (Industrial Application Field) The present invention relates to a plasma processing apparatus, and in particular to a plasma processing apparatus suitable for a plasma cvoV apparatus that forms a CVD film on a substrate to be processed. Regarding.

(Prior Art) Plasma processing apparatuses are generally used as CVD apparatuses, ashing apparatuses, etching apparatuses, etc. in the manufacturing process of semiconductor devices.

Among such plasma processing apparatuses, for example, plasma C
VI) In the apparatus, the inside of the reaction chamber is kept at a predetermined degree of vacuum,
A high frequency voltage such as 13.56 HIIZ is applied between the mounting table which holds the substrate to be processed 3 placed in the reaction chamber and an electrode placed opposite to this mounting table. A predetermined reaction gas is passed between the substrate and the substrate to be processed at a predetermined flow rate.

Then, the reactive gas is turned into plasma by the discharge generated between the mounting table and the electrode, and a predetermined CVDWA is applied onto the substrate to be processed.
form.

(Problems to be Solved by the Invention) However, in the conventional plasma processing apparatus described above, for example, when the substrate to be processed becomes large and the mounting table and the electrode facing the mounting table become large, the mounting table and the electrodes facing the mounting table become large. It becomes difficult to cause a discharge between the electrode and the electrode.

Therefore, it was necessary to lower the frequency of the voltage applied between the mounting table and the 7fi pole, or to increase the spatial degree (lower the pressure) in the reaction chamber 17.

Therefore, the kinetic energy of the generated plasma is 1! The problem is that when the temperature is high and the temperature is low, gas molecules that turn into plasma collide with the substrate to be processed, causing damage to the substrate.
There is a problem in that the decomposed reaction gas polymerizes and becomes particulate and adheres to the substrate to be processed, resulting in defects.

The present invention has been made in order to cope with the above-mentioned conventional circumstances, and is capable of reducing the generation of particles due to polymerization of a reaction gas compared to the conventional method, and at the same time, it is possible to reduce the generation of particles caused by the collision of plasma gas molecules. The present invention aims to provide a plasma processing apparatus that can reduce damage to processed substrates.

[Structure of the Invention] (Means for Solving the Problems) That is, the present invention includes a reaction chamber that accommodates a substrate to be processed, and a first gas that is turned into plasma by discharge using an alternating current voltage and is introduced into the reaction chamber. a first gas introduction means for introducing a second gas into the reaction chamber; and a second gas introduction means for introducing a second gas into the reaction chamber. Converts the gas into plasma and converts it into plasma.
1. The method is characterized in that a predetermined treatment is performed on the treated root.

(Function) In the plasma processing apparatus of the present invention, the first gas converting means introduces the first gas which has been turned into plasma by the radiation 111 using the AC voltage into the reaction chamber, and the second gas introducing means introduces the first gas into the reaction chamber. The second gas introduced into the reaction chamber I7 is turned into plasma by the first gas, and a predetermined treatment is applied to the plate to be treated.

Therefore, even if the substrate to be processed is large, the discharge area of the discharge caused by the alternating current voltage can be made small. Therefore, it is possible to generate a discharge with an alternating current voltage of a higher frequency than before, and it is possible to generate a high-quality plasma with low kinetic energy, uniformity, and high temperature. Damage to the substrate to be processed due to molecular collisions can be reduced. Further, since discharge can be caused at a low degree of vacuum (high pressure), the number of particles generated by polymerization of the decomposed reaction gas can be reduced.

(Example) The following is an example in which the present invention is applied to a plasma CVD apparatus.
This will be explained with reference to FIGS. 1 and 2.

A mounting table 3 is disposed within the reaction chamber 1 on which a large substrate 2 to be processed, such as a glass substrate for configuring an active matrix liquid crystal display device, is placed. This mounting table 3 is equipped with a drive device 4 consisting of, for example, a rail 4a and a motor 4b, and is configured to be movable in the direction of the arrow in the figure. Further, this mounting table 3 is connected to a bias power source 5 for drawing ions d3, and a heater 6 for heating the substrate 2 to be processed is arranged inside the mounting table 3.

Further, on the upper part of the mounting table 3, there is provided a gas introduction passage 7 which forms an elongated slit-shaped opening 7a, and this gas introduction passage 7, which is spaced from the mounting table 3 by, for example, several millimeters to several centimeters. A reaction gas passageway 8 is arranged to form a groove 11 part 8a so as to sandwich the opening 7, and to supply a reaction gas into the gas introduced from the opening 7a. The width of the frontage portion 7a and the opening portion 88 in the longitudinal direction thereof is approximately equal to the width of the substrate 2 to be processed.

The gas passageway 7 includes, for example, a pair of elongated strip-shaped electrodes 9a arranged across the gas introduction passageway 7, and a high-frequency power source 9 that supplies a high-frequency voltage to these electrode pairs 9a.
b. Discharge generating means consisting of a capacitor 9C for removing DC components is arranged.

Note that an exhaust pipe 10 connected to an exhaust device (not shown) is connected to the lower part of the reaction chamber 1 and the like.

In plasma CVD of this embodiment with the above configuration, Daisei's substrate 2 to be processed, such as glass B, 41 for configuring an active matrix liquid crystal display device, is placed on the mounting table 3, and the heater 6. Heat.

In addition, the exhaust pipe 10 supplies υ1 air to bring the inside of the reaction chamber 1 to a predetermined degree of vacuum, for example, about 10-1 to 10' orr.
12, Nfl+, N2, etc., from the reaction gas introduction path 8, for example, S! A predetermined reaction gas such as Hs is introduced. At this time, a high frequency voltage of, for example, 100 MHz is applied from the high frequency power source 9b to the electrode pair 9a, and the Ar
, 2, N113, N2, etc. are activated (made into plasma), and a predetermined reaction gas such as 5i114 is activated by this viscous gas.

Then, for example, 10Kl is transferred from the bias voltage m5 to the mounting table 3.
Apply a bias voltage such as ll~13.56H1lZ to draw in the activated reaction gas, and move the mounting table 3 in the direction of the arrow shown by the drive device 4. At the same time, CVDIFu is formed on the substrate 2 to be processed.

That is, in the plasma processing apparatus of this embodiment, since a C discharge is generated between the pair of elongated strip-shaped electrodes 9a having a small discharge area, a high frequency voltage of, for example, 100 Htlz and a voltage of, for example, 10-1 to 10'''rorr are applied. Discharge can be caused in a low degree of vacuum (low pressure).

Therefore, plasma with uniform energy and high ion temperature can be formed, and generation of particles due to polymerization of the decomposed reaction gas can be reduced, so damage to the substrate 2 to be processed can be reduced. At the same time, it is possible to form a high quality CVD film.

Further, the open 1'' portion 7a and the open 1'' portion 8a of the substrate to be processed 2 are provided.
Since film formation is performed without moving the target substrate 2
Even if the film is large, a uniform CVD film can be formed.

[Effects of the Invention 1 As described above, the plasma processing apparatus of the present invention achieves 1. First, by separating the plasma excitation gas and the reaction gas and restricting the plasma reaction to the vicinity of the film forming surface as much as possible compared to the conventional method, it is possible to reduce the generation of particles due to polymerization of the reaction gas, and Damage to the substrate to be processed due to collisions of plasma gas molecules can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a front view showing a plasma processing apparatus according to an embodiment of the present invention, and FIG. 2 is a side view of FIG. 1. 1...Reaction chamber, 2...Here f!
I'1 substrate, 3... mounting table, 4... drive device, 7... gas introduction path, 8... reaction gas introduction path, 9a. ...Electrode pair, 9b...
...High frequency power supply, 9C...Condenser υ. Applicant Tokyo Electron Co., Ltd. Agent Patent Attorney Sasa Suyama - Figure 1

Claims (2)

[Claims] (1) A reaction chamber that accommodates a substrate to be processed, a first gas introduction means that introduces a first gas that has been turned into plasma by discharge using an AC voltage into the reaction chamber, and a second gas that introduces a second gas into the reaction chamber. and a second gas introduction means for converting the second gas into plasma using the plasma-formed first gas to perform a predetermined process on the substrate to be processed. . (2) A predetermined process is performed on the entire surface of the substrate while relatively moving the substrate and the openings in the reaction chamber of the first gas introduction means and the second gas introduction means. A plasma processing apparatus according to claim 1.