JPH0794712B2 - Plasma processing device - Google Patents

Description

The present invention relates to a plasma processing apparatus, and more particularly to a substrate to be processed.
The present invention relates to a plasma processing apparatus suitable for a plasma CVD apparatus that forms a CVD film.

(Prior Art) Generally, a plasma processing apparatus is used as a CVD apparatus, an ashing apparatus, an etching apparatus, or the like in a semiconductor device manufacturing process or the like.

Among such plasma processing apparatus, for example, plasma CV
In the D device, the inside of the reaction chamber is set to a predetermined degree of vacuum, and, for example, 13.56 MHz or the like is placed between the mounting table which is placed in the reaction chamber and holds the substrate to be processed, and the electrode which is arranged facing the mounting table. Is applied, and a predetermined reaction gas is passed at a predetermined flow rate between the electrode and the substrate to be processed.

Then, the reaction gas is turned into plasma by the electric discharge generated between the mounting table and the electrode to form a predetermined CVD film on the substrate to be processed.

(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 electrodes facing the mounting table become large, the mounting table and the electrode It becomes difficult to generate an electric discharge between and.

Therefore, it is necessary to lower the frequency of the voltage applied between the mounting table and the electrodes, or to increase the degree of vacuum in the reaction chamber (lower the pressure).

Therefore, the kinetic energy of the generated plasma is high,
In addition, the temperature becomes low, and the gas molecules turned into plasma collide with the substrate to be processed and damage the substrate to be processed.The decomposed reaction gas is polymerized into particles and adheres to the substrate to be processed, causing defects. There is a problem that it occurs.

The present invention has been made in response to such a conventional situation, and can reduce the generation of particles due to polymerization of a reaction gas as compared with the related art, and can reduce the number of particles to be processed due to collision of gas molecules turned into plasma. An object of the present invention is to provide a plasma processing apparatus capable of reducing damage.

[Structure of the Invention] (Means for Solving Problems) That is, according to the present invention, there is provided a first reaction chamber for accommodating a substrate to be processed, and a first plasma plasma generated by discharge by an AC voltage from the slit-shaped opening into the reaction chamber. First to introduce gas
Gas introduction means, second gas introduction means for introducing a second gas into the reaction chamber from an opening formed so as to sandwich the slit-shaped opening of the first gas introduction means, A substrate and means for relatively moving the slit-shaped opening of the first gas introduction means and the opening of the second gas introduction means, wherein the plasma-converted first gas causes A plasma processing apparatus, wherein the second gas is turned into plasma and a predetermined process is performed on the substrate to be processed.

The invention according to claim 2 is a reaction chamber for accommodating a substrate to be processed, and a first gas for introducing an inert gas, which is turned into plasma by discharge with high-frequency power, into the reaction chamber from a slit-shaped opening. An introducing means; a second gas introducing means for introducing a reaction gas into the reaction chamber from an opening formed so as to sandwich the slit-shaped opening of the first gas introducing means; the substrate to be processed; And a means for relatively moving the slit-shaped opening of the first gas introduction means and the opening of the second gas introduction means, and the reaction gas is made into plasma by the inert gas made into plasma. And a predetermined processing is performed on the substrate to be processed.

The invention according to claim 3 is a reaction chamber for accommodating a substrate to be processed, and a first gas for introducing an inert gas, which is turned into plasma by discharge with high frequency power, into the reaction chamber from a slit-shaped opening. An introducing means, a second gas introducing means for introducing SiH ₄ gas into the reaction chamber from an opening formed so as to sandwich the slit-shaped opening of the first gas introducing means, the substrate to be processed, And a means for relatively moving the slit-shaped opening of the first gas introducing means and the opening of the second gas introducing means, wherein the reactive gas is plasma-converted by the plasmatized inert gas. And a predetermined processing is performed on the substrate to be processed.

(Operation) In the plasma processing apparatus of the present invention, the first gas introducing means converts the first plasma into the plasma by the discharge by the AC voltage.
Gas is introduced into the reaction chamber, and the second gas introduced into the reaction chamber is converted into plasma by the first gas that has been converted into plasma by the second gas introduction means to subject the substrate to be processed to a predetermined process.

Therefore, even if the substrate to be processed is large, the discharge area of the discharge due to the AC voltage can be reduced. Therefore, it is possible to generate a discharge with an AC voltage having a higher frequency than in the conventional case, to generate a high-quality plasma with low kinetic energy and high temperature, and to collide with gas molecules converted into plasma. It is possible to reduce damage to the substrate to be processed due to. Further, since the discharge can be generated at a low degree of vacuum (high pressure), the number of particles generated by the polymerization of the decomposed reaction gas can be reduced.

Further, since the openings of the gas introducing means are arranged close to each other, it is possible to perform the processing efficiently, and by relatively moving the substrate to be processed and the opening, it is possible to uniformly process the large substrate. can do.

(Example) An example in which the present invention is applied to a plasma CVD apparatus will be described below with reference to FIGS. 1 and 2.

In the reaction chamber 1, there is arranged a mounting table 3 on which a large substrate 2 to be processed such as a glass substrate for constituting an active matrix type liquid crystal display device is mounted. The mounting table 3 includes a drive device 4 including, for example, a rail 4a and a motor 4b, and is configured to be movable in the direction of the arrow in the figure. The mounting table 3 is connected to a bias power source 5 for attracting ions, and a heater 6 for heating the substrate 2 to be processed is arranged in the mounting table 3.

In addition, a gas introduction path 7 that forms an elongated slit-shaped opening 7a is provided at an upper portion of the mounting table 3 with respect to the mounting table 3, for example, about several millimeters to several centimeters.
An opening 8a is formed so as to sandwich it, and a reaction gas introduction passage 8 for supplying a reaction gas into the gas introduced from the opening 7a is arranged. In addition, as shown in FIG.
The length of the 7a and the opening 8a in the longitudinal direction is configured to be substantially the same as the width of the substrate 2 to be processed.

In the gas introduction path 7, for example, elongated strip electrode pairs 9a arranged so as to sandwich the gas introduction path 7, a high frequency power supply 9b for supplying a high frequency voltage to these electrode pairs 9a, and a capacitor for removing a direct current component. Discharge generating means such as 9c is arranged.

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 the plasma CVD apparatus of this embodiment having the above-described configuration, a large substrate 2 to be processed, such as a glass substrate for forming an active matrix type liquid crystal display device, is placed on the mounting table 3 and heated by the heater 6.

In addition, the inside of the reaction chamber 1 is evacuated through the exhaust pipe 10 to a predetermined vacuum degree of, for example, about 10 ^-1 to 10 ^-2 Torr, and the gas introduction path 7 is used to evacuate Ar, H ₂ , NH ₃ , N _2, etc. Is introduced, and a predetermined reaction gas such as SiH ₄ is introduced from the reaction gas introduction passage 8. At this time, a high frequency voltage of, for example, 100 MHz is applied from the high frequency power supply 9b to the electrode pair 9a, and the Ar,
Gases such as H ₂ , NH ₃ and N ₂ are activated (converted into plasma), and a predetermined reaction gas such as SiH ₄ is activated by the activated gas.

Then, from the bias power source 5 to the mounting table 3, for example, 10 KHz to 1
A bias voltage of 3.56 MHz or the like is applied to draw in the activated reaction gas, and the drive device 4 moves the mounting table 3 in the direction of the arrow in the drawing to form a CVD film on the substrate 2 to be processed.

That is, in the plasma processing apparatus of this embodiment, since a discharge is generated between the narrow strip-shaped electrode pair 9a having a small discharge area, a high voltage of, for example, 100 MHz and a voltage of, for example, about 10 ^-1 to 10 ^-3 Torr are used. Discharge can be generated in a state of low vacuum (high pressure).

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

Further, since the film formation is performed while moving the substrate 2 to be processed with respect to the opening 7a and the opening 8a, even if the substrate 2 to be processed is large, a CVD film can be uniformly formed.

[Advantages of the Invention] As described above, in the plasma processing apparatus of the present invention, the discharge area of the discharge due to the AC voltage can be reduced even when the substrate to be processed is large. Therefore, it is possible to generate a discharge with an AC voltage having a higher frequency than in the conventional case, to generate a high-quality plasma with low kinetic energy and high temperature, and to collide with gas molecules converted into plasma. It is possible to reduce damage to the substrate to be processed due to. Further, since the discharge can be generated at a low degree of vacuum (high pressure), the number of particles generated by the polymerization of the decomposed reaction gas can be reduced. Further, since the openings of the gas introducing means are arranged close to each other, it is possible to perform the processing efficiently, and by relatively moving the substrate to be processed and the opening, it is possible to uniformly process the large substrate. can do.

[Brief description of drawings]

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 ... Reaction chamber, 2 ... Substrate to be processed, 3 ... Mounting table, 4 ... Driving device, 7 ... Gas introduction path, 8 ... Reaction gas introduction path, 9a ... Electrode pair, 9b ... High frequency Power supply, 9c ... capacitor.

Claims (3)

[Claims] 1. A reaction chamber for accommodating a substrate to be processed, and a first gas for introducing a first gas, which is turned into plasma by discharge with an AC voltage, into the reaction chamber from a slit-shaped opening.
Gas introduction means, second gas introduction means for introducing a second gas into the reaction chamber from an opening formed so as to sandwich the slit-shaped opening of the first gas introduction means, A substrate and means for relatively moving the slit-shaped opening of the first gas introduction means and the opening of the second gas introduction means, wherein the plasma-converted first gas causes A plasma processing apparatus, wherein the second gas is turned into plasma and a predetermined process is performed on the substrate to be processed. 2. A reaction chamber for accommodating a substrate to be processed, a first gas introduction means for introducing an inert gas plasmatized by discharge with high frequency power into the reaction chamber from a slit-shaped opening, the first gas introduction means. Second gas introducing means for introducing a reaction gas into the reaction chamber through openings formed so as to sandwich the slit-like opening of the gas introducing means, the substrate to be processed, and the slit of the first gas introducing means. -Shaped opening and a means for relatively moving the opening of the second gas introduction means, and the reaction gas is turned into plasma by the inert gas turned into plasma, and the predetermined amount is given to the substrate to be processed. A plasma processing apparatus, which is characterized by performing the above processing. 3. A reaction chamber for accommodating a substrate to be processed, a first gas introduction means for introducing an inert gas plasmatized by discharge by high frequency power into the reaction chamber from a slit-shaped opening, the first gas introduction means. A second gas introducing means for introducing SiH ₄ gas into the reaction chamber from openings formed so as to sandwich the slit-like opening of the gas introducing means; the substrate to be processed; and the first gas introducing means. A slit-shaped opening and a means for moving the opening of the second gas introduction means relative to each other, and the reaction gas is turned into plasma by the inert gas turned into plasma, so that the substrate to be processed is A plasma processing apparatus which performs a predetermined process.