JP2002121677A - Method and apparatus for forming cvd film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the loss of discharge electric power. SOLUTION: A plasma CVD film forming apparatus, by which a film is formed on a substrate by decomposing and reacting a reactive gas with a generated plasma, is provided with a reaction container 11, a ladder electrode 13 which is arranged at a center part in the reaction container 11 and is encircled with a electrode cover 12, heater sources 18a, 18b which are arranged at the both sides of the ladder electrode 13 in the reaction container 11 and support/ heat a substrate 17 at a ladder electrode side, a gas supply mechanism 16 to supply a reaction gas between the ladder electrode 13 and substrate 17, and a high frequency power source 20 electrically connected to the ladder electrode 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma CVD thin film apparatus that effectively utilizes a plasma region.

[0002]

2. Description of the Related Art Conventionally, for example, a plasma CVD thin film apparatus shown in FIG. 7 is known. Reference numeral 1 in the figure is a reaction vessel. In the reaction vessel 1, a heater (heater source) 2 and a ladder-type discharge electrode 3 are arranged to face each other. A substrate 4 is supported by the heater 2 so as to face the discharge electrode 3 side. The discharge electrode 3 has a planar coil configuration in which a plurality of wires having a circular cross section are connected in a ladder shape. The discharge electrode 3 is surrounded by an electrode cover 5. A reactive gas introduction pipe 6 is connected to the electrode cover 5 from outside the vacuum vessel 1. A high-frequency power supply 7 is connected to the discharge electrode 3.

In the plasma CVD thin film apparatus having the above-described structure, when a film is formed, a reactive gas is supplied from a reactive gas introducing pipe 6 to a discharge electrode 3 while a high frequency power is applied from a high frequency power supply 7 to an arrow A. As shown in (1), a reactive gas is supplied to the plasma region R between the discharge electrode 3 and the substrate 4, and the reactive gas is decomposed and reacted by the generated plasma in the region R to form a film on the substrate 4. .

[0004]

However, in the plasma CVD film forming apparatus shown in FIG. 7, the area Q between the back side of the discharge electrode 3, that is, the wall Q between the discharge electrode 3 and the wall surface of the reaction vessel 1 is formed.
In addition, invalid plasma that does not contribute to film formation was generated, and the discharge power was lost.

The present invention has been made in view of the above circumstances, and has a ladder electrode surrounded by an electrode cover in the center of a reaction vessel, and a position facing the inside of the reaction vessel via the ladder electrode. A heater source for supporting and heating the substrate is arranged on the ladder electrode side, and a reactive gas is supplied between the ladder electrode on both sides and the substrate, thereby causing invalid plasma not contributing to film formation. It is an object of the present invention to provide a plasma CVD apparatus capable of reducing a loss of discharge power without generating as much as possible.

Further, according to the present invention, a ladder electrode device having a gas supply function and an electrode function is arranged at a central portion in a reaction vessel, and the ladder electrode device is located at a position facing the inside of the reaction vessel via the ladder electrode device. By arranging a heater source for supporting and heating the substrate on the ladder electrode device side and supplying a reactive gas to the ladder electrode device, without generating invalid plasma that does not contribute to film formation as much as possible. An object of the present invention is to provide a plasma CVD film forming apparatus capable of reducing the loss of discharge power.

Further, the present invention provides a mechanism for changing the distance between the substrate and the electrode, or a configuration in which a power supply for controlling the substrate potential is installed, thereby simultaneously and independently controlling the film forming speed and film quality of a plurality of substrates. Aim.

[0008]

According to a first aspect of the present invention, there is provided a plasma CVD apparatus for forming a film on a substrate by decomposing and reacting a reactive gas with generated plasma. A ladder electrode disposed in the center of the reaction vessel, surrounded by an electrode cover, and a substrate supported on the ladder electrode side disposed at a position facing the ladder electrode in the reaction vessel via the ladder electrode. It is characterized by comprising a heater source for heating, a gas supply mechanism for supplying a reactive gas between the ladder electrode and the substrate, and a high frequency power supply electrically connected to the ladder electrode.

A plasma CVD film forming apparatus according to a second aspect of the present invention is a plasma CVD film forming apparatus for forming a film on a substrate by decomposing a reactive gas by generated plasma.
A reaction vessel and a ladder electrode device having a gas supply function and an electrode function, which are disposed at a central portion in the reaction vessel, and are disposed at positions facing each other via the ladder electrode device in the reaction vessel. The ladder electrode device includes a heater source for supporting and heating a substrate, a gas supply mechanism for supplying a reactive gas to the ladder electrode device, and a high-frequency power supply electrically connected to the ladder electrode device. It is characterized by.

According to a third aspect of the present invention, there is provided a plasma CVD film forming apparatus according to the first or second aspect.
The film forming apparatus further includes a mechanism for changing the distance between the substrate and the electrode, and / or a substrate potential control mechanism.

According to a fourth aspect of the present invention, there is provided a plasma CVD film forming apparatus according to the third aspect, further comprising a mechanism for changing a distance between electrodes and / or a substrate potential control mechanism. The film forming speed and film quality of a plurality of substrates are simultaneously and independently controlled using a CVD film forming apparatus.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail. In the first aspect, the heater source that supports and heats the substrate means a heater source that has a function of heating the substrate while supporting the substrate. The heater source generally includes, but is not limited to, a heater cover and a heater that is disposed inside the heater cover and moves together with the heater cover.

In the first invention, the gas supply mechanism generally includes a gas introduction pipe for supplying a reactive gas into the electrode cover, and a gas cylinder connected to the gas introduction pipe. In the first invention, a large number of gas holes are formed on the electrode cover surface facing the substrate, and a reactive gas is supplied from these gas holes to two plasma regions between the ladder electrode and the substrate.

In the second invention, a ladder electrode device having a gas supply function and an electrode function is provided with a function of supplying a reactive gas between ladder electrodes and between substrates, which is one configuration of the ladder electrode device. A device having both functions of generating a plasma discharge in a plasma region between the substrate and the substrate. The specific configuration of the ladder electrode device is as shown in FIG. 4 described later.

According to the first and second aspects of the present invention, another substrate is disposed also in a region on the back side of the substrate which has been wasted conventionally, and a film is formed. Ineffective plasma that does not contribute to film formation is hardly generated, and loss of discharge power can be reduced.

Further, by providing a mechanism for changing the distance between the substrate and the electrode, the electric field strength between the ladder electrode and the two substrates can be changed since the substrate is usually at the ground potential. The film speed can be controlled simultaneously and independently. For example, by bringing only one substrate close to the ladder electrode, it is possible to control the increase in the film forming speed of only the substrate.

Further, by installing the substrate potential control mechanism, the relative potential with respect to the ladder electrode can be controlled, so that the electric field intensity between the ladder electrode and the two substrates can be changed, and the film forming speed of a plurality of substrates can be reduced. It can be controlled simultaneously and independently. For example, by connecting a DC power supply for biasing the substrate to only one of the substrates, it is possible to control the film forming speed of only the substrate.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. (Embodiment 1) Reference is made to FIGS. Here, FIG. 1 is an overall view of a plasma CVD apparatus according to the first embodiment, and FIG. 2 is an explanatory view of a ladder-type electrode which is a component of the CVD apparatus of FIG.

Reference numeral 11 in the figure denotes a reaction vessel. A ladder-type discharge electrode (hereinafter, referred to as a ladder electrode) 13 surrounded by an electrode cover 12 is provided at a central portion in the reaction vessel 11.
Is arranged. Here, the overall configuration of the ladder electrode 13 is, as shown in FIG.
A plurality of wire members 15 having a circular cross section are connected in a ladder shape.

The electrode cover 12 is connected to a gas supply pipe 16 which is a component of a gas supply mechanism, so that a reactive gas is supplied between the ladder electrode 13 and a substrate described later. In both sides of the ladder electrode 13 in the reaction vessel 11, a substrate 17 is supported on the ladder electrode 13 side, and a heater source 18 for heating the substrate 17 is provided.
a and 18b are arranged respectively. Here, heater source 1
8a and 18b are a heater cover 19 and the cover 19, respectively.
And a heater (not shown) housed therein. A high frequency power supply 20 is connected to the ladder electrode 13.

According to the first embodiment, the ladder electrode 13 surrounded by the electrode cover 12 is disposed at the center of the reaction vessel 11, and the ladder electrode 13 is provided on both sides of the ladder electrode 13 in the reaction vessel 11. Heater sources 18a and 18b for supporting and heating the substrate 17 on the electrode 13 side are arranged respectively.
A reactive gas is supplied between the ladder electrodes 13 on both sides and the substrate 17, and the reactive gas is decomposed and reacted by generated plasma. Thus, in the first embodiment,
Since another substrate is also arranged in the area on the back side of the substrate that was conventionally used unnecessarily, the film is formed, so that invalid plasma that does not contribute to film formation unlike the conventional case is almost generated. Therefore, the loss of discharge power can be reduced.

Embodiment 2 Referring to FIG. 3 and FIG. Here, FIG. 3 is an overall view of a plasma CVD film forming apparatus according to the second embodiment, and FIG. 4 is an explanatory view of a ladder electrode device which is a component of the film forming apparatus. However, the same members as those in FIGS. 1 and 2 are denoted by the same reference numerals, and description thereof will be omitted.

Reference numeral 31 in the figure indicates a ladder electrode device provided at the center of the reaction vessel 11 and having a gas supply function and an electrode function. The ladder electrode device 31 includes a gas manifold 32, 33, which is spaced apart and parallel to each other and has a hollow inside, a ladder electrode 34 disposed between the gas manifolds 32, 33, and the gas manifold 3.
2 and 33 are connected. The ladder electrode 34 is arranged between the gas manifolds 32 and 33, and has a configuration in which a plurality of pipes 36 each having a plurality of gas ejection holes 36a on the substrate 17 side are arranged in a ladder shape. Note that the arrow A in FIG. 4 indicates the gas blowing direction (only a part is shown for convenience).

According to the second embodiment, a ladder electrode device 31 having a gas supply function and an electrode function is arranged at the center of the reaction vessel 11, and both ladder electrode devices 31 are provided in the reaction vessel 11. The ladder electrode device 31 on the side
The heater sources 18a, 18 support and heat the substrate 17 on the side.
b are arranged respectively. Therefore, Example 2
According to the third embodiment, as in the first embodiment, there is almost no generation of ineffective plasma that does not contribute to film formation as in the related art, so that the loss of discharge power can be reduced.

(Embodiment 3) Referring to FIG. 5 and FIG. FIG. 5 is an overall view of a plasma CVD film forming apparatus according to the third embodiment, and FIG. 6 is an explanatory diagram of a ladder electrode device which is one component of the film forming apparatus. However, the same members as those in FIGS. 1 and 2 are denoted by the same reference numerals, and description thereof will be omitted.

On the back of the substrate heater, heater moving devices 41a and 41b movable in the electrode direction are provided. By providing the heater moving devices 41a and 41b, the distance between the electrode and the substrate can be made variable. As a result, for example, when the substrate heater 18a is brought close to the ladder electrode 32 using the heater moving device 41a, only the film forming speed of the film formed on the substrate 17 can be improved. Conversely, the substrate heater 18a is connected to the ladder electrode 3 using the heater moving device 41a.
When the distance is more than 2, only the film forming speed of the film formed on the substrate 17 can be reduced. Since the above control can be performed by using the heater moving device 41b, the film forming speed of a plurality of substrates can be controlled simultaneously and independently.

In FIG. 5, DC power supplies 42a and 42b connected to the substrate heater are provided. DC power supply 42
By providing a and 42b, the electric field strength between the electrode and the substrate can be made variable. As a result, for example, the DC power supply 4
When a positive voltage is applied to the substrate heater 18a using 2a,
Since the ladder electrode 32 is normally negatively biased, the average potential difference between the substrate and the electrode can be increased. As a result, the electric field strength increases and strong plasma is easily generated, so that only the film forming speed of the film formed on the substrate 17 can be improved. Since the above control can be performed by using the DC power supply 42b, the film forming speeds of a plurality of substrates can be controlled simultaneously and independently.

[0028]

As described above in detail, according to the present invention, a ladder electrode surrounded by an electrode cover is disposed in the center of the reaction vessel, and the ladder electrode is provided on both sides of the ladder electrode in the reaction vessel. By disposing a heater source for supporting and heating the substrate on the electrode side and supplying a reactive gas between the ladder electrodes on both sides and the substrate, invalid plasma that does not contribute to film formation is generated as much as possible. Thus, a plasma CVD film forming apparatus capable of reducing the loss of discharge power can be provided.

According to the present invention, a ladder electrode device having a gas supply function and an electrode function is arranged at a central portion in the reaction vessel, and the ladder electrode device is provided on both sides of the ladder electrode device in the reaction vessel. Supports the substrate on the ladder electrode device side
By arranging a heater source for heating and supplying a reactive gas to the ladder electrode device, a plasma capable of reducing a loss of discharge power without generating an ineffective plasma that does not contribute to film formation as much as possible. A CVD film forming apparatus can be provided.

Further, according to the present invention, the film forming speed and the film quality of a plurality of substrates can be simultaneously and independently controlled by using a mechanism for changing the distance between the substrate and the electrode or a configuration in which a power supply for controlling the substrate potential is provided.

[Brief description of the drawings]

FIG. 1 is an overall view of a plasma CVD film forming apparatus according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of a ladder electrode which is a component of the thin film device of FIG.

FIG. 3 is an overall view of a plasma CVD film forming apparatus according to a second embodiment of the present invention.

FIG. 4 is an explanatory diagram of a ladder electrode device which is a component of the thin film device of FIG.

FIG. 5 is an overall view of a plasma CVD film forming apparatus according to a third embodiment of the present invention.

FIG. 6 is an explanatory diagram of a ladder electrode device which is a component of the film forming apparatus of FIG.

FIG. 7 is an overall view of a conventional plasma CVD film forming apparatus.

[Explanation of symbols]

 Reference Signs List 11: reaction vessel, 12: electrode cover, 13, 34: ladder electrode, 14: frame, 15: wire, 16: gas supply pipe, 17: substrate, 18a, 18b: heater source, 19: heater cover, 20 ... High frequency power supply, 31: ladder electrode device, 32, 33: gas manifold, 35: pipe, 36: pipe, 41a, 41b: heater moving device, 42a, 42b: DC power supply.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yoshiaki Takeuchi 5-717-1, Fukahori-cho, Nagasaki-shi, Nagasaki Sanishi Heavy Industries Co., Ltd. Nagasaki Research Laboratory (72) Inventor Hideo Yamakoshi 1-chome, Sachiura, Kanazawa-ku, Yokohama-shi, Kanagawa 8F-1 Mitsubishi Heavy Industries, Ltd. Basic Technology Research Laboratory F-term (reference) 4K030 EA06 FA03 HA13 JA03 JA12 JA17 KA15 KA17 KA23 KA41 5F045 AA08 BB08 DP11 EH04 EH05 EH07

Claims (4)

[Claims] 1. A plasma CVD film forming apparatus for forming a film on a substrate by decomposing a reactive gas by a generated plasma to form a film on a substrate, wherein the reaction container is surrounded by an electrode cover disposed in a central portion of the reaction container. A ladder electrode, a heater source disposed at a position facing the ladder electrode in the reaction vessel via the ladder electrode, and a heater source for supporting and heating a substrate on the ladder electrode side; and supplying a reactive gas between the ladder electrode and the substrate. A plasma CVD film forming apparatus, comprising: a gas supply mechanism for supplying a gas; and a high frequency power supply electrically connected to the ladder electrode. 2. A plasma CVD film forming apparatus for forming a film on a substrate by decomposing a reactive gas by a generated plasma to form a film on a substrate, comprising: a reaction container; a gas supply function and an electrode disposed in a central portion of the reaction container; A ladder electrode device having a function, a heater source disposed at a position facing the inside of the reaction vessel via the ladder electrode device, a heater source for supporting and heating a substrate on the ladder electrode device side, and the ladder electrode device. A plasma CVD film forming apparatus, comprising: a gas supply mechanism for supplying a reactive gas; and a high-frequency power supply electrically connected to the ladder electrode device. 3. The plasma CV according to claim 1, wherein
A plasma CVD film forming apparatus, further comprising a mechanism for changing a distance between a substrate and an electrode and / or a substrate potential control mechanism. 4. A plasma CVD film forming apparatus according to claim 3, wherein a plurality of substrates are formed by using a plasma CVD film forming apparatus further provided with a mechanism for changing a distance between electrodes and / or a substrate potential control mechanism. A plasma CVD film forming method characterized by simultaneously and independently controlling a speed and a film quality.