JP2001023976A - Device and method for treating plasma - Google Patents

Abstract

PROBLEM TO BE SOLVED: To uniformly supply plasma onto the treatment surface of a body to be treated for uniformly treating the body by properly opening and closing a plurality of plasma introduction paths and a plurality of exhaust paths for changing the introduction position of the plasma in a plasma treatment chamber and the exhaust position of atmosphere. SOLUTION: At the ceiling part of a treatment chamber 102 opposite to the placement surface of a mounting rest 106 where a wafer W is placed, introduction pipes 110, 114, and 118 branching from a plasma introduction pipe 132 for introducing a radical into the treatment chamber 102 are formed, and introduction valves 122, 126, and 130 are included into each of them. Also, at the floor part of the treatment chamber 102 at the lower-periphery part of the mounting rest 106, branch exhaust pipes 144 and 148 for discharging gas in the treatment chamber 102 are formed, and exhaust valves 156 and 160 are included into each of them. Then, in the introduction valves 122, 126, and 130, and the exhaust valves 156 and 160, opening is regularly adjusted at each fixed time by a controller 120.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a plasma processing apparatus and a plasma processing method.

[0002]

2. Description of the Related Art Conventionally, there has been proposed a plasma processing apparatus for introducing radicals generated outside a processing chamber into a processing chamber and performing plasma processing on an object to be processed disposed in the processing chamber. In this apparatus, radicals are introduced into the processing surface of the object to be processed in a so-called laminar state or in a downflow state from a certain direction, and gas in the processing chamber is exhausted from a certain direction to flow in a certain direction. Processing is performed by radicals.

[0003]

However, since radicals have high reactivity, the radicals are once diffused in a buffer space provided in the plasma introduction path and then supplied in the above-mentioned laminar flow state, or the radicals are supplied. Even if the radicals diffused in the space are supplied in a downflow state through more small holes, there is a problem that the radicals cannot be uniformly introduced to the entire processing surface of the object to be processed. Furthermore, when radicals pass through the buffer space and small holes, the radicals collide with the walls of the buffer space and small holes and are deactivated, thereby reducing the radical introduction efficiency into the processing chamber. is there.

[0004] The present invention has been made in view of the above-mentioned problems of the prior art, and an object of the present invention is to solve the above problems and other problems. An object of the present invention is to provide a new and improved plasma processing apparatus and method.

[0005]

According to a first aspect of the present invention, there is provided a plasma generating chamber for generating plasma, comprising: In a plasma processing apparatus provided with a plasma processing chamber for introducing and performing plasma processing on an object to be processed, plasma is introduced into the plasma processing chamber via a plurality of plasma introduction paths that can be switched among each other, and an atmosphere in the plasma processing chamber is obtained. Is exhausted through a plurality of exhaust paths that can be switched with each other.

According to the present invention, the flow direction of the plasma in the plasma processing chamber is changed by appropriately opening and closing each plasma introduction path and each exhaust path to change the plasma introduction position and the atmosphere exhaust position in the plasma processing chamber. Can be changed. As a result, the plasma can be evenly supplied to the processing surface of the object, so that the object can be uniformly processed. Further, according to this configuration, it is not necessary to allow the plasma to pass through the buffer space, the small holes, and the like, so that the plasma can be efficiently processed without deactivating the plasma. The plasma is generally composed of charged particles and neutral particles.
Quasi-neutral particles that behave collectively. However, the present invention does not exclude that the plasma introduced into the plasma processing chamber is composed of only neutral particles such as radicals, and the object to be processed is processed only by the neutral particles.

Further, in order to efficiently pass the plasma over the processing surface of the object to be processed and to reliably flow the plasma along the processing surface to the peripheral portion of the object to be processed, for example, the invention as set forth in claim 2 is provided. Preferably, each of the plasma introduction paths is opened on the opposite surface of the object to be processed, and each of the exhaust paths is opened below the periphery of the object to be processed. It is preferable to arrange the openings of the passages and the openings of the exhaust passages at equal intervals in the circumferential direction.

Further, in order to regularly change the flow direction of the plasma in the plasma processing chamber to a different direction, for example, the opening and closing of each plasma introduction path and the opening and closing of each exhaust path are performed as in the invention according to the fourth aspect. It is preferable to provide a means for controlling the opening and closing in time series. According to such a configuration, since plasma can be introduced to the entire processing surface of the object to be processed without generating a portion where plasma is not introduced, uniform processing can be performed.

According to a second aspect of the present invention, the plasma generated in the plasma generation chamber is introduced into the plasma processing chamber and arranged in the plasma processing chamber as in the invention according to claim 5. In a plasma processing method for performing plasma processing on an object to be processed, plasma is introduced into a plasma processing chamber through a plurality of mutually switchable plasma introduction paths, and an atmosphere in the plasma processing chamber is formed by a plurality of mutually switchable exhaust paths. The plasma processing method is characterized by being evacuated via a plasma processing method.

With this configuration, the plasma introduction position and the atmosphere exhaust position can be changed by opening and closing the respective plasma introduction paths and the respective exhaust paths, and the flow direction of the plasma in the plasma processing chamber can be changed. Can be uniformly supplied to the entire processing surface of the object to be processed.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a preferred embodiment in which a plasma processing apparatus and a plasma processing method according to the present invention are applied to an oxidation processing apparatus and an oxidation processing method will be described in detail with reference to the accompanying drawings. .

(1) Configuration of Oxidation Processing Apparatus The processing chamber 102 of the oxidation processing apparatus 100 shown in FIG. 1 is formed in an airtight processing vessel 104. Processing room 1
02, an object to be processed, for example, a semiconductor wafer (hereinafter, referred to as a semiconductor wafer)
Called "wafer". A) A mounting table 106 on which W can be mounted is arranged. The processing container 104 and the mounting table 1
No. 06 is made of aluminum whose surface is anodized.

As shown in FIGS. 1 and 2, a plasma introduction pipe 132 for introducing radicals into the processing chamber 102 is provided at the ceiling of the processing chamber 102 facing the mounting surface of the mounting table 106. First branch according to the present embodiment
-Fifth branch introduction pipe 110, 112, 114, 116, 1
Eighteenth first to fifth inlets 110a, 112a, 114
a, 116a and 118a are formed. First to fifth
Inlets 110a, 112a, 114a, 116a, 11
As shown in FIG. 3, when the wafer W is mounted on the mounting table 106 so that radicals can be introduced into the surface of the wafer W, as shown in FIG. Is formed. Further, in the illustrated example, first to fifth
Inlets 110a, 112a, 114a, 116a, 11
8a is the second through fifth centering on the first inlet 110a.
The inlets 112a, 114a, 116a, 118a are arranged at equal intervals in the radial and circumferential directions. With this configuration, radicals can be introduced into a plurality of locations on the surface of the wafer W during processing.

As shown in FIG. 1 and FIG.
-Fifth branch introduction pipe 110, 112, 114, 116, 1
18, the first to fifth inlets according to the present embodiment for adjusting the flow rate of radicals passing through the first to fifth branch inlet pipes 110, 112, 114, 116, 118 under the control of the controller 120. Valves 122, 124, 126, 12
8, 130 are interposed correspondingly. The first to fifth introduction valves 122, 124, 126, 1
The adjustment of the opening degrees of 28 and 130 will be described later.

The first to fifth branch introduction pipes 110, 11
2, 114, 116, 118, and a plasma introduction tube 132
Are made of, for example, quartz, and are set to an inner diameter and a length such that the radicals are not deactivated during passage of the radicals. In addition, the first to fifth branch introduction pipes 110, 112,
The pipes 114, 116, 118 and the plasma introducing tube 132 are arranged so that bent portions are not formed as much as possible so that the radicals do not collide with the wall and be deactivated. However, ions and electrons that adversely affect the processing are supplied to the plasma introduction tube 132 together with radicals from a cavity 138 described later, and the ions and electrons are more easily deactivated by collision with the wall than the radicals. have. Therefore,
Plasma introduction tube 132 or first to fifth branch introduction tubes 1
10, 112, 114, 116, 118, for example,
Fifth branch introduction pipes 110, 112, 114, 116, 11
8, bent portions 110b, 112b, 112c, 114
If b, 116b, 116c, and 118b are provided correspondingly, radicals required for processing can be selectively removed from the processing chamber 1.
02 can be introduced.

As shown in FIG. 1, one end of the plasma introduction tube 132 is connected to a microwave
A predetermined frequency introduced via 36, for example 2.45G
The microwave is arranged in a cavity 138 for introducing a microwave of Hz into the plasma introduction tube 132 to constitute a plasma generation chamber. The waveguide 136 and the cavity 138
Is made of, for example, stainless steel. With this configuration, when a processing gas, for example, O ₂ is introduced from the processing gas source 140 into the plasma introduction pipe 132 via the opening / closing valve 142, the O ₂ is turned into plasma by the action of microwaves when passing through the cavity 138, and becomes oxygen. Radicals, ions, and electrons are generated. Among the generated oxygen radicals and the like, ions and electrons are introduced into the plasma introduction tube 132 and the first to fifth branch introduction tubes 110, 112, 114,
It disappears as described above when passing through 116 and 118. Therefore, oxygen radicals are generated by the first to fifth inlets 110a, 112a.
a, 114a, 116a, and 118a are introduced to the surface of the wafer W in the processing chamber 102, and the oxygen radical oxidizes the Si layer of the wafer W to form a SiO ₂ film.

On the other hand, the processing chamber 10 below the mounting table 106
As shown in FIGS. 1, 3 and 4, the first to fourth branch exhaust pipes 144 and 146, which are features of the present embodiment, for exhausting the gas in the processing chamber 102, , 14
8, 150 first to fourth exhaust ports 144a, 146a, 1
48a and 150a are formed at substantially equal intervals in the circumferential direction. In the present embodiment, as shown in FIG.
Although the first and third branch exhaust pipes 144 and 148 and the first, third and fifth branch introduction pipes 110, 114 and 118 are not arranged in the same cross section, the first and third branch pipes are shown in FIG. The exhaust pipes 144, 148 and the first, third and fifth branch introduction pipes 110, 114, 118 are shown together.

As shown in FIG. 1 and FIG.
-The fourth branch exhaust pipes 144, 146, 148, 150
It is connected to a vacuum pump P154 via an exhaust pipe 152. Further, the first to fourth branch exhaust pipes 144, 146, 1
48 and 150, the first to fourth branch exhaust pipes 144, 146, 148, and 150 according to the present embodiment for adjusting the exhaust amount of gas passing through the first to fourth branch exhaust pipes 144, 146, 148, and 150 under the control of the controller 120. 4 exhaust valves 156, 158, 160, 16
2 are interposed correspondingly. In addition,
The adjustment of the degree of opening of the fourth exhaust valves 156, 158, 160, 162 will be described later.

(2) First to fifth introduction valves and first to fifth introduction valves
Adjustment of opening degree of fourth exhaust valve First to fifth introduction valves 122, 124, 126, 12
8, 130 and the first to fourth exhaust valves 156, 15
8, 160 and 162, the opening degree is regularly adjusted by the controller 120 shown in FIG. 1 at regular intervals according to the timing chart shown in FIG.

First, from the time T0 to the time T1 at the start of the process, the first to fifth introduction valves 122, 124, 126, 1
28, 130 and the first to fourth exhaust valves 156, 15
8, 160 and 162 are all released. As a result, FIG.
As shown in (a), the first to fifth inlets 110a, 11a
After radicals are introduced from all of 2a, 114a, 116a, and 118a toward the entire surface of the wafer W, the wafer W
The gas that has passed through the surface is first to fourth exhaust ports 144a and 144a.
Air is exhausted from all of 6a, 148a, and 150a. For convenience of explanation, FIG. 6A shows only the first, third and fifth branch introduction pipes 110, 114 and 118 and the first and third branch exhaust pipes 144 and 148, and FIG.
6 (b) and FIG. 6 (c) show only the first, second and fourth branch introduction pipes 110, 112 and 116 and the first and second branch exhaust pipes 144 and 146.

Next, from the time T1 to the time T2, the second introduction valve 124, the second and third exhaust valves 158,
While keeping 160 open, the other valves are closed. As a result, as shown in FIG. 6B, radicals are introduced from the second inlet 112a, and the gas in the processing chamber 102 is exhausted from the second and third exhaust ports 146, 148. Flows on the wafer W from the second introduction port 112a to the second and third exhaust ports 146, 148.

Similarly, from time T2 to time T3, the third introduction valve 126 and the third and fourth exhaust valves 16
0, 162 is released, and the radicals
The third and fourth exhaust valves 16 from the inlet 114a side
It flows to the 0,162 side. Also, from T3 to T4, the fourth introduction valve 128 and the first and fourth exhaust valves 156 and 162 are opened, and as shown in FIG. Conversely, radicals flow on the wafer W from the fourth introduction port 116a to the first and fourth exhaust ports 144a and 150a. Further, from the time T4 to the time T5, the fifth introduction valve 130 and the first and second exhaust valves 156 and 158 are opened, and the T2
Contrary to the period from time t3 to time t3, radicals flow over the wafer W from the fifth inlet port 118a side to the first and second exhaust valves 14a and 14b.
4a and 146a. From the time T5 to the end of the process, the above-described steps from the time T0 to the time T5 are sequentially repeated.

As described above, from T0 to T1, radicals are introduced into the entire surface of the wafer W, and from T1 to T5, radicals are introduced.
The flow of the radicals is sequentially changed in a clockwise manner, and the above operations are continuously performed from the start to the end of the process. As a result, as a whole,
Since the radicals are uniformly introduced into the processing surface of the wafer W from a plurality of directions, the radicals can be uniformly introduced over the entire surface of the wafer W, and a uniform oxidation treatment can be performed. Note that the first to fifth introduction valves 122, 124, and 1 are arranged so that the flow of the radicals sequentially changes counterclockwise.
26, 128, 130 and the first to fourth exhaust valves 15
6,158,160,162 opening degree adjustment may be performed.

The preferred embodiment of the present invention has been described above with reference to the accompanying drawings, but the present invention is not limited to this configuration. In the scope of the technical idea described in the claims, those skilled in the art
Various changes and modifications can be conceived, and it is understood that these changes and modifications also belong to the technical scope of the present invention.

For example, in the above-described embodiment, a configuration in which five inlets and four exhaust ports are provided in the processing chamber has been described as an example. However, the present invention is not limited to such a configuration, and radical flow is not limited to this configuration. The present invention can be implemented even if an arbitrary number of air supply ports and exhaust ports are provided in the processing chamber as long as the processing can be controlled.

Further, in the above embodiment, from T0
At each time other than T1, a configuration in which radicals are introduced from one inlet and gas is exhausted from two outlets has been described as an example, but the present invention is not limited to such a configuration. The present invention can be implemented by adopting a configuration in which radicals are introduced from an arbitrary number of introduction ports and exhausted from an arbitrary number of exhaust ports.

Further, in the above-described embodiment, a configuration in which the wafer is oxidized by oxygen radicals generated from O ₂ has been described as an example. However, the present invention is not limited to such a configuration. _Using a mixed gas of O ₂ and O ₂ as a processing gas, subjecting the object to oxynitriding with the generated nitrogen radicals and oxygen radicals, or using N ₂ as a processing gas to generate the generated nitrogen radicals Accordingly, the present invention can be applied to the case where the object to be processed is subjected to nitriding.

[0028]

According to the present invention, radicals generated outside the processing chamber can be uniformly introduced into the object to be processed disposed in the processing chamber, and uniform processing can be performed.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an oxidation treatment apparatus to which the present invention can be applied.

FIG. 2 is a schematic perspective view showing an upper part of the oxidation treatment apparatus shown in FIG.

FIG. 3 is a schematic explanatory view for explaining an arrangement position of an inlet and an outlet of the oxidation treatment apparatus shown in FIG. 1;

FIG. 4 is a schematic perspective view showing a lower portion of the oxidation treatment apparatus shown in FIG.

FIG. 5 is a schematic timing chart for explaining opening and closing timings of an introduction valve and an exhaust valve of the oxidation treatment apparatus shown in FIG. 1;

FIG. 6 is a schematic explanatory view for explaining a flow of radicals at the time of processing by the oxidation processing apparatus shown in FIG. 1;

[Explanation of symbols]

Reference Signs List 100 oxidation treatment apparatus 102 processing chamber 106 mounting table 110, 112, 114, 116, 118
Fifth branch introduction pipe 110a, 112a, 114a, 116a, 118a
First to fifth inlet ports 120 Controllers 122, 124, 126, 128, 130
Fifth introduction valve 132 Plasma introduction tube 138 Cavity 140 Processing gas source 144, 146, 148, 150 First to fourth branch exhaust pipes 144a, 146a, 148a, 150a First to fourth
Fourth exhaust port 152 Exhaust pipe 154 Vacuum pump 156, 158, 160, 162 First to fourth exhaust valves W Wafer

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masahito Sugiura 650 Mitsuzawa, Hosakacho, Nirasaki, Yamanashi Prefecture Tokyo Electron Co., Ltd. (72) Inventor Shintaro Aoyama 650 Mitsuzawa, Hosakacho, Nirasaki, Yamanashi Tokyo Electron Corporation F Terms (reference) 5F045 AA09 AA16 AB32 AB33 AB34 AC11 AC15 AF03 BB02 BB08 DP03 EC08 EE18 EF02 EF08 EF09 EF20 EG02 EG06 EH03 EH18 EM09 GB15

Claims (5)

[Claims] 1. A plasma generation chamber for generating plasma,
In a plasma processing apparatus, the plasma processing apparatus includes: a plasma processing chamber configured to perform plasma processing on an object to be processed by introducing the plasma.
The plasma is introduced into the plasma processing chamber through a plurality of mutually switchable plasma introduction paths, and an atmosphere in the plasma processing chamber is exhausted through a plurality of mutually switchable exhaust paths. Plasma processing equipment. 2. The plasma processing apparatus according to claim 1, wherein each of the plasma introduction paths is opened at a surface facing the object to be processed, and each of the exhaust paths is opened below the periphery of the object to be processed. Plasma processing equipment. 3. The plasma processing apparatus according to claim 2, wherein an opening of each of the plasma introduction paths and an opening of each of the exhaust paths are arranged at equal intervals in a circumferential direction. 4. The plasma processing apparatus according to claim 1, further comprising means for controlling the opening and closing of each of the plasma introduction paths and the opening and closing of each of the exhaust paths in a time-series manner. apparatus. 5. A plasma processing method for introducing plasma generated in a plasma generation chamber into a plasma processing chamber and performing plasma processing on an object to be processed disposed in the plasma processing chamber: the plasma can be switched mutually. A plasma processing method, wherein the plasma processing chamber is introduced into the plasma processing chamber through a plurality of plasma introduction paths, and the atmosphere in the plasma processing chamber is exhausted through a plurality of mutually switchable exhaust paths.