JP3155199B2 - Plasma processing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a plasma processing apparatus for performing a plasma process on an object to be processed such as a semiconductor wafer.

[0002]

2. Description of the Related Art Generally, in order to manufacture a semiconductor device, a predetermined film is formed on a wafer, or an etching process is performed to form a predetermined circuit pattern on the film. A desired circuit element is formed by repeating these film formation and etching many times. The line width of a circuit pattern becomes extremely fine as the semiconductor device becomes more highly integrated and higher in density. For example, a line width of the order of submicron is required. In order to improve the yield of semiconductor devices, this fine pattern must be formed with high accuracy. However, when performing various processes, it is a major issue how to avoid the generation of particles that cause the yield to deteriorate. .

In order to perform various kinds of processing on a semiconductor wafer, a plasma processing apparatus using plasma is often used in addition to a heat treatment apparatus because of a high processing efficiency in a single wafer type. FIG. 11 shows a schematic configuration diagram of a general plasma processing apparatus. In a processing vessel 2 made of, for example, aluminum alumite, a susceptor 6 provided on an insulator 4 is provided. For example, a semiconductor wafer W as a processing body is suction-held by an electrostatic chuck or the like. The susceptor 6 also serves as a lower electrode.
High-frequency power supply 10 for generating a high frequency of
High-frequency power for plasma generation can be supplied into the processing container 2. An exhaust port 12 connected to a vacuum exhaust system (not shown) provided with a vacuum pump or the like is provided at the bottom of the processing container 2 so that the inside of the container can be evacuated.

[0004] A ceiling 16 is provided facing the susceptor 6.
Is provided with a shower head section 14 made of, for example, aluminum alumite for introducing a processing gas or a plasma gas into the processing chamber 2, and the shower head section 14 also serves as an upper electrode. FIG. 12 shows a partially enlarged sectional view of the shower head section 14, and FIG. 13 shows a plan view thereof. As shown in the figure, a large number of gas flow passages 20 are formed in the shower head portion 14, and by opening the lower end, a large number of gas ejection holes 18 are provided on the lower surface so as to be scattered over substantially the entire surface. Thus, the introduced gas and the like can be supplied substantially uniformly within the wafer surface. FIG.
Shows an enlarged view of the gas ejection hole 18. The diameter L1 of the gas ejection hole 18 is set to, for example, about 0.5 to 0.8 mm in order to narrow the gas amount, and is extremely small. The tip is provided with a tapered surface 18A so as to expand so as to reduce the acute angle portion so as to minimize the electric field concentration which causes plasma attraction. Reference numeral 22 denotes a rotating magnet that creates a magnetic field for increasing the density of plasma.

[0005]

When a wafer is processed, plasma is generated in a processing space between the shower head section 14 and the susceptor 6, and the lower surface of the head section that comes into direct contact with the plasma is generated. Although a tapered surface 18A for reducing electric field concentration is formed in the gas ejection hole 18, it is inevitable that an obtuse corner is generated in this portion due to difficulty in processing. For this reason, it is still inevitable that electric field concentration occurs in this portion. If the head is used to some extent, even though the head lower surface is treated with high-quality alumite having a thickness of about 50 μm, the portion of the gas ejection hole 18 which receives the electric field concentration However, the particles tend to peel off due to the sputtering by the plasma, and aluminum on the background is exposed, which has caused particles.

If the aluminum background is exposed by sputtering, the entire showerhead 14 must be replaced, which not only shortens the service life but also increases the cost. Therefore, in order to further reduce the electric field concentration, the tapered surface 18 of the gas ejection hole 18 is used.
It is conceivable that the portion A is curved. In this case, the diameter L1 of the gas ejection hole 18 is 0.5
Since the diameter is set to about 0.8 mm, the diameter is too small and it is very difficult to perform a curved surface processing. Also, since a very large number of gas ejection holes 18 are provided at about 150 to 180, Costs will also rise. The present invention has been devised in view of the above problems and effectively solving them. SUMMARY OF THE INVENTION It is an object of the present invention to provide a plasma processing apparatus in which a gas supply head portion has a structure capable of alleviating a concentration of an electric field of plasma to suppress surface separation.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a processing vessel capable of being evacuated,
A mounting table for mounting an object to be processed, which is accommodated in the processing container, a gas supply head arranged to face the mounting table for supplying a processing gas, and generating plasma in the processing container in the plasma processing apparatus and a high frequency power supply for supplying high frequency power, the gas supply head portion
Has a circular bottom surface, from the center to the outer edge
A head body having a gas passage toward the head, and the head
The body is arranged along the circumferential direction at the lower outer peripheral end of the main body.
A ring-shaped gas ejection groove is formed between the outer edge of the head body
A ring groove forming member to be formed;
Disposed on the outer periphery of the groove forming member and
More becomes a holding member for holding the ceiling portion, thereby forming a surface defining an opening for pre-forming a cut ring-shaped gas ejection groove so that the curved surface, the ring-shaped ring interposition
The component is configured to be divided into a plurality .

[0008] With the above construction, the gas supply head in the processing vessel has a ring-shaped gas ejection groove on its lower surface, and the processing gas is supplied from the gas ejection groove. . In this case, the gas supply head is
It is constituted by a head main body, a ring groove forming member, and a holding member, and a portion defining a ring-shaped opening of the gas ejection groove is machined into a curved surface shape. Thereby, it is possible to reduce the concentration of the electric field of the plasma and to suppress the surface peeling due to the sputtering.

By interposing a thermal expansion allowing elastic member between the holding member and the ring groove forming member, not only can the thermal expansion of the head body be absorbed, but also the mounting accuracy can be improved and the gas ejection groove can be formed. The width can be kept uniform. Furthermore, by dividing the ring-shaped ring groove forming member into a plurality, the mounting can be easily performed. A plurality of such gas ejection grooves may be provided concentrically, and in one case, the diameter of the gas ejection grooves is set to be substantially the same as the radius of the object to be processed, so that the gas drift is reduced. In addition, in-plane uniformity of plasma processing can be ensured.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the plasma processing apparatus according to the present invention will be described below in detail with reference to the accompanying drawings. FIG.
Is a cross-sectional configuration diagram showing a plasma processing apparatus of the present invention, FIG. 2 is an enlarged cross-sectional view showing a gas supply head portion of the apparatus shown in FIG.
3 is a bottom view of the head portion shown in FIG. 2, FIG. 4 is a partial cross-sectional side view showing a head body of the gas supply head portion, FIG. 5 is a plan view of the head body, and FIG. FIG. 7 is a plan view of a ring groove forming member, and FIG. 8 is a cross-sectional view showing a holding member of a gas supply head. In the present embodiment, a description will be given of a case where the plasma processing apparatus 24 is applied to a plasma etching apparatus that performs an etching process on a semiconductor wafer as an object to be processed.

The plasma processing apparatus 24 has an airtight processing container 26 made of, for example, aluminum whose surface is anodized and formed in a cylindrical shape or a rectangular cylindrical shape. Mounting table 3 made of, for example, aluminum alumite supported on a base 28
A semiconductor wafer W as an object to be processed is placed on this upper surface.

On the upper surface of the mounting table 30, an electrostatic chuck (not shown) for holding the wafer by electrostatic attraction is provided. Although only a plurality of the mounting tables 30 and two in the illustrated example are shown on the mounting table 30, three lifter pins 34 are actually provided so as to be able to move up and down therethrough. When the wafer is transferred, it can be pushed up and down. A stretchable metal bellows 36 is provided between the lower portion of the lifter pin 34 and the mounting table 30 to allow the lifter pin 34 to move up and down while maintaining airtightness. Further, a cooling jacket 38 for cooling the wafer W to a predetermined temperature is provided in the mounting table 30, and a coolant flows through the cooling jacket 38. The mounting table 30 is connected via a matching circuit 40 to a high-frequency power source 42 that generates a high frequency of 13.56 MHz, for example.
A high frequency power for plasma generation can be supplied to the inside.

The processing container 26 is grounded, and a ceiling portion 46 is provided above the processing container 26 via a sealing member 44 such as an O-ring.
A gas supply head 48, which is a feature of the present invention, is attached to the ceiling 46 so as to face the mounting table 30. This gas supply head section 48
A ring-shaped gas ejection groove 50 is formed on the lower surface side of the processing chamber so that a processing gas can be supplied into the processing chamber as described later. The gas introduction unit 54 of the gas supply head unit 48 is connected to branch pipes 52A, 52B, and 52C that are branched into three in order to supply an etching gas. CHF ₃ as a gas source through a valve 56 and an on-off valve 58
They are connected to a gas source 60, a CF ₄ gas source 62 and an Ar gas 64, respectively.

The gas supply head 48 also functions as an upper electrode, and generates plasma in a processing space between the gas supply head 48 and the mounting table 30 below. A rotating magnet 66 is provided above and in close proximity to the ceiling 48 to form a horizontal magnetic field for increasing the density of plasma in the processing space. A loading / unloading port 68 for loading / unloading a wafer is provided on a side wall of the processing container 26, and the loading / unloading port 68 is connected to a load lock chamber 72 via a gate valve 70 which opens and closes the opening / closed airtightly.
Is attached. An exhaust port 73 connected to a vacuum exhaust system (not shown) is provided at the bottom peripheral edge of the processing container 26.

Next, the configuration of the gas supply head section 48 will be described. As shown in FIGS. 2 to 8, the gas supply head section 48 includes a disc-shaped head body 74 located at the center.
And a ring-shaped ring groove forming member 76 provided on the outer periphery of the lower end, and a holding member 78 for attaching and holding the head body 74 and the ring groove forming member 76 to the ceiling 46, and The ring-shaped gas ejection groove 50 is defined and formed by slightly separating the lower end outer peripheral surface of the head main body 74 and the lower end inner peripheral surface of the ring groove forming member 76.

The holding member 78 is provided with a fitting hole 80 having a stepped inner surface for fitting and supporting the head body 74 and the ring groove forming member 76 at the center thereof. Further, a gas supply groove 84 communicating with a gas introduction hole 82 provided in the ceiling portion 46 is formed on the upper surface, and a gas path is formed by attaching the gas supply groove 84 to the lower surface of the ceiling portion 46. Configuration. The entire holding member 78 is made of, for example, aluminum whose lower surface and side surfaces are anodized, and maintains high durability against plasma. Instead of alumite treatment, it may be coated with alumina ceramic. Further, a sealing member 86 such as an O-ring is provided at a peripheral edge of the upper surface of the holding member 78 to maintain a sealing property with respect to the lower surface of the ceiling portion. You.

The periphery of the disk-shaped head body 74 is
It is formed stepwise so as to be fitted into the fitting hole 80 of the holding member 78 (see FIGS. 4 and 5), and its lower end portion is formed between the lower end inner peripheral surface of the holding member 78 and the ring groove forming member. The diameter is set small so as to be able to accommodate 76. A gas supply groove 88 communicating with the gas supply groove 84 of the holding member 78 is formed on the upper surface of the head body 74 toward the center. The gas supply groove 88 is attached to the lower surface of the ceiling 46 to form a gas path. It is supposed to.

A plurality of gas passages 90 are formed in the lower portion of the head body 74 and extend radially from the center of the head body 74 and open to the outer peripheral end. The gas passages 90 and the gas supply grooves 88 are formed. It is communicated at the center of the head body 74. These gas passages 90 can be formed, for example, by drilling with a drill or the like. In the illustrated example, eight gas passages 90 are provided radially. Therefore, the gas flowing through the gas supply groove 88 is dispersed in the eight gas passages 90 and can be ejected from the tips. A plurality of bolt holes 92 are provided at equal intervals in the periphery of the head main body 74, and these are fixed to the holding member 78 with bolts 94 (see FIG. 2). A sealing member 96 made of, for example, an O-ring or the like is interposed on the joint surface between the head body 74 and the holding member 78 in order to ensure the sealing property between the two. The head main body 74 is also made of, for example, anodized aluminum on the lower surface and side surfaces, and has improved durability against plasma. Here, it may be coated with alumina ceramic instead of the alumite treatment.

As shown in FIGS. 6 and 7, an outer engaging projection 98 is formed on the outer periphery of the ring groove forming member 76, and an inner engaging projection 100 is formed on the inner periphery thereof. Engaging step 102 (see FIG. 8) and head body 7
4 are supported by the four engaging recesses 104 (see FIG. 4). In addition, a plurality of the ring groove forming members 76 are provided.
For example, it is divided into two in the diameter direction, so that it can be easily assembled. This ring groove forming member 7
6 is enlarged in FIG. 9, and the length L2 of the inner engaging projection 100 of the ring groove forming member 76 is
The width L4 of the ring-shaped gas ejection groove 50 is set to be slightly longer than the depth L3 of the engagement concave portion 104 of the head main body 74, for example, about 0.5 mm. The difference between the depths L3, that is, 0.5 mm is set. These dimensions are examples and are not limiting.

The outer engaging projection 98 of the ring groove forming member 76 is placed in a loosely fitted state on the engaging step 102 of the holding member 78 so as to be able to move in the radial direction. The distal end of the portion 98 does not contact the holding member 78. Further, in order to allow the ring groove forming member 76 to move in the radial direction, a predetermined distance L5 is provided between the outer peripheral surface and the inner peripheral surface of the engagement step portion 102. The distance L5 is set to, for example, about 0.25 mm in consideration of the amount of thermal expansion as described later. A ring-shaped thermal expansion allowable elastic member 106 is interposed between the outer engaging projection 98 and the holding member 78, and constantly urges the ring groove forming member 76 radially inward. At the same time, the thermal expansion can be absorbed by the contraction of the elastic member 106. Further, the ring groove forming member 76 includes:
Since the elastic member 106 is urged in the center direction, the distal end of the inner engaging projection 100 and the deep portion of the engaging recess 104 of the head main body 74 are always in contact with each other. Since the width L4 can be constantly maintained irrespective of the temperature, the flow rate of the gas flowing therethrough can be stabilized.

As the thermal expansion allowable elastic member 106,
A member having elasticity and heat resistance to some extent, for example, an O-ring made of Viton, an elastic metal ring, or the like can be used. Further, here, in order to reduce the electric field concentration of the plasma, the lower end outer peripheral end 108 of the head main body 74 and the lower end inner peripheral end 110 of the ring groove forming member 76 which define the opening 50A of the gas ejection groove 50 are rounded. It is processed into a curved surface. Similarly, a lower end outer peripheral end 112 of the ring groove forming member 76 and a lower end inner peripheral end 1 of the holding member 78 opposed thereto.
14 is also processed into a curved surface with a radius. The curvature of this curved surface is set to a value larger than 1 mm, preferably about 2 mm. Since these curved surfaces are separate members that can be individually separated from each other, it is possible to easily perform the processing unlike the case of the conventional ejection hole.

The material of the ring groove forming member 76 is, for example, Al having particularly high durability against plasma.
Ceramics made of ₂ O ₃ or ZrO ₂ (zirconia) can be used. Alternatively, aluminum whose surface is anodized can be used. The head body 74, the ring groove forming member 76, and the holding member 78 are assembled so as to be at the same horizontal level so that their lower surfaces do not project. Here, when the wafer size is 8 inches (20 cm), the diameter of the lower end surface of the head main body 74, that is, the ring-shaped gas ejection groove 50 is approximately half of the wafer size, for example, 7 cm to 13c.
It is set within a range of about m, so that the gas is prevented from drifting and the uniformity of the plasma processing is ensured. That is, the diameter of the ring-shaped gas ejection groove 50 is preferably 35 to 65% of the diameter of the wafer. In this case, the thickness of the ring groove forming member 76 is approximately 5 to 9 mm.
Set to about.

Next, the operation of the present embodiment configured as described above will be described. First, a semiconductor wafer W to be etched is loaded into a load lock chamber 7.
2 is carried into the processing vessel 26 through the gate valve 70,
This is sucked and fixed by an electrostatic chuck (not shown). Then, the inside of the processing container 26 is evacuated and the etching gas is supplied from the gas supply head unit 48 while maintaining the pressure at a predetermined value.
Is applied to the mounting table 30 as a lower electrode to generate plasma in a processing space between the mounting table 30 and a gas supply head unit 48 as an upper electrode of a ground potential, thereby etching an oxide film or the like on a wafer surface. Perform An example of the etching conditions at this time is, for example, a process pressure of about 3
00 mTorr, high-frequency power is about 1300 W (watt), and gas flow rates are about 30 sccm, 30 sccm and 600 sccm for CHF ₃ , CF ₄ and Ar gas, respectively. The temperature of the mounting table 30 is controlled by the cooling jacket 38.
-10 ° C. respectively. It is needless to say that these process conditions are merely examples.

The processing gas introduced from the gas introduction part 54 of the gas supply head part 48 is supplied to the gas supply groove 8
4 and 88, and flows radially toward the periphery of the head main body 74 from the center through a gas passage 90 provided in the head main body 74. This gas is
Further, the gas is discharged from the gas ejection groove 50 provided in a ring shape along the outer periphery of the head main body 74 toward the lower processing chamber,
It will be turned into plasma. Here, the gas ejection surface on the lower surface of the gas supply head unit 48 is always exposed to plasma during processing, but the corners of the members that define the opening of the gas ejection groove 50, which is the portion exposed to plasma, Since the corners where the members are joined are made into a curved surface shape,
The occurrence of plasma electric field concentration at this portion can be suppressed, and surface separation can be prevented. That is, FIG.
As shown in the figure, the lower end outer peripheral end 108 of the head main body 74, the lower end inner peripheral end 110 of the ring groove forming member 76, the lower end outer peripheral end 112 of the ring groove forming member 76, and the lower end inner peripheral end 114 of the holding member 78 are respectively formed. In addition, since the curved surface is formed, the occurrence of electric field concentration can be reduced.

As described above, since the electric field concentration can be reduced, the surface can be prevented from being peeled off by sputtering, and not only the generation of particles can be suppressed and the yield can be improved, but also the yield can be improved. The life of the member can be extended. In particular, by forming the ring groove forming member 76 having a small volume and not significantly affecting the plasma generation from a ceramic material having high plasma durability, the generation of particles can be further suppressed. The radius of curvature of the curved surface as described above is larger than 1 mm in order to exhibit the effect of alleviating the electric field concentration, and is excessively large considering that the width L4 of the gas ejection groove 50 is about 0.5 mm. I can't do it,
For example, about 2 mm is optimal. This value is similarly applied to the curved surface of other parts. In such a curved surface processing, the gas ejection surface is not an integral structure as in the conventional shower head structure, but in the present invention, there are roughly three members,
That is, since the head body 74, the ring groove forming member 76, and the holding member 78 are divided, the curved surface processing can be easily performed in the divided state.

When the alumite on the surface is peeled off due to long-term use, only the severely damaged member of the above three members needs to be replaced, and the entire gas supply head is replaced. Since there is no need, maintenance costs can be reduced. Further, during the processing, the gas supply head 48 is heated to, for example, about 100 ° C., depending on the processing conditions, so that the member itself thermally expands. However, the ring groove forming member 76 is divided into a plurality, Moreover, as shown in FIG. 9, the thermal expansion permitting elastic member 106 having elasticity constantly presses and urges inward in the radial direction to abut on the engaging recess 104 of the head main body 74 (see FIG. 9). The expansion and contraction of the elastic member 106 can absorb the thermal expansion of the member, so that the width L4 of the gas ejection groove 50 can always be accurately maintained at a constant value as designed, including during assembly. Becomes

In this case, when the dimensions are as large as those in the present embodiment, the thermal expansion of the head body 74 is about 0.1 mm, and the width L5 between the holding member 78 and the ring groove forming member 76 is smaller than that. Is also a slightly larger value, that is, 0.
Since it is set to 25 mm, there is no restriction on thermal expansion. Further, the width L4 is kept constant along the circumferential direction of the ring for the above-mentioned reason, and the width L4 is partially maintained.
Are not different from each other, so that the flow rate of the gas to be jetted therefrom can be uniformly supplied without uneven distribution.

FIG. 10 shows an evaluation graph when an etching process is actually performed by the above-described apparatus of the present invention and an apparatus having a conventional shower head structure having a large number of injection holes. The diameter of the wafer at the time of evaluation was 6 inches (150 mm), and the diameter of the ring-shaped gas ejection groove was 89 mm. FIG. 10A shows the etch rate of the device of the present invention, and FIG. 10B shows the etch rate of a device having a conventional shower head structure. In the graph, the X axis and the Y axis indicate the evaluation directions on the wafer surface,
Both axes are orthogonal. Here, other process conditions were the same except for the configuration of the head portion. The process conditions are
Processing pressure is 40 mTorr, high frequency power is 800 W, C
HF ₃ is 74 sccm, CF ₄ is 78 sccm, the upper electrode is 60 ° C., and the mounting table temperature is 20 ° C.

As is clear from the graph, even when the processing gas is supplied from a large number of ejection holes dispersed over the entire showerhead surface as in the conventional structure, one ring-shaped gas ejection groove is provided as in the present invention. It can be seen that the in-plane uniformity of the plasma etch is maintained within the allowable range both when the gas is supplied from. That is, even when the gas is supplied from one ring-shaped gas ejection groove as in the present invention, the in-plane uniformity of the plasma processing can be sufficiently ensured.

In this embodiment, only one gas ejection groove is provided. However, the present invention is not limited to this. A plurality of gas ejection grooves may be provided concentrically. Further, here, the configuration is such that high-frequency power for plasma generation is applied to the mounting table 30, but
The configuration is not limited to this, and a configuration in which voltage is applied to the upper electrode or both the upper and lower electrodes may be adopted. Furthermore, an apparatus having a structure without the rotating magnet 66 may be used, and the mode of the plasma generation mechanism is not limited. Further, the gas supply head section has a three-part structure, but the number is not limited to this, and the form of the gas passage is not limited to a radial form, and any form may be adopted. In addition, although the description has been given by taking the plasma etching apparatus as an example, the present invention can be applied to other plasma processing apparatuses such as an ashing apparatus, a CVD apparatus, and a sputtering apparatus.

[0031]

As described above, according to the plasma processing apparatus of the present invention, the following excellent operational effects can be exhibited. Since the ring-shaped gas ejection groove is provided on the lower surface of the gas supply head portion and the surface defining the opening is curved, the electric field concentration of plasma can be reduced. For this reason, the peeling of the member surface due to the plasma sputtering can be suppressed, so that the generation of particles can be suppressed and the product yield can be improved. In addition, the life of the member can be prolonged because the separation due to spatter can be suppressed. In particular, by configuring the gas supply head unit with a plurality of members, only the damaged member needs to be replaced, and the maintenance cost is also reduced. Can be reduced. Further, by configuring the gas supply head section with a plurality of members, it is possible to easily perform a curved surface processing of a corner portion of each member. Further, the ring groove forming member is divided into a plurality of parts and is urged by a thermal expansion allowable elastic member, so that the thermal expansion of the member can be permitted while improving the mounting accuracy, and the width of the gas ejection groove is always designed. Can be maintained at the same predetermined value, and the gas flow rate can be made uniform. Further, by providing a plurality of gas ejection grooves concentrically, the in-plane uniformity of the plasma processing can be further improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional configuration diagram showing a plasma processing apparatus of the present invention.

FIG. 2 is an enlarged sectional view showing a gas supply head section of the apparatus shown in FIG.

FIG. 3 is a bottom view of the head unit shown in FIG. 2;

FIG. 4 is a partial cross-sectional side view showing a head main body of a gas supply head unit.

FIG. 5 is a plan view of a head main body.

FIG. 6 is a partial cross-sectional side view showing a ring groove forming member of the gas supply head unit.

FIG. 7 is a plan view of a ring groove forming member.

FIG. 8 is a sectional view showing a holding member of the gas supply head unit.

FIG. 9 is an enlarged sectional view showing a mounting portion of a ring groove forming member.

FIG. 10 is a graph showing the evaluation of the etching rate of the apparatus of the present invention and the conventional apparatus.

FIG. 11 is a schematic configuration diagram showing a conventional plasma processing apparatus.

FIG. 12 is an enlarged sectional view showing a shower head section of the apparatus shown in FIG.

13 is a bottom view of the head unit shown in FIG.

FIG. 14 is an enlarged view showing gas ejection holes of the head unit shown in FIG.

[Explanation of symbols]

 Reference Signs List 24 plasma processing apparatus 26 processing container 30 mounting table 42 high-frequency power supply 48 gas supply head unit 50 gas ejection groove 74 head body 76 ring groove forming member 78 holding member 84, 88 gas supply groove 90 gas passage 106 thermal expansion allowable elastic member W Processing object (semiconductor wafer)

Continuation of the front page (56) References JP-A-61-208222 (JP, A) JP-A-5-299382 (JP, A) JP-A-9-186140 (JP, A) US Patent 4612077 (US, A) (58) Field surveyed (Int.Cl. ⁷ , DB name) H01L 21/3065 C23C 14/34 C23C 16/50 C23F 4/00 H01L 21/205

Claims (7)

(57) [Claims] 1. A processing container capable of being evacuated, a mounting table mounted on the processing container for mounting an object to be processed, and a processing table for supplying a processing gas, the processing container being opposed to the mounting table. In a plasma processing apparatus having a gas supply head section and a high-frequency power supply for supplying high-frequency power for generating plasma in the processing container, the gas supply head section has a circular lower surface and has an inner peripheral end from its center. Toward
Head body having a gas passage formed therein, and disposed along the circumferential direction at a lower outer peripheral end of the head body.
Ring-shaped gas between the outer peripheral end of the head body
A ring groove forming member for forming an ejection groove; and a head body and a ring groove forming member disposed on the outer periphery of the ring groove forming member.
Holding unit for holding them on the ceiling of the processing container
More becomes wood, pre-cut ring-shaped with a surface defining an opening for forming a gas injection groove formed to have a curved surface, the ring-shaped
A plasma processing apparatus , wherein the ring groove forming member is divided into a plurality . 2. A plasma processing apparatus according to claim 1, wherein the thermal expansion allowable elastic member is interposed between the holding member and the ring groove forming member. 3. The outer peripheral end of the lower end of the head body and the inner peripheral end of the lower end of the ring groove forming member that define a ring-shaped opening of the gas ejection groove are formed into a curved surface. 3. The plasma processing apparatus according to 1 or 2 . Wherein said ring-shaped ring groove forming member, the plasma processing apparatus according to claim 1 to 3 further characterized in that is constituted by a ceramic material. 5. When the number of the ring-shaped gas ejection grooves is one, the diameter is set substantially equal to the radius of the object to be processed, and the center thereof is located on the center of the mounting table. the plasma processing apparatus according to claim 1 to 4, wherein. Wherein said gas injection groove, the plasma processing apparatus 1 to 4, wherein a is more concentrically formed. 7. A processing container capable of being evacuated,
A mounting table for mounting an object to be processed, which is accommodated in the processing container
And facing the mounting table to supply the processing gas. Let me
With the gas supply head arranged,
And a high-frequency power supply that supplies high-frequency power
In a plasma processing apparatus that The gas supply head has a circular bottom surface
A gas passage is formed from the center to the outer end.
Head body and the lower peripheral edge of the head body in the circumferential direction.
Along the outer peripheral end of the head body.
A ring groove forming member forming a gas-shaped gas ejection groove;
Located on the outer periphery of the head body and the ring groove forming member
A holding member for holding these on the ceiling of the processing container
Interposed between the ring groove forming member and the holding member
And the ring groove forming member is repelled toward the head main body.
Consisting of a thermally expandable elastic member that biases The ring groove forming member and the thermal expansion allowable elastic member
The link is formed by engaging the head body with each other.
The width of the gas-shaped gas ejection groove is regulated to a predetermined value.
And a plasma processing apparatus.