JPH10132141A - Conductance adjusting valve and semiconductor manufacturing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrain the strong exhaust flow from being generated in a change of conductance, by smooth and high-precise control of conductance. SOLUTION: A conductance adjusting valve 10 provided on an exhaust passage 9 is provided with a valve body 11 composed of large-diameter disc parts 11 and small-diameter curved surface parts 1b. When a rotary shaft 12a is operated in a direction to increase the opening (the conductance) after being rotated from the minimum conductance (full closing) state formed by the largediameter discs 11a, the clearance between the small-diameter curved surface parts 11b and the inside diameter of the exhaust passage 9 is a little increased according to a change of unit rotation angle of the rotary shaft 12a. Conductance to be controlled by the valve body 11 is slowly changed so as to be gradually increased from the minimum value, and formation of the sudden exhaust flow in the exhaust passage 9 is avoided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conductance adjusting technique and a semiconductor manufacturing technique, and more particularly to a technique which is effective when applied to a semiconductor manufacturing apparatus which performs pressure control by evacuation.

[0002]

2. Description of the Related Art For example, in a semiconductor device manufacturing process, there are many steps involving evacuation. For example, in a low-pressure thin film forming apparatus for forming a WSi ₂ thin film on a semiconductor wafer (hereinafter simply referred to as a wafer), a process chamber is evacuated to a desired degree of vacuum by a vacuum pump connected via a conductance adjusting valve. A reaction gas atmosphere is formed under reduced pressure, and a thin film is formed on the wafer on the susceptor using thermal energy. Then, in preparation for opening the inside of the process chamber, the degree of opening (conductance) of the conductance adjusting valve is increased, and the chamber is evacuated to a high vacuum that can be reached by a vacuum pump, thereby removing and purifying the reaction gas to form a thin film. The completed wafer is transferred out of the process chamber by the transfer arm.

Conventionally, as a structure of a conductance adjusting valve, for example, Nikkei McGraw-Hill, Showa 6
Published on June 20, 2000, "MOS LSI Manufacturing Technology" P1
26, etc. are also known. That is, as shown in FIG. 19, a structure in which a conductance is adjusted by rotating a rotation shaft 102 of a plate-shaped valve element 101 arranged so as to block an exhaust passage 100 is known.

[0004]

In the above prior art, after forming a thin film on a wafer at a pressure of, for example, about 600 Pa,
Further, when a thin film is formed on the wafer at a pressure of about 100 Pa, and then the conductance adjusting valve is opened to evacuate the process chamber to the ultimate pressure, a strong exhaust flow is formed due to a sudden change in conductance.
A phenomenon occurs in which components such as the wafer, susceptor, and shield ring in the process chamber oscillate.
There is a technical problem that there is a concern that foreign matter or the like scattered from the oscillating component adheres to the wafer to cause a defect, or the wafer is displaced to cause a failure in a transport system.

[0005] In order to prevent the swing during the evacuation, for example, it is conceivable to reduce the pressure stepwise by several tens Pa to a pressure at which the wafer, susceptor, shield ring and the like in the chamber do not swing. However, the processing time per wafer becomes longer, the number of processed wafers per unit time (throughput) of the low-pressure thin film forming apparatus decreases, and the program for controlling the opening of the conductance adjusting valve becomes complicated. Technical problems occur.

SUMMARY OF THE INVENTION An object of the present invention is to provide a conductance adjustment technique capable of suppressing the generation of a strong exhaust flow when the conductance changes by controlling the conductance smoothly and accurately.

Another object of the present invention is to provide a conductance adjustment which can suppress the generation of a strong exhaust flow when the conductance is changed by controlling the conductance smoothly and accurately without requiring a complicated control operation. To provide technology.

Another object of the present invention is to reduce the time required to reach a high degree of vacuum while suppressing the generation of a strong exhaust flow at the time of a change in conductance without requiring a complicated control operation. It is to provide a conductance adjustment technique.

Another object of the present invention is to provide a semiconductor manufacturing technique capable of evacuating to a high degree of vacuum in a short time without forming a strong exhaust flow that causes foreign matters and transport obstacles in a process chamber. To provide.

Another object of the present invention is to improve the yield by suppressing the occurrence of foreign matter, transfer troubles and the like in the process chamber,
An object of the present invention is to provide a semiconductor manufacturing technique capable of realizing an improvement in throughput by shortening a time required to reach a high degree of vacuum in a process chamber.

Another object of the present invention is to provide a semiconductor manufacturing technique capable of achieving both the formation of a thin film with good film quality and the improvement of throughput.

The above and other objects and novel features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

[0013]

SUMMARY OF THE INVENTION Among the inventions disclosed in the present application, the outline of a representative one will be briefly described.
It is as follows.

According to the present invention, there is provided a conductance adjusting valve having a valve body for controlling the conductance of an installed exhaust flow path, wherein the valve body includes a first portion for controlling the conductance constant in a fully closed state, and a fully closed state. And a second portion for gradually changing the conductance according to the degree of opening from the state.

Further, according to the present invention, there is provided a process chamber in which an object to be processed is accommodated, gas supply means for supplying a reaction gas to the process chamber, and an exhaust operation of the process chamber connected to the process chamber via an exhaust passage. In a semiconductor manufacturing apparatus including a vacuum pump for performing the above, and a conductance adjusting valve interposed in the exhaust flow path and controlling the conductance of the exhaust flow path, the conductance adjusting valve controls the conductance constant in a fully closed state. A valve body comprising a first part and a second part that gradually changes the conductance according to the degree of opening from the fully closed state.

According to the present invention described above, when the conductance adjusting valve is opened from the state of the minimum conductance (fully closed state) by the first part, the conductance is controlled by the second part for a fixed time or a constant conductance. Since the conductance can be controlled to increase, the airflow and the pressure difference between the upper and lower parts of the wafer cause the components such as the wafer, the susceptor and the shield ring to sway and scatter foreign matter, and the yield is reduced due to the adhesion of the foreign matter to the wafer. In addition to suppressing the drop, a transfer failure due to a wafer position shift or the like is also prevented, and the throughput can be improved by shortening the time required to reach a high vacuum.

[0017]

Embodiments of the present invention will be described below in detail with reference to the drawings.

(Embodiment 1) FIG. 1 is a sectional view showing an example of the configuration of a conductance adjusting valve according to a first embodiment of the present invention. FIG. 2 is a sectional view taken along line II-II in FIG. It is sectional drawing of a part. FIG. 3 is a conceptual diagram showing an example of a configuration of a semiconductor manufacturing apparatus according to an embodiment of the present invention. In this embodiment, a case where the present invention is applied to a low-voltage thin film forming apparatus as an example of a semiconductor manufacturing apparatus will be described.

First, a semiconductor manufacturing apparatus according to the present embodiment will be described with reference to FIG. The low-pressure thin-film forming apparatus according to the present embodiment is connected to the process chamber 3 via the load lock module 1, the transfer module 2, the process chamber 3, the process gas supply unit 4, the lamp heater 5, the exhaust passage 9, and the conductance adjusting valve 10. It is composed of a connected exhaust pump 6, a control unit 7, and the like. A susceptor 16 on which a wafer 17 is placed and a shield ring 13 surrounding the susceptor 16 are provided in the process chamber 3.

The exhaust pump 6 is for reducing the pressure inside the process chamber 3 and making the concentration distribution of the reaction gas therein uniform so that the film formed on the wafer 17 is made uniform. The pressure inside the process chamber is detected by the vacuum gauge 8 arranged in the process chamber 3, and the opening of the valve element 11 in the conductance adjusting valve 10 is automatically controlled by the control unit 7 so that the target pressure is maintained. Thus, the pressure inside the process chamber 3 is controlled. The control unit 7 also has a mechanism for controlling the heat treatment time, the flow rate of the reaction gas, the transfer of the wafer, and the like regarding the thin film formation. The wafer 17 is transferred from the cassette 15 in the load lock module 1 onto the susceptor 16 by the transfer arm 14. The wafer 17 transferred onto the susceptor 16 is heated to a certain temperature by the lamp heater 5. When the formation of the thin film is completed, the wafer 17 is collected in the cassette 15.

As shown in FIGS. 1 and 2, the conductance adjusting valve 10 mounted on the semiconductor manufacturing apparatus of the present embodiment has a diameter 2rc slightly smaller than the exhaust passage 9 having a diameter 2rd. And a valve body 11 having a disk portion 11a for controlling pressure at the time of forming a thin film, and a curved surface portion 11b for smoothly increasing conductance. This valve body 11
Is connected to a valve body rotation drive motor 12 whose rotation angle is controlled in response to a signal from the control unit 7 via a rotation shaft 12a. The conductance is adjusted.

In the case of the present embodiment, the dimensions of the curved surface portion 11b are such that the diameter near the disk portion 11a is 2 rb and the diameter of the disk portion 11b is 2 rb.
The aperture at a position distant from a is 2ra (ra ≦ rb). That is, the magnitude relation between the dimensions of the valve element 11 in the conductance adjusting valve 10 of the present embodiment is as follows: ra ≦ rb, rb <rc, rc <rd, 0 ° ≦ θ ≦ 90
°. When ra = rb, when the valve body is opened (clockwise rotation), a substantially constant conductance can be maintained for a certain time.

FIG. 5 is a diagram showing an example of the characteristic of the conductance adjusting valve 10 in this embodiment in comparison with the characteristic of the conventional configuration illustrated in FIG.

That is, in the conductance adjusting valve 10 of the present embodiment, when fully closed as illustrated in FIG. 1, the difference between the inner diameter of the exhaust passage 9 and the diameter of the disk portion 11a (2rd-2r
A constant conductance determined by the gap c) is obtained. On the other hand, for example, when the valve element 11 is rotated clockwise at the time of evacuation or the like, a substantially constant conductance can be maintained for a certain period of time. The change in conductance per degree of opening is extremely gentle as compared with the conventional configuration.

Hereinafter, an example of the operation of the low-pressure thin-film forming apparatus and the conductance adjusting valve 10 of the present embodiment will be described.

First, when the inside of the process chamber 3 is evacuated to reach a target vacuum degree of about 600 Pa, the conductance adjusting valve 10 is closed as shown in FIG. 600
While maintaining a degree of vacuum of about Pa, in this state, the process gas supply unit 4 supplies a predetermined time, for example, SiH ₂ Cl.
₂ and WF ₆ are supplied to form a WSi ₂ thin film on the wafer 17. At this time, make WF ₆ relatively small,
Form a Si-rich thin film.

Thereafter, the conductance adjusting valve 10 is opened to increase the conductance, thereby reducing the pressure in the process chamber 3 to about 100 Pa. In this state, a thin film is further formed. At this time, S
supplying i H ₂ Cl ₂ and WF _6. As described above, after forming a Si-rich film at a relatively high atmospheric gas pressure of about 600 Pa, a normal thin film is formed at 100 Pa, so that a WSi ₂ thin film having extremely good film quality is formed on the wafer 17. Can be formed on the wafer 17.

After the formation of the thin film, the process chamber 3
In order to clean the inside, the conductance adjusting valve 10 is opened (the valve body 11 rotates clockwise) so that the inside of the process chamber 3 is evacuated to the maximum vacuum achievable by the capacity of the exhaust pump 6.

Here, when the pressure is reduced from 600 Pa to 100 Pa for the stepwise control of the thin film forming pressure as described above, the conductance of the conventional conductance adjusting valve having the structure illustrated in FIG. At this time, since the pressure in the process chamber 3 drops at a stroke of 100 Pa or less, a sudden air flow and a pressure difference between the upper and lower sides of the susceptor 16 occur in the process chamber 3, and the wafer 17 and the susceptor 1
6, severe shaking of the shield ring 13 occurs. When this phenomenon occurs, the foreign matter that has rolled up adheres to the wafer 17 and causes the wafer 17 to have poor quality. Also,
There is a concern that the wafer 17 may be displaced on the susceptor 16 due to the shaking, causing a transfer trouble, and a complicated and long-time countermeasure such as a profile described later is required.

On the other hand, as shown in a profile to be described later, in the conductance adjusting valve 10 of the present embodiment, a high pressure is set so as to shift from a completely closed state during thin film formation under a vacuum of about 600 Pa to 100 Pa. Even if the valve element 11 is opened at a relatively high speed for a short period of time for evacuation, the conductance gradually increases, so that no violent airflow is formed in the process chamber 3. This eliminates concerns such as the occurrence of quality defects due to the adhesion of the foreign matter, and the occurrence of misalignment of the wafer 17 on the susceptor 16 resulting in transport trouble.

Referring to the diagram of FIG. 4, the above-described differences between the present invention and the prior art are illustrated in further detail. 600
In order to prevent the swing of the wafer 17, the susceptor 16, the shield ring 13 and the like when the process chamber 3 is evacuated from Pa to about 100 Pa, an exhaust control method such as the profile shown in FIG. .

Is a method of reducing the pressure by 25 Pa every 6 seconds. In the conventional conductance adjusting valve as shown in FIG. 19, when the pressure is reduced with a pressure width larger than this, a swing occurs. Also, shaking occurs even if it is less than 6 seconds. After the valve element 101 opens too much, the conductance increases, so that the conductance further increases. For this reason, it is not possible to completely prevent the parts from swinging. Approximately 6 seconds are required as the stabilization time per 25 Pa reduction, and the processing time for one wafer is 6 minutes and 45 seconds because the entire pressure reduction requires 2 minutes.

In the conventional conductance adjusting valve shown in FIG. 19, the opening degree of the valve element 101 is increased by 1 or 2 °. In this method, 600Pa to 100Pa
It takes 5 minutes to reduce the pressure, and the processing time for one wafer requires 9 minutes and 45 seconds. Further, when the valve body is opened at a constant angle, the conductance cannot be increased steadily with the conventional shape of the valve body, but sharply increases. Therefore, high-precision speed control of the opening is required, and in order to perform this opening control, complicated software and hardware are required for the control unit 7.

FIG. 3 shows a case where the conductance adjusting valve 10 of the present embodiment is used. The time required to reduce the pressure from 600 Pa to 100 Pa without generating the above-mentioned sway is 1 minute at the maximum (20 seconds at the minimum).
The processing time for a sheet is 5 minutes and 45 seconds. That is, the required time can be reduced by about 15% for the method and about 41% for the method. The reason why the pressure can be reduced in such a short time is that the valve body 11 has the disk portion 11a and the curved surface portion 11a.
b, the conductance is slightly increased from the fully closed state, so that even if the valve element 11 is opened at a constant speed, a sudden increase in conductance does not occur. This is because a stepwise pressure drop control and a highly accurate opening control as in the above are not required.

As described above, according to the conductance adjusting valve 10 and the low-pressure thin-film forming apparatus of the present embodiment, 600
When a thin film is formed on the wafer 17 at a pressure of about Pa, and the inside of the process chamber 3 is evacuated to the ultimate pressure after the formation of the thin film, the wafer 17, the susceptor 16 and the shield ring 13 shake due to a sudden change in pressure and airflow. Can be prevented. Accordingly, it is possible to prevent the generation of foreign matter due to the swing of the component and the defective quality of the wafer 17 due to the adhesion of the foreign matter. Further, since it is not necessary to take a long-time measure such as gradually reducing the pressure by several tens of Pa to a pressure at which the parts do not swing,
The processing capability of the low-pressure thin film forming apparatus is improved.

Further, since complicated valve opening control such as changing the opening little by little is not required, complicated opening control of the conductance adjusting valve 10 by software is not required, and the above-mentioned effect can be obtained simply and inexpensively. be able to.

Therefore, a relatively high reaction gas pressure of about 600 Pa and a low reaction gas pressure of about 100 Pa
The realization of good film quality by the film formation at the stage and the maintenance and improvement of the throughput can both be achieved, and the productivity of the semiconductor device manufacturing process is greatly improved.

When a thin film is formed in two stages of 600 Pa and 100 Pa, the thin film may be formed at 600 Pa, evacuated once to a high vacuum, and then formed at 100 Pa. In this case, the reaction gas at 600 Pa is completely eliminated, and the inside of the chamber can be cleaned, so that a thin film having better film quality can be obtained.

(Embodiment 2) FIG. 6 is a sectional view showing an example of the configuration of a conductance adjusting valve according to a second embodiment of the present invention. FIG. 7 is a sectional view taken along line VII-VII in FIG.
It is sectional drawing of the part.

The conductance adjusting valve 20 according to the second embodiment has a curved valve body 21 that enables constant pressure control and smooth conductance increase control when forming a thin film.

That is, the conductance adjusting valve 20
The inner diameter of the exhaust passage 9 is set to 2r
c, when the diameter of the maximum diameter portion 21a when fully closed is 2 rb, and the diameter of the curved surface portion 21b at an opening angle of only the angle θ is 2 ra, the following is satisfied: ra <rb, rb <rc, 0 ° ≦ θ ≦ 90 ° To do.

As a result, even if the curved valve element 21 is opened at a constant speed from the state where the conductance is minimum, the conductance does not increase sharply, so that the first example shown in FIG.
The same effect as that of the embodiment can be obtained.

(Embodiment 3) FIG. 8 is a sectional view showing an example of the configuration of a conductance adjusting valve according to a third embodiment of the present invention. FIG. 9 is a sectional view taken along line IX-IX in FIG. FIG. 10 is a sectional view of a portion taken along line XX in FIG.

The conductance adjusting valve 30 according to the third embodiment has a curved valve element 31 which enables constant pressure control and smooth conductance increase control when forming a thin film.

That is, the conductance adjusting valve 30
The inner diameter of the exhaust passage 9 is set to 2r
c, when the diameter of the maximum diameter portion 31a when fully closed is 2 rb, and the diameter of the curved surface portion 31b at the opening degree of the angle θ is 2 ra, the following is satisfied: ra <rb, rb <rc, 0 ° ≦ θ ≦ 90 ° To do.

As a result, even if the curved valve body 31 is opened at a constant speed from the state where the conductance is minimum, the conductance does not increase sharply, so that the first example shown in FIG.
The same effect as that of the embodiment can be obtained.

(Embodiment 4) FIG. 11 shows a fourth embodiment of the present invention.
FIG. 12 is a cross-sectional view showing an example of the configuration of the conductance adjusting valve according to the embodiment of the present invention.
FIG. 13 is a sectional view taken along line XI in FIG.
It is sectional drawing of the part of II-XIII.

The conductance adjusting valve 40 according to the fourth embodiment has a curved valve body 41 that enables constant pressure control and smooth conductance increase control during thin film formation.

That is, the conductance adjusting valve 40
The inner diameter of the exhaust passage 9 is set to 2r
c, when the diameter of the maximum diameter portion 41a when fully closed is 2 rb, and the diameter of the curved surface portion 41b at an opening degree of only the angle θ is 2ra, ra <rb, rb <rc, 0 ° ≦ θ ≦ 90 ° To do.

As a result, even if the curved valve element 41 is opened at a constant speed from the state where the conductance is minimum, the conductance does not increase sharply, so that the first example shown in FIG.
The same effect as that of the embodiment can be obtained.

(Embodiment 5) FIG. 14 shows a fifth embodiment of the present invention.
FIG. 15 is a cross-sectional view showing an example of the configuration of the conductance adjusting valve according to the embodiment of the present invention.
It is sectional drawing of the part of XV.

The conductance adjusting valve 50 of the fifth embodiment has a valve element 51 which enables constant pressure control and smooth conductance control during thin film formation.

That is, the conductance adjusting valve 50
The inner valve element 51 is composed of a large-diameter flapper 51a and a small-diameter flapper 51b. The dimensions of each part are as follows: the inner diameter of the exhaust passage 9 is 2rc, and the diameter of the large-diameter flapper 51a when fully closed is 2r.
b, when the diameter of the small-diameter flapper 51b which is displaced in the opening / closing direction by a predetermined angle is 2ra, the following relationship is satisfied: ra <rb, rb <rc, 0 ° ≦ θ ≦ 90 °.

As a result, even if the valve element 51 is opened at a constant speed from the state where the conductance is minimum, the conductance does not suddenly increase, so that the same effect as that of the first embodiment illustrated in FIG. Can be obtained.

(Embodiment 6) FIG. 16 shows a sixth embodiment of the present invention.
FIG. 17 is a cross-sectional view illustrating an example of the configuration of the conductance adjusting valve according to the embodiment of the present invention.
FIG. 18 is a sectional view taken along line XV in FIG.
It is sectional drawing of the part of III-XVIII.

The conductance adjusting valve 60 according to the sixth embodiment has a curved valve body 61 which enables constant pressure control and smooth conductance increase control when forming a thin film.

That is, the conductance adjusting valve 60
The inner diameter of the exhaust passage 9 is set to 2r
c, when the diameter of the maximum diameter portion 61a when fully closed is 2 rb, and the diameter of the curved surface portion 61b at an opening degree of only the angle θ is 2 ra, the following is satisfied: ra <rb, rb <rc, 0 ≦ θ ≦ 90 ° To do.

As a result, even if the curved valve body 61 is opened at a constant speed from the state where the conductance is minimum, the conductance does not increase sharply, so that the first example shown in FIG.
The same effect as that of the embodiment can be obtained.

Although the invention made by the present inventor has been specifically described based on the embodiments, the present invention is not limited to the above-described embodiments, and can be variously modified without departing from the gist thereof. Needless to say, there is.

For example, in the description of the above embodiment,
As an example, a case where the present invention is applied to a low-pressure thin film forming apparatus for forming a single-wafer WSi ₂ thin film has been described.
The present invention can be widely applied to apparatuses, plasma CVD apparatuses, diffusion apparatuses, batch-type apparatuses for batch-processing a plurality of wafers, and the like.

[0061]

Advantageous effects obtained by typical ones of the inventions disclosed in the present application will be briefly described.
It is as follows.

According to the conductance adjusting valve of the present invention,
The smooth and high-precision control of the conductance has the effect of suppressing the generation of a strong exhaust flow when the conductance changes.

Further, according to the conductance adjusting valve of the present invention, it is possible to suppress the generation of a strong exhaust flow at the time of a change in conductance by controlling the conductance smoothly and accurately without requiring a complicated control operation. it can,
The effect is obtained.

Further, according to the conductance adjusting valve of the present invention, it is possible to reduce the time required to reach a high degree of vacuum while suppressing the generation of a strong exhaust flow when the conductance changes without requiring a complicated control operation. Can be obtained.

According to the semiconductor manufacturing apparatus of the present invention, it is possible to evacuate to a high degree of vacuum in a short time without forming a strong exhaust flow that causes foreign matters and transport obstacles in the process chamber. Is obtained.

According to the semiconductor manufacturing apparatus of the present invention,
It is possible to obtain the effect of improving the yield by suppressing the occurrence of foreign matter and transfer obstacles in the process chamber, and improving the throughput by shortening the time required to reach a high vacuum in the process chamber.

According to the semiconductor manufacturing apparatus of the present invention,
The effect that both the formation of a thin film of good film quality and the improvement of the throughput can be achieved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of a configuration of a conductance adjusting valve according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a conceptual diagram illustrating an example of a configuration of a semiconductor manufacturing apparatus according to an embodiment of the present invention.

FIG. 4 is a diagram illustrating an example of the operation of the conductance adjusting valve and the semiconductor manufacturing apparatus of the present invention in comparison with the case of the related art.

FIG. 5 is a diagram showing an example of characteristics of a conductance adjusting valve of the present invention in contrast to characteristics of a conventional configuration.

FIG. 6 is a sectional view showing an example of a configuration of a conductance adjusting valve according to a second embodiment of the present invention.

FIG. 7 is a sectional view taken along line VII-VII in FIG. 6;

FIG. 8 is a sectional view showing an example of a configuration of a conductance adjusting valve according to a third embodiment of the present invention.

9 is a cross-sectional view taken along line IX-IX in FIG.

FIG. 10 is a sectional view taken along line XX in FIG. 8;

FIG. 11 is a sectional view showing an example of a configuration of a conductance adjusting valve according to a fourth embodiment of the present invention.

FIG. 12 is a sectional view taken along line XII-XII in FIG. 11;

FIG. 13 is a sectional view taken along line XIII-XIII in FIG. 11;

FIG. 14 is a sectional view showing an example of a configuration of a conductance adjusting valve according to a fifth embodiment of the present invention.

FIG. 15 is a sectional view taken along line XV-XV in FIG. 14;

FIG. 16 is a sectional view showing an example of a configuration of a conductance adjusting valve according to a sixth embodiment of the present invention.

FIG. 17 is a sectional view taken along line XVII-XVII in FIG. 16;

18 is a cross-sectional view taken along a line XVIII-XVIII in FIG.

FIG. 19 is a cross-sectional view showing an example of a configuration of a conventional conductance adjusting valve.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Load lock module 2 Transfer module 3 Process chamber 4 Process gas supply part 5 Lamp heater 6 Exhaust pump 7 Control part 8 Vacuum gauge 9 Exhaust flow path 10 Conductance adjustment valve 11 Valve body 11a Disk part (1st part) 11b Curved surface part (Second part) 12 Valve body rotation drive motor 12a Rotary shaft 13 Shield ring 14 Transfer arm 15 Cassette 16 Susceptor 17 Wafer 20 Conductance adjustment valve 21 Curved valve body 21a Maximum diameter part 21b Curved surface part 30 Conductance adjustment valve 31 Curved valve Body 31a Maximum diameter portion 31b Curved surface portion 40 Conductance adjustment valve 41 Curved surface valve member 41a Maximum diameter portion 41b Curved surface portion 50 Conductance adjustment valve 51 Valve body 51a Large diameter flapper 51b Small diameter flapper 60 Conductance adjustment valve 61 Curved surface valve 61a Maximum diameter part 61b Curved surface part

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Hiroshi Sakuma 2326 Imai, Ome-shi, Tokyo Inside the Hitachi, Ltd.Device Development Center (72) Inventor Min Tsang Fan United States, Texas 75248, Dallas, Lamanga, Texas Drive 6927

Claims (9)

[Claims] 1. A conductance adjusting valve having a valve body for controlling the conductance of an installed exhaust flow path,
The valve body includes a first portion that controls the conductance constant in a fully closed state, and a second portion that changes the conductance in accordance with an opening degree from the fully closed state. Conductance adjustment valve. 2. The conductance adjusting valve according to claim 1, wherein the valve element has a maximum diameter portion for controlling the conductance to a minimum by forming a predetermined fluid flow gap in the fully closed state; A conductance adjusting valve comprising: a curved surface portion that slightly increases the conductance according to an opening degree from a state. 3. The conductance adjusting valve according to claim 1, wherein the valve body forms a predetermined fluid flow gap in the fully closed state to control the conductance to be constant, and the fluid includes: A conductance adjusting valve, wherein a flow gap is fixed to at least one second flapper larger than the first flapper so as to intersect a rotation axis for driving the valve body. 4. The conductance adjustment valve according to claim 1, wherein the conductance adjustment valve is mounted on a semiconductor manufacturing apparatus in a semiconductor device manufacturing process. 5. A process chamber accommodating an object to be processed, gas supply means for supplying a reaction gas to the process chamber, and an exhaust passage connected to the process chamber through an exhaust flow path. A semiconductor pump including a vacuum pump to be performed and a conductance adjusting valve interposed in the exhaust flow path and controlling the conductance of the exhaust flow path, wherein the conductance adjusting valve keeps the conductance constant in a fully closed state. And a second part for changing the conductance in accordance with the degree of opening from the fully closed state.
A semiconductor manufacturing apparatus comprising a valve body comprising: 6. The semiconductor manufacturing apparatus according to claim 5, wherein the valve body of the conductance adjusting valve forms a predetermined fluid flow gap in the fully closed state to control the conductance to be constant. And a curved portion that slightly increases the conductance according to the degree of opening from the fully closed state. 7. The semiconductor manufacturing apparatus according to claim 5, wherein the valve body of the conductance adjusting valve forms a predetermined fluid flow gap in the fully closed state to control the conductance constant. A semiconductor manufacturing apparatus, wherein a flapper and at least one second flapper having a larger fluid flow gap than the first flapper are fixed so as to intersect a rotation axis for driving the valve element. 8. The semiconductor manufacturing apparatus according to claim 5, wherein the conductance adjusting valve is fully closed to reduce the conductance of the exhaust passage to a small and constant value, thereby suppressing exhaust in the process chamber. A first step of forming a thin film on the object by supplying the reaction gas while maintaining the inside of the process chamber at a relatively high pressure, and according to an opening degree of the valve body from the fully closed state. By slightly increasing the conductance,
A thin film forming process including a second step of forming a thin film under a lower pressure than the first step and a third step of evacuating the process chamber to a high vacuum and removing the reactive gas is performed. A semiconductor manufacturing apparatus characterized by the above-mentioned. 9. The semiconductor manufacturing apparatus according to claim 8, wherein the reaction gas comprises SiH ₂ Cl ₂ and WF ₆ , and in the first step, the WF ₆ is relatively compressed under a pressure of about 600 pa. A thin film of WSi ₂ is formed in a reduced state, and in the second step, almost 100 P
The thin film is formed by supplying the SiH ₂ Cl ₂ and WF ₆ under the pressure of a, and in the third step, the process chamber is evacuated to the ultimate degree of vacuum possible by the evacuation capacity of the vacuum pump. A semiconductor manufacturing apparatus characterized by the above-mentioned.