JP2002327274A - Film forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a film forming apparatus which can turn the temperature of a shower head into a desirable one in a short time, and has high temperature- stability at the shower head. SOLUTION: This apparatus comprises a chamber 2 for forming a film on a substrate W to be treated, a mounting table 3 for mounting the substrate W in the chamber 2, a shower head 10 having many gas discharge holes arranged so as to face the table 3, a gas feeding mechanism 30 for supplying a treatment gas in the chamber 2 through the shower head 10, and a temperature control means 60 for controlling a temperature of the shower head 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to chemical vapor deposition (CV).
The present invention relates to a film forming apparatus for forming a predetermined thin film on a substrate to be processed by D).

[0002]

2. Description of the Related Art In a semiconductor manufacturing process, Ti, Al, Cu are used for filling holes between wirings formed in a semiconductor wafer to be processed or as a barrier layer.
And a metal compound such as WSi, TiN, and TiSi are deposited to form a thin film.

Conventionally, thin films of these metals and metal compounds have been formed by physical vapor deposition (PVD). Recently, however, there has been a particularly demand for miniaturization and high integration of devices, and design rules have become particularly strict. Therefore, it is difficult to obtain sufficient characteristics with PVD having poor embedding properties. Therefore, such a thin film is formed by CVD which can be expected to form a higher quality film.

In a conventional CVD film forming apparatus, for example, a film forming apparatus for forming a Ti film, a semiconductor wafer mounting stage in which a heater is built in a chamber having a heater, and a processing gas discharge facing the upper side of the stage. A shower head for heating, the chamber is heated to a predetermined temperature, the inside of the chamber is evacuated to a predetermined degree, and the semiconductor wafer on the stage is heated to a predetermined temperature while the TiCl ₄ , H _2, etc. Is supplied, and high-frequency power is supplied to the shower head to convert these gases into plasma to form a film.

[0005]

However, recently,
Because semiconductor wafers are getting larger at 300mm,
It is necessary to increase the size of such a film forming apparatus, and accordingly, the following problems have become apparent.

That is, the shower head provided opposite to the stage is heated by radiant heat when the temperature of the heater in the stage is increased. The heat capacity is large, and it takes a long time for the temperature to stabilize when the temperature rises.
That is, the throughput deteriorates. On the other hand, if the treatment is performed without the temperature of the showerhead, particularly the temperature of the surface of the showerhead being unstable, uniform treatment cannot be performed. Further, the conventional shower head has a structure with high heat insulation in order to secure temperature stability during processing. For example, it takes an extremely long time to lower the temperature to a predetermined temperature during cleaning. For this reason, it is conceivable to perform cleaning in a high temperature state. However, cleaning in a high temperature state may damage the shower head member.

Conventionally, when plasma processing is performed, the temperature of members in the chamber rises due to the plasma. In particular, the temperature of the showerhead surface is likely to increase due to the large area exposed to plasma facing the wafer surface. However, if a film is formed after idling or cleaning, the film formation rate may be low when the first wafer is formed. This is because the temperature of the showerhead is about 500 ° C. during normal film formation and 470 to 480 ° C. and 20 to 30 ° C.
The cause is probably low. Therefore, it is necessary to set the stage temperature to a temperature higher than the temperature at the time of film formation.

Further, conventionally, when performing maintenance of the shower head, the upper cover including the shower head is opened at an angle of 90 ° or less, and then maintenance such as removal of the shower head is performed due to limitations of the apparatus. When the size of the shower head is increased and the weight is increased with the increase in the size of the apparatus, it is difficult to perform maintenance of the shower head by such a method.

The present invention has been made in view of such circumstances, and provides a film forming apparatus that can bring a shower head to a desired temperature in a short time and has high temperature stability of the shower head. Further, it is an object of the present invention to provide a film forming apparatus having high maintainability of a shower head.

[0010]

In order to solve the above-mentioned problems, the present invention provides a chamber for forming a film on a substrate to be processed, a mounting table for mounting the substrate in the chamber, and a mounting table. Shower head having a large number of gas discharge holes provided opposite to each other, a gas supply mechanism for supplying a processing gas into the chamber via the shower head, and a shower head temperature control means for controlling the temperature of the shower head And a film forming apparatus comprising: In this case, it is preferable that the chamber is configured to be able to be evacuated.

Further, the present invention provides a chamber for forming a film on a substrate to be processed in a vacuum atmosphere, a mounting table on which the substrate is mounted in the chamber, and a plurality of substrates provided opposite the mounting table. A shower head having a gas discharge hole, a gas supply mechanism for supplying a processing gas into the chamber via the shower head, and a shower head temperature control unit for controlling a temperature of the shower head, wherein the shower head is A chamber inside the chamber including the gas discharge hole forming surface, and an atmosphere side outside the chamber, wherein the shower head temperature control means is provided on the atmosphere side of the chamber. There is provided a film forming apparatus characterized by being provided. In this case, it is preferable to provide a heating means for heating the chamber.

According to the present invention having the above-described structure, since the shower head is provided with the temperature control means, the radiation from the stage does not act dominantly when the shower head is heated, but the desired temperature is positively increased. , And the temperature can be raised and lowered in a short time even with a large-sized device. In addition, since the temperature of the shower head can be positively controlled as described above, the temperature stability of the shower head can be improved.

Further, for example, before processing the substrate to be processed,
When forming a pre-coat on a shower head, etc.
When a film is formed on a processing substrate,
But a stable film is deposited on the showerhead.
In addition, TiCl generated in the intermediate reaction _xNeed to be volatilized
Therefore, the shower head should be 425 ° C or more, preferably
Needs to be heated to 500 ° C. or higher. With conventional technology
It may take a long time to raise the temperature of the shower head,
It was unclear whether the pad was at the desired temperature
May not be able to produce a stable film,
-By providing temperature control means on the head, film formation,
Control the shower head to the desired temperature during pre-coating
A stable film can be reliably formed on the shower head
can do. And perform the first film formation stably
be able to.

Further, since the shower head is configured to have the atmosphere side portion and the temperature control means is provided in the atmosphere side portion, the temperature control means can be handled in the atmosphere, and the handling is easy.

In this case, it is preferable that the apparatus further comprises a mounting table heating means for heating the mounting table, and further comprises a chamber heating means for heating the chamber. Further, the showerhead temperature control means includes a heating mechanism for heating the showerhead, a cooling mechanism for cooling the showerhead, a temperature detection mechanism for detecting a temperature of the showerhead, and at least a temperature detection mechanism based on a detection result of the temperature detection mechanism. And a controller for controlling the heating mechanism. This makes it possible to quickly bring the shower head to a desired temperature in both cases of raising and lowering the temperature.

Further, the heating mechanism has an inner heater for heating an inner part of the shower head, and an outer heater for heating an outer part, and the temperature detecting mechanism has an inner heater for detecting a temperature of the inner part. A configuration may be provided that includes a temperature detection unit and an outside temperature detection unit that detects a temperature of the outside portion. Further, the controller controls the inner heater so that the temperature becomes a set temperature based on the detection value of the inner temperature detecting unit, and sets the detected temperature difference between the inner temperature detecting unit and the outer temperature detecting unit to zero. It can be configured to control the outer heater. With such a configuration, the dissipation of heat from the outer peripheral portion of the shower head can be suppressed, and more accurate temperature control can be realized.

[0017] It is possible to adopt a configuration in which a heat insulating material is provided facing the surface of the shower head opposite to the chamber. Thereby, heat dissipation from the shower head during the processing can be effectively suppressed.

[0018] The shower head may have a shower head body and an annular support portion continuous above the outer periphery of the shower head body, and the support portion may have a rib structure. This makes it possible to reduce the thickness of the portion other than the ribs of the support portion, and to reduce the dissipation of heat from the support portion, thereby further improving the temperature controllability.

Further, an annular filling member and a member for fixing the filling member are provided between the shower head and the wall surface of the chamber, and an elastic member is interposed between the filling member and the member for fixing the filling member. The configuration can be as follows. With this elastic member, the gap with the fixing member can be made uniform, and breakage can be prevented when, for example, quartz or ceramic is used for the filling member.
Further, the apparatus may further include a plasma generation unit for generating a plasma of the processing gas in the chamber.

According to another aspect of the present invention, there is provided a film forming apparatus provided with a chamber for forming a film on a substrate to be processed, a mounting table for mounting the substrate to be processed in the chamber, and a mounting table opposed to the mounting table. A shower head having a large number of gas discharge holes, a gas supply mechanism for supplying a processing gas into the chamber via the shower head, and a reversing mechanism for turning the shower head to the outside of the chamber and reversing the shower head. It is characterized by doing.

According to the film forming apparatus having such a configuration, since the shower head is turned to the outside of the chamber and turned over, the shower head can be almost completely outside the chamber, thereby maintaining the shower head. Can be performed very easily.

In this case, an annular filling member and a member for fixing the filling member are provided between the shower head and the wall surface of the chamber, and an elastic material is provided between the filling member and the member for fixing the filling member. Preferably, a member is interposed. Thereby, the gap between the elastic member and the fixing member can be equalized, and breakage can be prevented when, for example, quartz or ceramic is used for the filling member. Further, the fixing member can be detached outward with the shower head turned upside down, and the filling member can be detached upward after detaching the fixing member outward, and It is preferable that the configuration is such that maintenance of the shower head can be performed after the member is removed upward. Thus, the fixing member and the filling member can be easily removed, and the maintenance of the shower head can be performed more easily.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be specifically described below by taking a CVD film forming apparatus for forming a Ti thin film as an example.

FIG. 1 is a sectional view showing a CVD film forming apparatus for forming a Ti thin film according to an embodiment of the present invention, and FIG. 2 is a plan view showing an upper part of a shower head of the CVD film forming apparatus shown in FIG. . The CVD film forming apparatus 1 has a substantially cylindrical or box-shaped chamber 2 which is airtightly arranged, and includes a stage 3 for horizontally mounting a semiconductor wafer W as an object to be processed. Is provided. A stage holding member 7 protruding downward is attached to the center of the bottom of the chamber 2 via a seal ring, and a cylindrical member 4 joined to the stage 3 is attached to the stage holding member 7. The chamber 2 and the stage holding member 7 have a heating mechanism (not shown), and these are heated to a predetermined temperature by being supplied with power from a power supply (not shown).

At the outer edge of the stage 3, for example, a ring 5 for stabilizing the generation of plasma is provided. Further, a heater 6 is embedded in the stage 3, and the heater 6 is heated by a power source (not shown) to heat the semiconductor wafer W, which is an object to be processed, to a predetermined temperature.
Further, a mesh electrode 71 is provided above the heater 6 of the stage 3.

The stage 3 has three (two shown) wafer support pins 7 for supporting and raising and lowering the wafer W.
5 is provided so as to be able to protrude and retract from the surface of the stage 3, and these wafer support pins 75 are fixed to a support plate 76. The wafer support pins 75 are moved up and down via a support plate 76 by a drive mechanism 77 such as an air cylinder.

A loading / unloading port 73 for loading / unloading the wafer W and a gate valve 74 for opening / closing the loading / unloading port 73 are provided on the side wall of the chamber 2.

A shower head 10 is provided above the chamber 2 so as to face the stage 3. The shower head 10 has an upper plate 10a, a middle plate 10b, and a lower plate 10c, and has a circular planar shape.

The upper plate 10a is a middle plate 10
It has a horizontal portion 10d that constitutes the showerhead main body together with the b and the lower plate 10c, and an annular support portion 10e that is continuous above the outer periphery of the horizontal portion 10d, and is formed in a concave shape. FIG. 1 shows the inside of the support portion 10e.
As shown in FIG. 2, ribs 10f are arranged at equal intervals toward the center of the shower head 10. The thickness of the rib 10f is preferably 5 mm or more. This rib 10f
Is formed, the thermal deformation of the support portion 10e can be suppressed, the support strength can be increased, and the thickness of the support portion 10e can be reduced. Thereby, heat dissipation from the shower head 10 can be suppressed.

The upper plate 10a functions as a base member, and the upper portion of the outer periphery of the annularly formed concave middle plate 10b is screwed to the lower portion of the outer periphery of the horizontal portion 10d of the upper plate 10a. Also, the middle plate 10
The upper surface of the lower plate 10c is screwed to the lower surface of b. A space 11 is provided between the lower surface of the horizontal portion 10d of the upper plate 10a and the upper surface of the middle plate 10b having a concave portion.
a is formed airtight. A plurality of grooves are formed radially and uniformly on the lower surface of the middle plate 10b. The middle plate 10b and the lower plate 10c are also air-tightly joined, and a space 11b is formed between a plurality of grooves formed on the lower surface of the middle plate 10b and the upper surface of the lower plate 10c. In the middle plate 10b, a number of first gas passages 12a penetrating from the space 11a to the lower plate 10c through a plurality of holes formed in the middle plate 10b,
A second gas passage 12b is formed which does not communicate with the space 11a but communicates with the space 11b. Lower plate 10c
Are formed with a number of first gas discharge holes 13a communicating with the first gas passage 12a and a number of second gas discharge holes 13b communicating with the space 11b.

Here, the inner diameter of the first gas passage 12a formed in the middle plate 10b is, for example, φ0.5 to 3 m.
m, preferably 1.0 to 2.0 mm. The first gas discharge holes 13a formed in the lower plate 10c have a two-stage structure. The inner diameter of the first gas discharge holes 13a on the space 11a side is, for example, φ1 to 3.5 mm, preferably 1.2 to 2.3 mm.
And the opening side of the lower surface is, for example, φ0.3 to 1.0 m
m, preferably 0.5 to 0.7 mm.

A first gas inlet pipe 14a and a second gas inlet pipe 14b are connected to the upper surface of the upper plate 10a. The first gas introduction pipe 14a is connected to the space 11a.
The second gas introduction pipe 14b communicates with the second gas passage 12b of the middle plate 10b, and further communicates with the space 11b. Therefore, the gas introduced through the first gas introduction pipe 14a passes through the space 11a and the first gas passage 12a, is discharged from the first gas discharge hole 13a, and passes through the second gas introduction pipe 14b. The introduced gas is introduced into the space 11b through the second gas passage 12b, and is discharged from the second gas discharge hole 13b. That is, the shower head 10 is connected to the first gas introduction pipe 14a.
And the gas supplied via the second gas introduction pipe 14b are separately supplied into the chamber 2 so as not to be mixed in the shower head 10.

FIG. 3 is an enlarged view of the shower head 10 of FIG. As shown in FIGS. 1 and 3, a projection 10 g is formed on a portion of the upper surface of the upper plate 10 a including a connection portion with the second gas introduction pipe 14 b, and the upper plate 1
The lower surface of the portion corresponding to the convex portion 10g of Oa has a concave portion 10h.
Are formed. On the other hand, at a position corresponding to the second gas introduction tube 14b of the middle plate 10b, a tube portion 10j which protrudes upward from the upper surface thereof and has a second gas passage formed therein is integrally provided. At the upper end of the portion 10j, a flange portion 10i that fits into the recess 10h is integrally formed. In the recess 10h, the upper plate 1
A seal ring 10k is provided between the lower surface of Oa and the upper surface of the flange portion 10i. This makes it possible to more reliably prevent the respective gases supplied from the first gas introduction pipe 14a and the second gas introduction pipe 14b from being mixed.

FIG. 4 is a sectional view taken along the line AA in FIG.
FIG. 5 shows a cross-sectional view taken along line -B. As shown in FIGS. 3 and 4, the middle plate 10b and the lower plate 10c are fastened by bolts 101. The arrow in FIG. 5 indicates the general direction of the flow of the gas supplied from the second gas passage 12b into the space 11b. FIG. 5 shows a state in which a distal end portion of the pipe portion 10j connected to the second gas introduction pipe 14b has
As shown in FIG. 6, a pair of slit-like discharge ports 121 formed in a plane fan shape is provided, and the gas passing through the second gas passage 12b is supplied to these discharge ports 12b.
1 is discharged in the direction of the arrow. The opening degree of the flat fan-shaped discharge port 121 is determined by the first gas passage 12a.
It is preferable that the opening degree is smaller than 160 °, for example, so as not to communicate with the opening. As shown in FIG. 7, a plurality of holes (three on each side in FIG. 7) are used instead of the slit-shaped discharge ports 121.
May be provided. The arrangement of the holes at this time may be horizontal or vertical as shown. The hole is smaller than the second gas passage 12b,
The number may be one on each side.

On the other hand, as shown in FIG.
0a, the first and second gas introduction pipes 14a,
A flange 14 is welded to the other end of 14b. An insulating member 24 having a first gas passage 24a and a second gas passage 24b is connected to the flange 14. A gas introducing member 26 having a first gas passage 26a and a second gas passage 26b is connected to the other of the insulating member 24. The gas introduction member 26 is connected to the upper surface of the lid member 15. The lid member 15 and the chamber 2 have first gas passages 15a and 2a and second gas passages 15b and 2b, respectively.
A seal ring such as an O-ring is interposed in each of the gas passage connection portions up to the above. Further, the gas pipe 25a is connected to the first gas passage 2a of the chamber 2 by the gas pipe 25b.
Are connected to the second gas passage 2b. Gas piping 25
A gas supply unit 30 is connected to the other end of each of a and 25b.

The gas supply unit 30, the cleaning gas ClF ₃ gas source 31 for supplying ClF ₃ is, TiCl ₄ TiCl ₄ gas source 32 for supplying a film forming gas, Ar gas supplying Ar as a carrier gas source 33, NH ₃ gas source 35 for supplying NH ₃ to be used in the nitridation of the _{H 2} gas source 34 and the Ti film _{H 2} is supplied as a reducing gas
have. Gas pipes 36 and _{3 are provided to the} ClF ₃ gas source 31, the TiCl ₄ gas source 32, and the Ar
7, 38 are connected to these gas pipes 36, 3
7, 38 are connected to the gas pipe 25b. Also,
Gas pipes 39 and 40 are connected to the H ₂ gas source 34 and the NH ₃ gas source 35, respectively.
Reference numerals 9 and 40 are connected to a gas pipe 25a. Therefore, ClF ₃ gas source 31, TiCl ₄ gas source 32, Ar
The gas from the gas source 33 is supplied from the gas pipe 25b to the second gas passages 2b, 15b, 26b, and 24b of the above-described components.
Then, the gas passes through the gas introduction pipe 14b to reach the second gas passage 12b of the middle plate 10b of the shower head 10, and then is introduced into the space 11b, and the second gas passage 12b of the lower plate 10c
Is discharged from the gas discharge holes 13b. The gas from the H ₂ gas source 34 and the NH ₃ gas source 35 is supplied to the gas pipe 25a.
From the first gas passages 2a, 15a, 2
The gas is introduced into the space 11a of the shower head 10 through 6a, 24a and the gas introduction pipe 14a, and is discharged from the first gas discharge hole 13a of the lower plate 10c through the first gas passage 12a of the middle plate 10b. You. Therefore, during the film forming process, the TiCl ₄ gas and the H ₂ gas are not mixed during the gas supply, and
After being discharged into the semiconductor wafer W, they are mixed, plasma of these gases is formed, a desired reaction occurs, and a Ti film is formed on the semiconductor wafer W. Each of the gas pipes 36, 37, 38, 39, 40 from each gas source has a mass flow controller 41 and a pair of open / close valves 42, 43 provided so as to sandwich the mass flow controller.
Is provided. Although not shown here, the gas supply unit 30 includes an N ₂ gas source, other piping, an open / close valve, and the like. Further, by changing the gas source connected to the first gas passage 26a and the second gas passage 26b formed in the gas introduction member 26, the space 11a,
The gas supplied to 11b may be changed.

A lid member 15 having an opening is attached to the upper surface of the chamber 2, and an annular insulating member 16 is attached to an inner peripheral portion of the lid member 15. Then, the upper plate 1 is placed via an insulating member 16.
The support portion 10 e of the reference numeral 0 a is supported by the lid member 15. The upper part of the support part 10e is covered with an annular insulating member 21 for keeping heat, and the insulating member 21 is supported by the lid member 15. The insulating member 16 insulates between the shower head 10 and the chamber 2 and has a heat insulating effect.
Airtightness is maintained by interposing a seal ring such as an O-ring between the chamber 2 and the lid member 15, between the lid member 15 and the insulating member 16, and between the insulating member 16 and the support portion 10e. are doing.

On the upper surface of the horizontal portion 10d of the upper plate 10a, an inner heater 17 is disposed so as to correspond to the entire surface of the semiconductor wafer W on the stage 3. An annular (doughnut-shaped) outer heater 18 is fitted so as to surround the outside. The inner heater 17 is, for example,
It has a structure in which thin sheets on which heater wires are formed are sandwiched between a pair of mica insulating plates. The outer heater 18 is a sheath type in which an insulating material is disposed inside an outer tube and a heating element is provided inside the outer tube. In addition, as shown in FIG. 16 described later, the same heater as the inner heater can be used as the outer heater. These heaters function as components of a shower head temperature control unit described later.

An insulating plate 72 is provided between the inner heater 17 and the horizontal portion 10d of the upper plate 10a.
A space 19 is provided above the inner heater 17,
A heat insulating member 20 is provided thereon. Insulation member 2
Examples of 0 include ceramics such as Al ₂ O ₃ and resin materials. The heat insulating member 20 is provided in the cooling gas passage 2.
0a and a discharge port 20b, and a dry air supply pipe 61a for cooling inside is connected to an upper portion thereof. The dry air discharged from the pipe 61a is
To cool the inner heater 17 and its surroundings. Further, a dry air supply pipe 61b for outside cooling is disposed above the support portion 10e of the upper plate 10a. The pipe 61b is connected to a pipe 61c provided in an annular shape along the inner peripheral side of the insulating member 21, and a hole for discharging dry air downward is uniformly provided in the pipe 61c over the entire circumference. . The discharged dry air is supplied to the gap between the insulating member 16 and the heat insulating member 20 and its periphery, and cools the outer heater 18 and its periphery.

The upper plate 10a of the shower head 10
Is connected to a power supply rod 45 extending from above, and a high frequency power supply 47 is connected to the power supply rod 45 via a matching unit 46. And this high frequency power supply 47
The showerhead 10 is supplied with high-frequency electric power, whereby the processing gas supplied into the chamber 2 is turned into plasma by a high-frequency electric field formed between the showerhead 10 and the mesh electrode 71, thereby promoting a film forming reaction.

The upper plate 10a, the middle plate 10b, and the lower plate 1 around the lower part of the shower head 10.
Oc, a lower surface of the insulating member 16, a lower surface and side surfaces of the lid member 15, and a space surrounded by the side wall of the chamber 2 are formed of an annular quartz for preventing plasma from being formed. Filler 48 is fitted. As shown in FIG. 8, the filler 48 has a concave portion 48a on its outer portion.
The protrusions 49a of the plurality of support members 49 screwed to the lid member 15 are fitted into the recesses 48a to support the filler 48. Then, the side surface of the concave portion 48 a of the filler 48 and the convex portion 49 of the support member 49 are formed.
A plurality of elastic members 50 made of an elastic material such as fluoro rubber are interposed between the side surfaces of the elastic member 50a. This elastic member 50
, The shower head 10 can be easily centered, the attachment and detachment of the filler 48 can be simplified, and the filler 48 can be prevented from being damaged due to expansion and contraction due to heat. Also,
An elastic member 51 is also interposed between the filler 48 and the cover member 15, and this elastic member 51 also has a function of preventing the filler 48 from being damaged.

An exhaust pipe 52 is connected to the bottom side wall of the cylindrical stage holding member 7 attached to the bottom of the chamber 2, and an exhaust device 53 is connected to the exhaust pipe 52 to exhaust the inside of the chamber 2. It is supposed to. Although not shown, a device for capturing unreacted substances and by-products is provided upstream of the exhaust device 53. By operating the exhaust device 53, the pressure inside the chamber 2 can be reduced to a predetermined degree of vacuum. Further, the shield box 23 is provided on the lid member 15, and an exhaust port 54 is provided above the shield box 23.
Heat exhaust of the inner dry air and the outer dry air in the shield box 23 is performed from the exhaust port 54.

Further, the CVD film forming apparatus 1 according to this embodiment
Is provided with a showerhead temperature control means 60 for controlling the temperature of the showerhead 10. Hereinafter, the temperature control means 60 will be described in detail.

The shower head temperature control means 60
The temperature of the inner heater 17 and the outer heater 18 described above as a heating mechanism, the dry air supply pipes 61a and 61b for supplying dry air as a cooling mechanism, and the temperatures of the inner heater 17, the outer heater 18, and the lower plate 10c of the shower head 10 are detected. Thermocouples 65a, 65b,
66a, 66b and a controller 62 for controlling these
And

As shown in an enlarged manner in FIG. 9, a power supply 63 is connected to the inner heater 17 and the outer heater 18 is connected to the power source 63.
Is connected to a power supply 64. Further, thermocouples 65a and 65b for detecting temperatures near the inner heater 17 and inside the lower plate 10c are provided at positions corresponding to the inner heater 17 disposed inside the upper plate 10a of the shower head 10, respectively. Is provided. The thermocouple 65a penetrates through the inner heater 17, and its tip is located on the upper surface of the insulating plate 72, and the tip of the thermocouple 65b reaches the inside of the lower plate 10c. Also, the upper plate 10
Thermocouples 66a and 66b for detecting temperatures outside the upper plate 10a and outside the lower plate 10c, respectively, are provided at positions corresponding to the outer heaters 18 arranged on the outer peripheral side on the upper side a. Thermocouples 66a, 66
The tips of b reach the inside of the upper plate 10a and the lower plate 10c, respectively. These thermocouples 65a, 65
A plurality of b, 66a, 66b can be provided. Further, based on a command from the controller 62 and a detection signal from the thermocouple 65a or 65b, an inner temperature controller 67 that performs PID control on the output of the inner heater 17 to perform temperature adjustment.
And an outside temperature controller 68 that performs PID control of the output of the outside heater 18 based on a command from the controller 62 and a detection signal from the thermocouple 66a or 66b to perform temperature adjustment. These control the temperature of the shower head 10 during heating.

On the other hand, the dry air supplied from the dry air supply pipe 61a as the refrigerant is introduced into the space 19 through the cooling gas passage 20a of the heat insulating member 20, and is discharged from the inner heater 17 into the space 19. The heat is removed, and is discharged from the exhaust port 54 of the shield box 23 provided above the lid member 15 through the discharge port 20b. The dry air supplied to the dry air supply pipe 61b is supplied from a discharge hole below the pipe, takes heat from the outside of the shower head, and is discharged from the exhaust port 54 of the shield box 23. Dry air supply piping 6
1a and 61b are provided with air operation valves 69a and 69b, respectively.
2 controls.

Such a shower head temperature control means 6
At the time of heating using 0, preferable temperature control can be realized by controlling as shown in FIG. In the control of FIG. 10, a temperature is set in the controller 62, and the output of the inner heater 17 is controlled by the temperature controller 67 so that the detected temperature of the thermocouple 65a or 65b becomes the set temperature. The detected value of 65 b is output from the controller 62 to the temperature controller 68, and the detected temperature of the thermocouple 66 a or 66 b at a position corresponding to the outer heater 18 and the inner heater 17.
The temperature controller 68 controls the outer heater 1 so that the difference between the detected temperature of the thermocouple 65a or 65b corresponding to
8 is controlled. Thereby, the shower head 10
Is controlled so that the outer portion of the first portion has substantially the same temperature as the inner portion.

The upper surface of the upper plate 10a of the shower head 10 and its upper part are exposed to the atmosphere. That is, the thermocouples 65b and 66b of the shower head temperature control means 60 are arranged in the shower head 10 and are in a vacuum, but the other components are arranged in the atmosphere.

As shown in FIG.
Can be inverted to the outside of the chamber 2 by an inversion mechanism 80 composed of a hinge mechanism, whereby the shower head 10 can be almost completely turned upside down with its gas discharge surface facing upward, as shown in FIG. Since the shower head 10 can be present outside, maintenance of the shower head 10 can be performed extremely easily. Specifically, FIG.
In the state, the plurality of support members 49 can be easily removed first by removing the fixing screws (arrows), and when the support members 49 are removed, the filler 48 can be easily removed upward (arrows). ). When the filler 48 is removed, the maintenance of the shower head 10 can be easily performed. For example, the lower plate 10c and the middle plate 10b can be easily removed upward (arrows). Shower head 10
When reversing the angle, it is preferable that the shower head 10 be located at a position rotated by 180 degrees, but the angle may be in the vicinity thereof. In order to hold the shower head 10 at such an angle, for example, a gas spring or the like can be used.

Next, the processing operation of the CVD film forming apparatus 1 configured as described above will be described. First, prior to forming a Ti thin film on the semiconductor wafer W, a Ti precoat film is formed on the surface of the shower head 10, the stage 3, and the like in the following procedure. First, the surroundings of the chamber 2, the heater 6 of the stage 3, and the inside and outside heaters 17 and 18 of the shower head 10 are heated, and while the inside of the chamber 2 is exhausted by the exhaust device 53, a predetermined gas is supplied at a predetermined flow ratio. And the inside of the chamber 2 is set to a predetermined pressure. Next, a film forming gas including H ₂ gas, TiCl ₄ gas, and other gases is supplied into the chamber 2 at a predetermined flow rate, and high frequency power is supplied from the high frequency power supply 47 to the shower head 10 to generate plasma in the chamber 2. Then, a Ti film is formed on the surface of the shower head 10, the stage 3, and the like. Next, power supply of the high frequency power supply 47 and TiCl
The supply of the _four gases is stopped, NH ₃ gas and other gases are supplied at a predetermined flow rate, and high frequency power is again supplied from the high frequency power supply 47 to the shower head 10 to generate plasma, and the surface of the formed Ti film is formed. Is nitrided. This allows
A stable precoat film is formed on the surfaces of the shower head 10, the stage 3, and the like. After the end of the nitriding process, the power supply of the high-frequency power supply 47 and the supply of the NH ₃ gas are stopped.

After the completion of the precoating, the gate valve 74 is opened, the semiconductor wafer W is carried into the chamber 2, delivered to the protruding wafer support pins 75, and lowered to be mounted on the stage 3. . Next, H ₂ , TiCl ₄ gas, and other gases are supplied at a predetermined flow rate, high-frequency power is supplied from the high-frequency power supply 47 to the shower head 10 to generate plasma in the chamber 2, and a Ti film is formed on the semiconductor wafer W. Film. Next, the power supply of the high frequency power supply 47 and the supply of the TiCl ₄ gas are stopped, and NH ₃
Gas and other gases are supplied at a predetermined flow rate, and high frequency power is again supplied from the high frequency power supply 47 to the shower head 10 to generate plasma, and the Ti film formed on the semiconductor wafer W is nitrided. After the end of the nitriding process, the power supply of the high-frequency power supply 47 and the supply of the NH ₃ gas are stopped. After the film forming process is completed in this manner, the semiconductor wafer W
Is carried out, a semiconductor wafer W to be processed next is carried in, and a similar film forming process is performed thereon.

After such a film formation process is performed on a predetermined number of semiconductor wafers W, the stage 3 and the shower head 10 are cooled down to a predetermined temperature, and a ClF ₃ gas as a cleaning gas is supplied into the chamber 2 to perform cleaning. I do.

In the above-described series of steps, in the present embodiment, the following effects can be obtained by providing the shower head temperature control means 60 in the shower head 10.

At the time of precoating or film formation, TiCl _x (x
= 1, 2, 3), but it is necessary to volatilize such TiCl _x as a gas in order to form a stable film on the showerhead. For this purpose, a temperature of 425 ° C. or higher is required. However, the conventional heating of the shower head is passive heating by a heater in the stage.
There is no guarantee that the temperature of the shower head will be 425 ° C. or higher, and a stable precoat film cannot be formed on the shower head. On the other hand, by providing the shower head temperature control means 60 in the shower head 10 as in the present embodiment, the shower head 10 can be positively set at 425 ° C. or higher, preferably 500 ° C. or higher. A stable precoat film can be reliably formed.

When the inside of the chamber 2 is heated to the film forming temperature, when the temperature of the shower head 10 is raised only by the radiant heat of the stage 3 as in the conventional case, it takes a long time to stabilize at the predetermined heating temperature. In short, in the present embodiment, in addition to the passive heating from the heater 6 of the stage 3, the heater 1
Since the shower head 10 can be positively heated in advance by 7 and 18, the entire shower head 10 is heated in a short time, and the surface temperature of the lower plate 10c of the shower head 10 is stabilized at a substantially constant temperature. Be transformed into
For this reason, the temperature in the chamber 2 can be stabilized at a predetermined temperature in a short time. As described above, the temperature of the shower head 10 is uniformly controlled, so that the semiconductor wafer W
It becomes possible to form a Ti film uniformly on the upper surface. In particular,
The effect is remarkable when the size of the apparatus is increased due to the increase in the size of the semiconductor wafer to 300 mm.

Furthermore, since the high-frequency power supply is turned off during idling, the temperature of the heater in the stage is conventionally set higher to maintain the temperature of the shower head 10 at a predetermined temperature. . On the contrary,
By controlling the temperature of the shower head 10 by the shower head temperature control means 60 as described above, the temperature during idling can be maintained at a predetermined temperature and stabilized.

Further, at the time of cleaning, the temperature of the shower head 10 is set at 200 to 300 ° C. from the film forming temperature.
The cleaning temperature has to be lowered to the cleaning temperature of the prior art. Conventionally, it took a long time to lower the temperature due to poor heat radiation of the shower head, but in the present embodiment, it is a component of the shower head temperature control means 60. By supplying dry air as a cooling medium from the dry air supply pipes 61a and 61b to the upper portion of the shower head 10 and cooling it,
The inside of the chamber 2 can be quickly lowered to the cleaning temperature.

In the apparatus of this embodiment, since the upper surface of the upper plate 10a of the shower head 10 exists in the atmosphere, most of the members of the shower head temperature control means 60 can be provided in the atmosphere. The handling of the shower head temperature control means 60 is easy.

As described above, the inside heater 17 and the outside heater 18 are provided as a heating mechanism of the shower head temperature control means 60 to perform two-zone control. As shown in FIG. 9, the detection of the thermocouple 65a or 65b is performed. The temperature controller 67 controls the inner heater 17 so that the temperature becomes the set temperature.
And the temperature is controlled so that the difference between the detected temperature of the thermocouple 66a or 66b at the position corresponding to the outer heater 18 and the detected temperature of the thermocouple 65a or 65b corresponding to the inner heater 17 becomes zero. By controlling the output of the outer heater 18 by the heater 68, the outer portion of the shower head 10 is controlled so as to always have the same temperature as the inner portion, so that heat dissipation from the outer portion of the shower head 10 is suppressed. Temperature controllability can be improved. In particular, when the size of the semiconductor wafer is 30
When the size is increased to 0 mm, heat is easily dissipated from the outside of the shower head 10, and thus such control is more effective.

At the time of maintenance of the shower head 10, the shower head 10 is turned out of the chamber 2 by the turning mechanism 80. Thereby, the shower head 10
As shown in FIG. 11, since maintenance can be performed with the gas discharge surface facing upward, maintenance can be performed extremely easily. Specifically, from the state of FIG. 11, first, the plurality of support members 49 can be removed outward, then the filler 48 can be removed upward, and then the lower plate 10c and the middle plate 10b of the shower head 10 can be removed upward. Since these detaching operations are extremely easy, maintenance can be performed very easily.

The present invention is not limited to the above embodiment, but can be variously modified within the scope of the concept of the present invention. Hereinafter, such a modified example will be specifically described.

As shown in FIGS. 5 and 6, in the above embodiment, the gas supplied via the second gas passage 12b is supplied to the second gas passage 1 at a substantially central portion of the space 11b.
The liquid is directly diffused into the space 11b from the discharge port 121 of the nozzle 2b. However, in such an embodiment, the gas supplied through the second gas passage 12b may not be sufficiently diffused into the space 11b. Therefore,
Second gas passage 12b at a substantially central portion of space 11b
It is preferable to connect a gas diffusion promoting pipe to the discharge port 121 of the above. FIG. 12 shows such an example. In the example of FIG. 12, substantially H is placed in the space 11b above the lower plate 10c.
A letter-shaped gas diffusion promoting pipe 110 is provided.
This gas diffusion promoting pipe 110 is connected to the discharge ports 12 on both sides.
1 and a central pipe 110a directly fitted to
It has two side tubes 110b, 110c which are vertically joined (welded) to both ends of Oa and integrated therewith. Gas discharge ports 110d are provided at both ends of the side pipes 110b and 110c.
Are formed so as to open toward the upper plate 10a side. Then, the gas discharged from the discharge port 121 passes through the central pipe 110a and the side pipes 110b and 110c, and a total of four gas discharge ports 110d provided at both ends of the side pipes 110b and 110c, respectively. Direction. Therefore, the gas supplied through the second gas passage 12b can be sufficiently and uniformly diffused into the space 11b. Side tubes 110b, 11
Both ends of Oc are supported by two support members 110e and 110f, thereby preventing the center tube 110a from being shaken. Note that the number and the mode of the openings of the gas discharge ports 110d are not particularly limited as long as the gas supplied through the second gas passage 12b can diffuse sufficiently and uniformly into the space 11b. However, it is preferable that the gas discharge ports 110d are evenly arranged in the space 11b. FIG.
FIG. 3 is a cross-sectional view showing a state where the middle plate 10b is attached to the lower plate 10c and the gas diffusion promoting pipe 110 shown in FIG. As can be understood from this figure, the support member 110e is connected to the side tubes 110b, 11b from above.
0c, and the support member 110f supports the side tubes 110b and 110c while being sandwiched between the middle plate 110b and the lower plate 110c.

FIG. 14 and FIG. 15 show modifications of the control system. FIG. 14 is a schematic diagram showing a modification of a portion corresponding to the heating mechanism of FIG. 9, and FIG.
FIG. 11 is a diagram showing a modification of the control mode of FIG. 10. In the example of FIG. 14, the control system and each thermocouple 65a, 65b, 66a, 66b
15, and in the example of FIG. 15, the control system and each heater 17,
18 is provided with a noise filter 120.
By providing the noise filter 120 in this manner,
Noise from the high frequency power supply 47 can be effectively removed, and control characteristics can be improved.

Further, in the modified example shown in FIG. 16, the outer heater 1 which is a ring-shaped sheath heater having a circular cross section is used.
Instead of 8, an outer heater 118 having a donut-shaped flat heater similar to the inner heater 17 is provided. Thus, the shape of the heater is not particularly limited.
Further, instead of the insulating member 72, a thicker insulating plate 131 is interposed between the inner heater 17 and the upper plate 10a, and a thick insulating plate 132 is also interposed between the outer heater 118 and the upper plate 10a. I have. Since the upper plate 10a functions as an electrode for plasma generation, it is necessary to suppress the influence of noise received by the heater. Therefore, it is preferable to provide such thick insulating plates 131 and 132. From the viewpoint of effectively preventing the influence of noise, the thickness of such an insulating plate is preferably 0.5 to 10 mm. Such insulating plates 131 and 13
No. 2 needs to have high thermal conductivity and heat resistance. Therefore, as a material of the insulating plates 131 and 132, ceramics having high thermal conductivity and heat resistance such as aluminum nitride are preferable.

Further, in the modification shown in FIG. 17, instead of the elastic member 50 interposed between the side surface of the concave portion 48a of the filler 48 and the side surface of the convex portion 49a of the support member 49 in FIG. An elastic member 150 made of a corrosion-resistant metal spring formed of a Ni alloy material such as Inconel is interposed. Thus, the mode of the elastic member interposed between the side surface of the concave portion 48a of the filler 48 and the side surface of the convex portion 49a of the support member 49 is not particularly limited.

In the above embodiment, the film forming process of the Ti film has been described as an example. However, the present invention is not limited to this and can be applied to the CVD film forming process of another film such as a TiN film. Also,
Although the case where plasma is formed has been described as an example, plasma is not always essential. The temperature control means of the shower head is not limited to the above configuration, either.
The control method is not limited to the above method. For example using dry air as a refrigerant Ar, may be another gas N ₂ and the like. When plasma is not used, a liquid such as water can be used as the refrigerant. Furthermore, although the processing of a semiconductor wafer has been described as an example, the present invention is not limited to this, and can be applied to processing of other substrates such as a glass substrate for a liquid crystal display device.

[0067]

As described above, according to the present invention,
Since the shower head is provided with the temperature control means, the shower head can be positively controlled to a desired temperature instead of being heated by radiation. Can be done in time. In addition, since the temperature of the shower head can be positively controlled, the temperature stability in the chamber can be increased.

Further, by providing the shower head with the temperature control means as described above, the shower head can be controlled to a desired temperature during film formation or pre-coating, so that a stable film can be formed on the shower head. As a result, a uniform film can be reliably formed on the object.

Further, since the temperature control means of the shower head is provided in the atmosphere side, the temperature control means can be handled in the atmosphere of the atmosphere, and the handling is easy.

Further, since the shower head is provided with a reversing mechanism for turning the shower head to the outside of the chamber and reversing the shower head, the shower head can be almost completely out of the chamber. This can be performed very easily.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a CVD film forming apparatus according to an embodiment of the present invention.

FIG. 2 is a plan view showing an upper part of a shower head of the CVD film forming apparatus according to one embodiment of the present invention.

FIG. 3 is an enlarged view showing a shower head of the apparatus of FIG.

FIG. 4 is a sectional view taken along line AA in FIG. 3;

FIG. 5 is a sectional view taken along line BB of FIG. 3;

FIG. 6 is a bottom view and a side view showing a gas discharge section from a second gas passage.

FIGS. 7A and 7B are a bottom view and a side view showing another example of a gas discharge section from a second gas passage.

FIG. 8 is an enlarged sectional view showing a filler portion of the apparatus of FIG. 1;

FIG. 9 is a schematic diagram showing a part corresponding to a heating mechanism in the temperature control means of the apparatus shown in FIG. 1;

FIG. 10 is a diagram showing a preferred control mode when heating is controlled by the temperature control means of the apparatus of FIG. 1;

11 is a sectional view showing a state where the shower head of the apparatus of FIG. 1 is inverted by an inversion mechanism.

FIG. 12 is a plan view showing a lower plate when a gas diffusion promoting pipe is provided.

FIG. 13 is a cross-sectional view of a state in which a middle plate is attached to the lower plate and the gas diffusion promoting pipe in FIG. 12;

FIG. 14 is a schematic view showing a modification of a portion corresponding to the heating mechanism of FIG. 9 in the temperature control means of the apparatus of FIG. 1;

FIG. 15 is a diagram showing a preferable control mode when heating is controlled by the temperature control means of FIG. 14;

FIG. 16 is a sectional view showing a modification of a portion corresponding to a heating mechanism.

FIG. 17 is a sectional view showing a modified example of the filler portion of FIG. 8;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1; CVD film-forming apparatus 2; Chamber 3; Stage 6; Heater 10; Shower head 10a; Upper stage plate 10b; Middle stage plate 10c; Lower stage plate 10d; Horizontal part 10e; Supporting part 10f; Cover member 17; inner heater (heating mechanism) 18; outer heater (heating mechanism) 20; heat insulating member 25a, 25b; gas pipe 30; gas supply unit 47; high-frequency power supply 48; filler 49; Member 53; Exhaust device 60; Shower head temperature control means 61a, 61b; Dry air supply pipe (cooling mechanism) 62; Controller 63, 64; Power supply 65a, 65b, 66a, 66b; Thermocouple (Temperature detecting mechanism) 67, 68 Temperature controller 80; reversing mechanism W; semiconductor wafer (substrate to be processed)

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4K030 CA04 CA12 EA04 JA10 KA22 KA23 KA25 KA39 KA41 4M104 BB14 BB30 DD44 DD45

Claims (17)

[Claims] 1. A chamber for performing a film forming process on a substrate to be processed, a mounting table for mounting the substrate to be processed in the chamber, and a shower head having a plurality of gas discharge holes provided to face the mounting table. And a gas supply mechanism for supplying a processing gas into the chamber via the shower head, and a shower head temperature control means for controlling the temperature of the shower head. 2. The film forming apparatus according to claim 1, wherein the chamber is configured to be able to be evacuated. 3. A chamber for performing a film forming process on a substrate to be processed in a vacuum atmosphere, a mounting table for mounting the substrate to be processed in the chamber, and a plurality of gas discharge holes provided to face the mounting table. A shower head having: a gas supply mechanism for supplying a processing gas into the chamber via the shower head; and a shower head temperature control means for controlling a temperature of the shower head. It has a portion inside the chamber located inside the chamber including the hole forming surface, and an atmosphere side portion located outside the chamber on the atmosphere side, and the shower head temperature control means is provided on the atmosphere side portion of the chamber. A film forming apparatus characterized by the above-mentioned. 4. The apparatus according to claim 1, further comprising a mounting table heating means for heating the mounting table.
The film forming apparatus according to any one of the above. 5. The film forming apparatus according to claim 1, further comprising a chamber heating means for heating the chamber. 6. The showerhead temperature control means includes a heating mechanism for heating the showerhead, a cooling mechanism for cooling the showerhead, a temperature detection mechanism for detecting a temperature of the showerhead, and a detection result of the temperature detection mechanism. The controller according to claim 1, further comprising: a controller for controlling at least the heating mechanism based on the controller.
The film forming apparatus described in the above section. 7. The heating mechanism has an inner heater that heats an inner part of the shower head, and an outer heater that heats an outer part, and the temperature detecting mechanism detects the temperature of the inner part. The film forming apparatus according to claim 6, further comprising a temperature detection unit and an outside temperature detection unit that detects a temperature of the outside portion. 8. The controller controls the inner heater so as to reach a set temperature based on a detection value of the inner temperature detector, and reduces a detected temperature difference between the inner temperature detector and the outer temperature detector to zero. 7. The film forming apparatus according to claim 6, wherein the outer heater is controlled so as to be as follows. 9. The film forming apparatus according to claim 1, wherein a heat insulating material is provided facing a surface of the shower head opposite to the chamber. 10. The showerhead according to claim 1, wherein the showerhead has a showerhead main body and an annular support portion continuous above the outer periphery of the showerhead main body, and the support portion has a rib structure. Any one of items 1 to 9
A film forming apparatus according to the item. 11. The film forming apparatus according to claim 10, wherein a heat insulating material is provided above the shower head main body and inside the support portion. 12. An annular filling member between the shower head and the chamber wall, and a member for fixing the filling member, and an elastic member is provided between the filling member and the member for fixing the filling member. The film forming apparatus according to claim 1, wherein the film forming apparatus is interposed. 13. The plasma processing apparatus according to claim 1, further comprising plasma generation means for generating a plasma of a processing gas in the chamber.
The film forming apparatus described in the above section. 14. The film forming apparatus according to claim 1, further comprising a reversing mechanism for rotating the shower head to the outside of the chamber and reversing the shower head. 15. A shower head having a chamber for forming a film on a substrate to be processed, a mounting table for mounting the substrate in the chamber, and a plurality of gas discharge holes provided to face the mounting table. And a gas supply mechanism for supplying a processing gas into the chamber via the shower head, and a reversing mechanism for turning the shower head to the outside of the chamber and reversing the same. 16. An annular filling member between the shower head and the chamber wall surface, and a member for fixing the filling member, and an elastic member is provided between the filling member and the member for fixing the filling member. The film forming apparatus according to claim 15, wherein the film forming apparatus is interposed. 17. The fixing member can be detached outward with the shower head turned upside down, and the filling member can be detached upward after detaching the fixing member outward. 17. The film forming apparatus according to claim 16, wherein maintenance of the shower head can be performed after removing the filling member upward.