JP4019466B2 - Film forming device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a film forming apparatus used for manufacturing various electronic devices, using a semiconductor device as a representative example, and more particularly to a technique for reliably carrying out attachment / detachment and conveyance of an object to be manufactured in the film forming apparatus.
[0002]
[Prior art]
In the manufacturing process of various electronic devices, film formation using techniques such as sputtering, CVD, and PVD is performed. At the time of film formation, an article to be manufactured (hereinafter collectively referred to as a base) is mounted on a support having a heating unit or the like, and a predetermined portion of the upper surface of the base is pressed onto a base with a fixing jig. Generally done. This fixing jig often also serves to prevent the film from adhering to a surface other than a predetermined surface of the substrate. In film formation using plasma or the like, a clamp that covers the entire periphery of the substrate. A ring or the like (hereinafter collectively referred to as a fixing jig) is frequently used.
[0003]
FIG. 6 shows a cross-sectional view of a conventional example of the technique related to the fixing jig 7. FIG. 6A) shows a low pressure CVD apparatus (Japanese Patent Laid-Open No. 3-215670). The inside of the container 1 provided with the cooling pipe 2 is a reaction chamber 3. A heater 5 is incorporated in the heating unit 4 on which the substrate 6 is mounted. Further, the base 6 is pressed and fixed by a fixing jig 7. The fixing jig 7 is provided with an Al film 8 that reflects the radiant heat from the heating unit 4, and the end of the fixing jig 7 is in contact with the cooled container 1, and the temperature rise of the fixing jig 7 is reduced. Has been. It is also disclosed that an Al fixing jig is used instead of using the Al film 8. A film is formed by decomposition of the reaction gas in the reaction chamber 3 and thermal reaction. Film formation on the surface of the fixing jig at a lower temperature is suppressed, and the thickness distribution of the film formed on the exposed surface at the center of the base 6 is improved.
[0004]
FIG. 6B) shows a film forming apparatus for sputtering, which is a conventional example related to fixing of the substrate 6 (Japanese Patent Laid-Open No. 6-188303). When the heating unit 4 also serving as the cathode is moved upward by the lifting device 9, the mounted base 6 is fixed by the claw portion 10 of the fixing jig 7. In order to prevent the claw portion 10 from being excessively pressed against the base 6 due to the movement error of the lifting device 9, the pressing is finely adjusted by the adjusting screw 11 and the moving mechanism 12. A voltage is applied between the target 13 and the heating unit 4 and plasma discharge is performed to form a film on the exposed surface at the center of the substrate 6.
[0005]
The fixing jig 7 and the claw portion 10 of FIGS. 6A) and B) prevent the film from being formed around the side surface and the back surface of the base 6. FIG. 6C) shows an enlarged view of another conventional example of the fixing jig 7. The base 6 mounted on the heating unit 4 is fixed by a pressing portion 7 a of a fixing jig 7. The eaves portion 7b is for suppressing film formation on the base 6 portion in the vicinity of the pressing portion 7a. The fixing jig 7 forms a film within the effective film formation range, which is the exposed surface of the substrate 6, while preventing the film from wrapping around the back surface of the substrate 6.
[0006]
On the other hand, it is important from the standpoint of increasing the yield of production to make the effective area where the film of the substrate 6 is formed, that is, the exposed surface of the substrate 6 as large as possible. For this reason, it is necessary to arrange the fixing jig 7 so as to cover only the region of the base 6 that is as close to the periphery as possible. In addition, the base body 6 tends to increase in size.
[0007]
Corresponding to these situations, it is important to rationally form a film in order to increase the functionality of various electronic devices and reduce costs.
[0008]
[Problems to be solved by the invention]
After the film is formed on the substrate having a high temperature, a sticking phenomenon between the substrate and the fixing jig may occur. As the size of the base increases, the probability that this sticking will increase further increases as the total length of the fixing jig contacting and pressing the peripheral surface of the base becomes longer. For example, in the high temperature film formation process of Al in the manufacturing process of a semiconductor device, the substrate and the fixing jig are not smoothly separated, which hinders the automation of film formation, and further, the substrate and the fixing jig. The tool is firmly fixed and the substrate is damaged.
[0009]
The cause of this sticking phenomenon is considered to be a result of a synergistic effect of the phenomenon that a film forming material such as Al wraps around between the substrate and the fixing jig and the temperature of the contact surface. In order to avoid the sticking phenomenon, it is necessary to reduce the wraparound of the film forming material as much as possible or to suppress the temperature rise of the contact surface.
[0010]
As countermeasures against the wraparound of the film forming material, there are conventional countermeasures as shown in FIGS. 6B) and C). This will be described with reference to FIG. The eaves portion 7b suppresses the film-forming material from wrapping around the contact surface between the base 6 and the fixing jig 7, that is, the pressing portion 7a. If the depth of the eaves portion 7b is increased, the effect of suppressing the wraparound can be increased, but there is a problem that the effective range for forming a film on the substrate 6 is reduced.
[0011]
In order to suppress the temperature rise of the contact surface, it is necessary to take a measure in consideration of the heat from the heating unit on which the substrate is mounted and the film formation using the plasma in consideration of the radiant heat of the plasma. In the conventional example of FIG. 6A, the influence of radiant heat from the heating unit 4 is suppressed, but no consideration is given to conduction heat. In addition, the cooling of the fixing jig 7 by contact with the container 1 requires the positioning of the fixing jig 7 on the upper surfaces of both the base 6 and the container 1, and there is a problem that it takes time and effort for reliable operation.
[0012]
In view of these problems, the present invention easily suppresses the wraparound of the film forming material and the temperature rise of the contact surface between the base and the fixing jig without reducing the effective area where the film is formed, and accompanies the aforementioned sticking phenomenon. A film forming apparatus for avoiding trouble is provided.
[0013]
[Means for Solving the Problems]
One solution of the present invention is a film forming apparatus provided with an improved fixing jig that suppresses the wraparound of the film forming material.
[0014]
A fixing jig disposed on a surface of a predetermined portion of the substrate, generally a peripheral portion of the substrate surface on which the film is formed, includes a first portion contacting the substrate and an inner side connected to the first portion. There is a second portion facing the substrate at a predetermined interval on the (exposed surface side of the substrate), and the surface of the second portion facing the substrate is made concave to solve the problem.
[0015]
It can also be solved by roughening the surface of the second portion facing the substrate to increase the effective area. The effect is further enhanced if the surface of the second part facing the substrate is concave and roughened.
[0016]
The means for suppressing the wraparound of the film forming material according to the present invention effectively wraps around the area of the second portion facing the substrate without increasing the area covering the substrate of the fixing jig. The film-forming material is efficiently captured. That is, since the tip of the second part and the base are at a predetermined interval, the amount of wraparound to the second part does not change, but most of it is captured by the base-facing surface of the second part, and the base of the first part The probability of going to the contact surface with is reduced. As a result, even if the film is formed on the high temperature substrate, the occurrence of the sticking phenomenon between the substrate and the fixing jig can be suppressed.
[0017]
Another solving means of the present invention is a film forming apparatus provided with means for suppressing the temperature rise of the contact surface between the base and the fixing jig.
One is to suppress the temperature rise of the fixing jig due to radiant heat such as plasma used for film formation. A hollow portion that provides heat conduction resistance is provided inside the fixing jig to suppress heat conduction of radiant heat received by the surface of the fixing jig to the contact surface with the base. In particular, providing the hollow portion in the region of the fixing jig in contact with the base body is effective in suppressing the temperature rise of the contact surface.
[0018]
The second relates to the improvement of the heating section. Fixture, the product, in the heating portion of the heating unit and is stacked in the order area, one is only set a recess in the heating section by reducing the contact area between the product and the other fixed jig of the product A cooling mechanism is provided in the area on the back side of the surface that comes into contact with the tool to suppress the temperature rise of the contact surface.
[0019]
The concave portion of the former heating unit suppresses the temperature rise of the substrate on the region, the temperature of the contact surface between the substrate and the fixing jig corresponding to the position also decreases, and the sticking between the substrate and the fixing jig is prevented. It is suppressed.
[0020]
The latter corresponds to the contact area between the workpiece and the fixing jig, and is provided with a cooling mechanism in the heating portion, and suppresses the temperature rise of the contact surface between the workpiece and the fixing jig by local heat dissipation. . In this cooling, it is desirable to provide means for controlling the temperature of the cooling mechanism in order to reduce the thermal stress of the heating section and to secure the temperature distribution of the effective film formation range of the product .
[0021]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a cross-sectional view showing an outline of a film forming apparatus, taking film formation by sputtering as an example. Although means such as evacuation, vacuum sealing, and gas introduction are not shown, generally known film forming means may be used.
[0022]
A film forming chamber 21 surrounded by the container 20 and the upper lid 28 of the film forming apparatus is provided. The film forming chamber 21 includes a heating unit 23 fixed to a lift 22 that moves up and down, a transport mechanism 24 for a base 25, a shield unit 27, and a fixing jig 26 fixed to the heating unit 23. A sputtering target 29 is fixed to the upper lid 28, and a magnet assembly 30 for controlling plasma is disposed.
[0023]
The base 25 is transported to the center by the transport mechanism 24 in a state where the heating unit 23 is located below. The heating unit 23 is raised by the lift 22, and the base 25 is transferred from the transport mechanism 24 onto the heating unit 23. Further, the heating unit 23 is raised, and the periphery of the base 25 is pressed against the fixing jig 26. The fixing jig 26 presses the base body 25 with an appropriate force by the shield portion 27 and the like acting on the elastic force. The state of pressing will be described in detail later.
[0024]
The substrate 25 is heated by the heating unit 23. A gas is introduced into the film forming chamber 21 to generate plasma in the space between the target 29 and the heating unit 23. The film forming material sputtered from the target 29 is deposited on the exposed surface of the substrate 25 and formed into a film. When the film formation is completed, when the plasma is stopped and the heating unit 23 is lowered, the formed substrate 25 is moved to the transport mechanism 24 and transported to a predetermined position (not shown). A new substrate 25 is placed on the transport mechanism 24, and a film is formed through the same process as described above.
[0025]
In the present invention, after the film is formed, means described in detail later is used so that when the heating unit 23 is lowered, there is no sticking phenomenon between the base 25 and the fixing jig 26 and the base 25 is also smoothly lowered. ing.
[0026]
FIG. 2 is a cross-sectional view of an example of the fixing jig 26 that suppresses the wraparound of the film forming material, which is one of the causes of sticking between the base body 25 mounted on the heating unit 23 and the fixing jig 26. Indicated. The main point of the present embodiment is to increase the capture rate of the film forming material on the inner surface of the eaves part 26b of the fixing jig 26 in order to reduce the wraparound of the film forming material into the gap between the pressing part 26a and the base 25. Out. The present invention is not limited to the illustrated example as long as it conforms to the main point. The material of the fixing jig 26 should be selected in consideration of fastness, temperature resistance, degassing property, etc., based on the film formation conditions, and stainless steel is a typical example.
[0027]
2A) and 2B), the surface of the eaves portion 26b facing the base 25 is made concave, the area is enlarged, and the film forming material that wraps around from the front end of the eaves portion 26b can be captured on the surface. If the distance between the tip of the eaves portion 26b and the base 25 is constant, the amount of wraparound is equal, but the capture rate at the inner surface of the eaves portion is increased, and the amount of wraparound film forming material reaching the tip of the pressing portion 26a is reduced. Can be reduced.
[0028]
In FIG. 2C, the inner surface portion 26c of the eaves portion 26b facing the base body 25 is roughened to increase the effective area, and the trapping rate of the wrapping film forming material on the inner surface is increased. The amount of the film forming material that reaches the tip of the pressing portion 26a can be reduced. If the inner surface of the eaves part 26b having the shape of FIGS. 2A) and B) is roughened, the capture rate can be further increased.
[0029]
As described above, since the capture rate of the film forming material on the inner surface of the eaves portion 26b is increased, the width of the eaves portion 26b can be narrowed within an allowable range. The effective range of film formation of the base 25 is expanded, and the yield of manufacturing electronic devices such as semiconductor devices is increased.
[0030]
FIG. 3 is a cross-sectional view showing an example in which a hollow portion 26d is provided in the region of the pressing portion 26a in order to suppress the temperature rise of the contact surface between the pressing portion 26a of the fixing jig 26 and the base body 25. Due to the radiant heat of the plasma described with reference to FIG. In the heat conduction to the contact surface of the heat, the hollow portion 26d acts as a resistance component of conduction.
[0031]
In FIG. 3A), the radiant heat absorbed by the lid 26e of the fixing jig 26 is suppressed from reaching the contact surface with the base body 25 by the action of the hollow portion 26d. This is an example including a configuration in which the inner surface of the eaves portion 26b is concave to increase the capture rate of the film-forming material that wraps around as described above.
[0032]
FIG. 3B) shows an example in which the hollow portion 26d has a slit shape. The purpose is to increase the resistance of heat conduction to the contact surface and to promote heat dissipation from the vicinity of the surface of the fixing jig 26.
[0033]
The temperature rise due to the radiant heat from the plasma or the like is suppressed, and the sticking between the pressing portion 26a of the fixing jig 26 and the base body 25 is reduced.
4 and 5 are partial cross-sectional views showing an example in which the heat of the heating portion 23 is suppressed from being transmitted to the contact surface between the pressing portion 26a of the fixing jig 26 and the base body 25. FIG.
[0034]
The configuration of FIG. 4 will be described. A heating unit 23 is fixed to a hollow lift 22. A heater plate 32 is provided on the upper surface of the heating unit 23 and is heated by the heater wire 31. The base plate 25 is mounted on the heater plate 32 and is pressed by the pressing portion 26 a of the fixing jig 26.
[0035]
A cooling mechanism 33 is provided in the region of the heating unit 23 where the contact surfaces of the pressing unit 26a and the base body 25 overlap. The cooling mechanism 33 is supplied with a liquid or gaseous heat transfer medium from a pipe 34 in the hollow of the lift 22 and discharged from a pipe (not shown).
[0036]
The heat of the contact surface between the base body 25 and the pressing portion 26a is conducted downward through the base body 25 and the heater plate 32 and is released from the cooling mechanism 33. This cooling may be performed at a temperature that does not cause a sticking phenomenon between the pressing portion 26 a and the base body 25. Excessive cooling may cause thermal stress in the heating unit 23 and poor temperature distribution of the substrate 25. Therefore, the temperature of the medium is set in consideration of the film formation conditions, the flow rate of the heat transfer medium flowing through the cooling mechanism 33, and the like. It is desirable to adjust. Although the temperature adjustment of the cooling medium is not shown, the temperature of the tank of the heat transfer medium or the like may be controlled by a commonly used temperature adjusting means.
[0037]
FIG. 5A) shows an example in which a heating chamber 37 provided with a heating element 35 and a cooling mechanism 36 are connected. The arrangement relationship of the cooling mechanism 36 with respect to the contact surface between the base 25 and the pressing portion 26a and the arrangement of the fixing jig 26, the base 25, the heater plate 32, and the like are substantially the same as in the case of FIG.
[0038]
A heat transfer medium is introduced into the cooling mechanism 36 from the passage 38 in the heating unit 23. The heat transfer medium that has absorbed the heat of the heater plate 32 and the base body 25 directly above the cooling mechanism 36 is sent to the heating chamber 37 through the connection path 40. A part of the heat transfer medium is used to transfer the heat of the heating element 35 to the heater plate 32. The heat transfer medium is discharged from the passage 39 in the heating unit 23. You may circulate through a tank etc. It is also possible to provide a valve (not shown) in the connection path 40, adjust the flow rate of the heat transfer medium, and control the temperature difference between the cooling mechanism 36 and the heating chamber 37.
[0039]
FIG. 5B) shows an example in which the concave portion 41 is provided in the heating portion 23 so as to correspond to the contact surface between the base body 25 and the pressing portion 26a. In the recess 41, the temperature increase of the contact surface is suppressed by the amount of heat transfer from the heating unit 23 to the base 25. Although the groove-like recess 41 is shown in the figure, it is also possible to control the heat transfer condition by changing the dot area and the surface density of the dot-like recess.
[0040]
In the above description, the heat transfer from the heating unit 23 to the base body 25 shows the heat conduction by the mutual contact, but is not limited to this. For example, a fine hole may be provided in the heater plate 32, an inert gas may be used for the above-described heat transfer medium, a part of the hole may be discharged from the hole, and heat transfer between the heating unit 23 and the base 25 may be performed. .
[0041]
【The invention's effect】
The first and second aspects reduce the amount of the film forming material from entering the contact surface between the base and the fixing jig, and suppress the sticking phenomenon. In addition, the effective film formation range of the substrate is expanded.
[0042]
The third to sixth aspects reduce the temperature rise of the contact surface between the base and the fixing jig and suppress the sticking phenomenon.
As a result of these, the yield, yield, apparatus availability, etc. in the manufacture of electronic devices such as semiconductor devices are increased.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an outline of a film forming apparatus using a sputtering apparatus as an example.
FIG. 2 is a cross-sectional view showing an embodiment of an eaves portion of a fixing jig.
FIG. 3 is a cross-sectional view showing an embodiment in which a hollow is provided in the fixing jig.
FIG. 4 is a cross-sectional view showing an example of a heating unit.
FIG. 5 is a cross-sectional view showing another embodiment of the heating unit.
FIG. 6 is a cross-sectional view showing a conventional example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Container 2 Cooling pipe 3 Reaction chamber 4 Heating part 5 Heater 6 Base | substrate 7 Fixing jig 7a Pressing part 7b Eaves part 8 Al film 9 Lifting device 10 Claw part 11 Adjustment screw 12 Moving mechanism 13 Target 20 Container 21 Film formation chamber 22 Lift 23 heating unit 24 transport mechanism 25 base 26 fixing jig 26a pressing part 26b eaves part 26c inner surface part 26d hollow part 26e lid 27 shield part 28 upper lid 29 target 30 magnet assembly 31 heater wire 32 heater plate 33 cooling mechanism 34 piping 35 heating element 36 Cooling mechanism 37 Heating chamber 38 Passage 39 Passage 40 Connection path 41 Recess

Claims (2)

One surface of the product is heated in contact with the heating unit, and a predetermined part of the other surface of the product is supported by being covered with a fixing jig, and the product other than the predetermined part is exposed. In a film forming apparatus in which a film is formed on the surface,
A cooling mechanism for releasing heat of the contact surface between the product to be manufactured and the fixing jig is provided only in a region of the heating portion where the product is overlapped with a predetermined portion covered with the fixing jig. A film forming apparatus. 2. The film forming apparatus according to claim 1, further comprising means for controlling the temperature of the cooling mechanism.

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