JP2907401B2 - Sputter deposition equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sputter film forming apparatus.

[0002]

2. Description of the Related Art Conventionally, the materials of a deposition-preventing plate and a shutter for shutting off sputtered atoms during pre-sputtering, which are arranged in a film forming chamber of a sputter film forming apparatus, are generally made of SU.
It is made of S material, has good compatibility with metal oxides and metal nitrides, and has been used with sandblasting to form a matte surface to increase the film adhesion strength. However, since the SUS material is not sufficient for the problem of particles during sputtering and the like, an aluminum material (Al) having a large film adhesion strength has recently been used.

[0003]

However, the Al material used in the above-mentioned conventional technique has a very good film adhesion strength of a sputtered film (it is difficult to peel up to 500 μm), but has a large thermal expansion coefficient. 23.1 × 10 ⁻⁶ ) Because of its low mechanical strength (Young's modulus: 0.757 × 10 ¹¹ N / m ² ), it was used in the vicinity of the cathode (target) and in the shutter where the temperature rose sharply in the film formation chamber. In this case, there is a problem that the film is deformed by the influence of heat or the stress of the film formed by the attached sputtered atoms, causing film peeling which causes dust. This is because, as shown in FIG. 4, immediately after cleaning of the film forming chamber, the above-mentioned anti-adhesion plate and shutter are also cleaned, so that the yield is good, but the temperature in the film forming chamber rises as the number of sputtering increases. At the same time, the amount of film attached to the deposition-preventing plate and the shutter also increases, which is a major cause of a decrease in yield.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and has as its object to provide a sputter film forming apparatus which suppresses generation of film forming defects and has a high yield.

[0005]

According to the present invention, there is provided a sputter film forming apparatus provided with a film forming chamber for forming a metal oxide film and a metal nitride film. is attached to the inside of the deposition chamber, a shutter plate for sputtering atoms interrupted to be used in the deposition preventing plate and pre-sputtering for preventing dust generation, low thermal expansion coefficient, and a member high mechanical strength becomes, the surface of the member is sprayed coating material having a large film adhesion strength relative to the sputtered film
Characterized by that, with the deposition preventing plate and the shutter plate is at 3.5 to 7.5 × 10 ^-6 in coefficient of thermal expansion, and Young's modulus of 1.7 to 3.3 × 10 ¹¹ N Do / m ² in the range of member
Rannahli, or are sprayed coated surface of the member is aluminum, also, the surface of the deposition preventing plate and the shutter plate is Ru textured der.

[0006]

According to the sputter film forming apparatus of the present invention, the thermal expansion coefficient of the deposition-preventing plate and the shutter in the film forming chamber is reduced, the mechanical strength is increased, and the adhesion strength of the sputtered film is increased. This is to prevent the sputtered film from adhering to the deposition-preventing plate and the shutter during film deposition or pre-sputtering, or to prevent the sputtered film from peeling off due to deformation of the deposition-preventing plate and the shutter due to heat.

[0007]

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view showing one embodiment of a film forming chamber of the sputter film forming apparatus of the present invention.

In the film forming chamber 4 of this embodiment, a deposition-preventing plate (not shown) for preventing dust generation is mounted on the entire inner surface, and a target 5 for emitting sputtered atoms is fixed to the side wall. The backing plate 6 and the substrate holder 3 for holding the substrate 2 are attached to face each other. Further, between the backing plate 6 and the substrate holder 3, during pre-sputtering for cleaning the surface of the target 5 fixed to the backing plate 6, the arrival of sputtered atoms to the substrate holder 3 is blocked. Is rotatably supported by a shutter support 7. Further, a sputter flow blocking wall 8 having a circular opening is provided between the shutter 1 and the substrate holder 3.

The shutter 1 is moved between the target 5 and the substrate 2 held by the substrate holder 3 to a position for closing the opening of the sputter flow blocking wall 8 during pre-sputtering to block the sputtered atoms. However, at the time of film formation by sputtering, the film is removed from the position at the time of the pre-sputtering and is moved to a position where the sputtered atoms are not cut off.

As shown in FIG. 2A, the shutter 1 has a circular shape having a size substantially equal to the opening of the sputter flow blocking wall 8, and is shown in FIG. As shown, the surface of a shutter plate 1a made of a material having a low coefficient of thermal expansion and a high mechanical strength is spray-coated with a coating material 9 having a high film adhesion strength. In such a shutter 1, the thermal expansion coefficient or the mechanical strength of the shutter plate 1a and the coating material 9 may be different, but the coating material 9 is spray-coated on the surface of the shutter plate 1a to form an extremely thin film. Since the deformation rate is small even when the film is deformed due to an increase in temperature in the film forming chamber 4, the film is not peeled off from the shutter plate 1a.

The deposition-preventing plate and the sputter flow blocking wall 8 attached to the film forming chamber 4 are made of the same material as the shutter plate 1a, and the surface thereof is coated with the coating material 9. It is.

When performing sputtering film formation in the film forming chamber 4 described above, an argon (Ar) gas is injected into the film forming chamber 4 to maintain a predetermined pressure, and the target 5 and the substrate 2 are formed.
And a sputtering voltage is applied. By applying the sputtering voltage, an electric field is generated in the film forming chamber 4, and the Ar ions are accelerated by the electric field and collide with the target 5. Thereby, a sputtered atom is generated from the target 5 and reaches the substrate 2 disposed to face the target 5 to form a film on the substrate 2. Also, in the case of pre-sputtering, sputter atoms are generated in the same manner, and foreign substances and the like attached to the surface of the target 5 are removed together with the sputter atoms. The sputtered atoms and the removed foreign matter do not go to the substrate 2 side but adhere to the surface of the shutter 1 or the inner surface of the film forming chamber 4.

Next, a specific example of the sputter deposition performed by using the deposition chamber 4 will be described. (Specific Example 1) SiO ₂ (oxide film) using the film forming chamber 4
Is formed by sputtering.

In the shutter 1, a molybdenum material (coefficient of thermal expansion: 3.7 × 10 ^-6 , Young's modulus: 3.27 × 10 ¹¹ N / m ² , film adhesion strength: 付 着 100) is used as the shutter plate 1a.
aluminum (Al) (film adhesion strength: ５０50) as a coating material 9 on the surface thereof using
(It is difficult to peel off to 0 μm) is spray-coated with a thickness of 0.3 mm, and further, the whole surface is sand-blasted by sandblasting. Here, the sputtering film forming conditions will be described.

(1) Ar gas pressure in the film forming chamber: 0.3 Pa (2) Sputtering power: 5 kW (3) Substrate cleaning: heating is performed at 200 ° C. in a cleaning chamber (not shown), and thereafter, the film forming chamber is heated. Conveyed to

The target 5 is pre-sputtered.
After cleaning, a film was formed by sputtering.

The results are shown in FIG. 3 in comparison with a conventional case where a thermal spray coating is not performed and a shutter and a deposition-preventing plate formed only of molybdenum are used.

As is clear from FIG. 3, it was confirmed that a difference in the occurrence rate of film defects appeared with an increase in the number of times of sputtering (the number of injected Lots).

As described above, this film defect is caused by deformation of the shutter 1 or the protection plate due to the influence of heat, the stress of the film formed by the attached sputtered atoms, and the like. When the film attached to the deposition plate is peeled off, it becomes a foreign substance and floats in the film forming chamber, and is generated when the foreign substance adheres to the surface of the substrate 2 together with sputtered atoms.

Aluminum (Al) used as the coating material 9 for the shutter 1 and the anti-adhesion plate used in this example
Has a higher film adhesion strength than the molybdenum material, so that the amount of foreign matters floating in the film forming chamber is smaller than the case where the thermal spray coating is not used, and the result as described above appears. is there. (Specific Example 2) A film of Si ₃ N ₄ (nitride film) was formed under the same conditions using the same apparatus and shutter 1 as in the aforementioned specific example 1.

As a result, as described above, it was confirmed that a difference in the occurrence rate of film defects appeared as the number of times of sputtering increased. (Specific Example 3) SiO ₂ (oxide film) is formed under the same conditions using the same apparatus as those of the above specific examples 1 and ₂ .

The shutter 1 has a shutter plate 1a as tantalum (Ta) (thermal expansion coefficient: 6.3 × 10 ⁻⁶ , Young's modulus: 1.81 × 10 ¹¹ N / m ² , film adhesion strength: up to 250).
Aluminum (Al) is thermally spray-coated to a thickness of 0.3 mm on the surface of the surface, and similarly, the entire surface is sand-blasted to obtain a satin finish.

As a result, even if tantalum (Ta) is used as the shutter 1 as described above, the number of spatters is increased in the case of coating the surface and in the case of not coating, because aluminum has a higher film adhesion strength. It was confirmed that there was a difference in the occurrence rate of film defects according to the above.

[0025]

As described above, according to the present invention, the sputtered film adhered to the inner surface of the film forming chamber and the shutter is less likely to be peeled off during the sputter film formation or the pre-sputtering. Defects are suppressed, and a sputter film with good yield can be formed.

[Brief description of the drawings]

FIG. 1 is a sectional view showing one embodiment of a film forming chamber of a sputter film forming apparatus of the present invention.

FIGS. 2A and 2B are views showing a shutter used during pre-sputtering, wherein FIG. 2A is a perspective view thereof, and FIG.

FIG. 3 is a diagram showing an example of the relationship between the number of times of sputtering and the incidence of film defects in the sputter deposition apparatus of the present invention.

FIG. 4 is a diagram showing a relationship between the number of times of sputtering and the yield in a conventional sputtering film forming apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Shutter 1a Shutter plate 2 Substrate 3 Substrate holder 4 Film forming chamber 5 Target 6 Backing plate 7 Shutter support part 8 Sputter flow blocking wall 9 Coating material

Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI // H01L 21/203 H01L 21/203 S 21/285 21/285 S (72) Inventor Atsushi Koike 3-30-2 Shimomaruko, Ota-ku, Tokyo No. Canon Inc. (72) Inventor U. Yokoyama 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (56) References JP-A-61-56277 (JP, A) JP-A-2-2 285067 (JP, A) JP-A-63-238263 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C23C 14/00-14/58 H01L 21/203, 21/285

Claims (3)

(57) [Claims] 1. A sputter film forming apparatus provided with a film forming chamber for forming a metal oxide film and a metal nitride film, wherein the sputter film forming apparatus is provided inside the film forming chamber for preventing dust generation. a shutter plate for sputtering atoms interrupted to be used in the deposition preventing plate and pre-sputtering, low thermal expansion coefficient, and consists member mechanical strength is large, the surface of the member is the film adhesion strength relative to the sputtered film material having large A sputter film forming apparatus characterized in that the film is spray-coated with a. 2. A deposition preventing plate and the shutter plate, a thermal expansion coefficient at 3.5 to 7.5 × 10 ^-6, and a Young's modulus of 1.7
3.3 × consists 10 ¹¹ N / m ² in the range of members, sputter deposition apparatus of claim 1, wherein the this <br/> the surface of the member is sprayed coated with aluminum. 3. The sputter film forming apparatus according to claim 1 , wherein the surfaces of the deposition-preventing plate and the shutter plate are matted.