JPH0936209A - Film formation device and substrate supporting jig for use in this device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a film formation device capable of accurately suppressing production of particles when performing film formation process, and a substrate supporting jig for use in this device. SOLUTION: A specific reaction gas is introduced into a vertical furnace, and film formation process is performed by phase reaction with respect to a substrate W supported by a substrate supporting jig. A plurality of pillars 11 are provided vertically so as to correspond to a circumferential portion of the substrate W, and also a placing part 12 for placing the substrate W on each pillar 11 is provided, and a fine projection 15 is appropriately formed on a placing face 14 of each of the placing parts 12. The placing part 12 is composed of a recess groove 13 formed in a direction normal to the pillar 11. The substrate W is supported under condition of point contact by the fine projection 15 in the placing part 12 of the pillar 11. Connection quantity of a deposit film 16 in a contact portion can remarkably be reduced to suppress a generation of particles.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film forming apparatus for forming a thin film or the like on a silicon wafer (substrate) used for manufacturing a semiconductor device, and more particularly to a substrate supporting jig used in this film forming apparatus. It is a thing.

[0002]

2. Description of the Related Art In a film forming apparatus of this type, particularly in a vertical vapor phase reaction apparatus for simultaneously forming a film on a plurality of substrates, a substrate supporting jig (so-called a so-called jig for supporting a substrate on which a film forming process is performed) , Boats) are used. FIG. 3 and FIG.
1 shows a configuration of a main part of a conventional batch type vertical gas phase reactor. This film forming apparatus introduces a predetermined reaction gas into a vertical furnace (not shown) and performs a film forming process on a silicon wafer W supported by a boat 1 which is a substrate supporting jig by a gas phase reaction. ing.

The boat 1 is provided with a plurality of pillars which are erected parallel to each other in a vertical furnace so as to correspond to the peripheral portion of the silicon wafer W. For example, the illustrated example has four columns 2 to 5, and each column is arranged so as to equally divide the periphery of the silicon wafer W as shown in FIG. Each of the columns 2 to 5 has a mounting portion 2 for mounting the silicon wafer W formed at a predetermined pitch along the axial direction (vertical direction).
It has a, 3a, 4a or 5a. And one silicon wafer W is supported with the mounting portions 2a to 5a at the same height position between the columns 2 to 5 as one set. In the boat 1, the set of the mounting portions 2a to 5a is configured in multiple stages to support a large number of silicon wafers W as shown in FIG.

The pillars 2 to 5 preferably have a columnar shape, and when the mounting portions 2a to 5a are formed, for example, a concave groove is formed by cutting an inner portion of the pillar 2 in a direction orthogonal to its axis. To do. A groove is similarly formed in the columns 3 to 5. The mounting surfaces 2a to 5a are formed by the lower surfaces of the grooves of the columns 2 to 5, respectively, and the mounting portions 2a to 5a support the peripheral portion of the silicon wafer W as shown in FIGS. 3 and 4. . Then, a film formation process is performed on the silicon wafer W thus supported by the boat 1.

[0005]

However, in the conventional vertical gas phase reactor, the film formation process is performed while the silicon wafer W is supported by the boat 1, so that not only the silicon wafer W but also the boat 1 is processed. However, the film is deposited. In this case, as shown in FIG. 5, the silicon wafer W is in close contact with, for example, the mounting portion 2a of the column 2 of the boat 1 in the form of surface contact. Therefore, the deposited film 6 grows so as to be connected at the contact portion between the silicon wafer W and the mounting portion 2a. When the deposited silicon wafer W is removed from the boat 1, the deposited film 6 thus connected is peeled off along the boundary with the mounting portion 2a. Then, particles of the deposited film 6 are generated from the peeled portion, and if the particles adhere to the silicon wafer W, there is a problem that the quality is deteriorated.

In view of the above situation, it is an object of the present invention to provide a film forming apparatus capable of reliably suppressing the generation of particles during the film forming process, and a substrate supporting jig used in this apparatus.

[0007]

A substrate supporting jig according to the present invention is a substrate supporting jig for supporting a substrate which is to be housed in a furnace and subjected to a film forming process. In addition to providing a plurality of upright columns corresponding to the above, each of the columns is provided with a mounting portion for mounting the substrate, and a microprojection is formed at an appropriate place on the mounting surface of each mounting portion. is there.

Further, in the substrate supporting jig of the present invention, the mounting portion is composed of a concave groove formed by engraving in a direction orthogonal to the axis of the column, and the mounting surface is formed in a part of the concave groove. This is set.

Further, in the substrate supporting jig of the present invention, the mounting portion is composed of a projecting piece which is provided so as to project in a direction orthogonal to the axis of the support column, and the mounting surface is provided on a part of the projecting piece. This is set.

Further, in the film forming apparatus according to the present invention, any one of the above substrate supporting jigs is installed in a vertical furnace, and a predetermined reaction gas is introduced into the vertical furnace to support the substrate supporting jig. A film forming process is performed on the formed substrate by a gas phase reaction.

[0011]

According to the present invention, a plurality of columns vertically provided so as to correspond to the peripheral portion of the substrate (silicon wafer) are provided with mounting portions for mounting the substrate, and the mounting portions are mounted on the mounting portions. Place the substrate. In particular, the mounting portion is formed by a recessed groove formed in a direction orthogonal to the axis of the support column, and the mounting surface is set in a part of this recessed groove. Then, minute protrusions are formed at appropriate places on the mounting surface. The substrate is supported by the small protrusions on the mounting portion of the support, that is, in a point contact state.

Therefore, in a film forming apparatus equipped with such a substrate supporting jig, when the substrate and the mounting portion are brought into contact with each other in a minimum area and a predetermined reaction gas is introduced into the vertical furnace to perform the film forming process, It is possible to significantly reduce the amount of connection between the deposited films at the contact portion between the two. Therefore, when removing the substrate after film formation from the substrate support jig, even if the deposited film that is connected in this way is peeled off, particles do not substantially occur, or a very small amount that does not cause quality problems. Only particles are generated.

Further, according to the present invention, the mounting portion is constituted by a projecting piece projecting in a direction orthogonal to the axis of the column, and the mounting surface may be set on a part of this projecting piece. Good. That is, in the case of providing the mounting portion, a groove is formed in the column, or such a projecting piece is formed, and in any case, by projecting the minute protrusions from the mounting surface of the mounting portion, the substrate and Generation of particles can be effectively suppressed by minimizing the contact area of the mounting portion.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, based on FIGS. 1 and 2, the same reference numerals are used for the members which are substantially the same as or correspond to those of the conventional example, and a film forming apparatus according to the present invention and a substrate support used in this apparatus are shown. A preferred embodiment of the jig will be described.

In the present embodiment, the present invention is applied to a vertical vapor phase reaction apparatus for simultaneously performing film formation processing on a plurality of silicon wafers W as described above, and a substrate supporting treatment described later is provided in the vertical furnace. Equipped with ingredients. Then, a predetermined reaction gas is introduced into the vertical furnace, and the film formation process is performed on the silicon wafer W by a gas phase reaction.

FIG. 1 and FIG. 2 show the essential structure of the present invention. In this film forming apparatus, a boat 10 which is a substrate supporting jig is installed in a vertical furnace (not shown), and the boat 10 supports the silicon wafer W. The boat 10 is preferably provided with four columns 11 that are erected parallel to each other in a vertical furnace so as to correspond to the peripheral portion of the silicon wafer W.

Although only one pillar 11 is shown in the figure, four pillars 11 are arranged so as to equally divide the periphery of the silicon wafer W. Each of the columns 11 has a mounting portion 12 for mounting the silicon wafer W formed at a predetermined pitch along the axial direction (vertical direction). Then, one silicon wafer W is supported by setting the four mounting portions 12 at the same height position between the columns 11 as one set. By forming a set of mounting portions 12 constituted by the columns 11 in multiple stages, a large number of silicon wafers W are stacked and supported.

The pillar 11 is preferably cylindrical in this embodiment as well. The concave groove 13 is formed by cutting the inner part of the pillar 11 in a direction orthogonal to the axis thereof. A mounting surface 14 of the mounting portion 12 is set by a part of the recessed groove 13, that is, a surface below the recessed groove 13. This mounting surface 14
Are arranged in a substantially horizontal direction in the vertical furnace and are located in the peripheral portion of the silicon wafer W. By providing the mounting surface 14, the silicon wafer W is mounted so that the outer peripheral edge (arc portion) of the silicon wafer W passes through substantially the diameter of the column 11, as shown in FIG.

Microprotrusions 15 are formed at appropriate places on the mounting surface 14 (which may be substantially in the center as shown in FIG. 2). As shown in FIG. 1, the minute protrusions 15 are preferably formed so as to protrude from the mounting surface 14 in an arc shape, for example. In the set of the mounting portions 12 of each of the columns 11, such a minute protrusion 15 is provided on the mounting surface 14. The silicon wafer W is supported by the four minute protrusions 15 for each set of the mounting portions 12 of the support column 11, that is, in a four-point contact state.

By the way, the fine projections 15 have a
In reality, the top is slightly crushed or flattened.
That is, strictly speaking, the silicon wafer W placed on the silicon wafer W is not in point contact but in slight surface contact. This contact portion is roughly circular and its diameter d
Is about 0.2 mm. Then, the outer peripheral length of the contact portion between the silicon wafer W and the minute projections 15 at this time is
It becomes about 0.6 mm. On the other hand, here, as described in the conventional example, when the silicon wafer W is mounted on the mounting portion 12 by surface contact (see FIG. 5), the contact between the silicon wafer W and the mounting portion of the substrate supporting jig is performed. The outer peripheral length of the portion is about 25 mm.

Now, in the film forming apparatus of the present invention equipped with the substrate supporting jig having the above structure, the silicon wafer W is supported by the boat 10 in the vertical furnace and a predetermined reaction gas is introduced into the vertical furnace. Then, a film forming process is performed. By this film forming process, the deposited film 16 is formed on both the silicon wafer W and the substrate supporting jig as shown in FIG. Since the silicon wafer W is supported in the point contact state by the minute protrusions 15 on the mounting portion 12 of the pillar 11, the connection amount of the deposited film 16 at the contact portion between the two can be significantly reduced. Therefore, even if the deposited film 16 is peeled off to remove the film-formed silicon wafer W from the substrate supporting jig, substantially no particles are generated.

In the above embodiment, an example in which the mounting portion 12 is constituted by the concave groove 13 formed in the inner portion of the column 11 has been described. Further, according to the present invention, the mounting portion can also be configured by a projecting piece (not shown) projecting in a direction orthogonal to the axis of the column 11. Then, a mounting surface is set on a part of the projecting piece, and minute protrusions similar to those in the above-described embodiment are formed at appropriate places on the mounting surface. Also in this case, the silicon wafer W can be formed by projecting the minute protrusions from the mounting surface of the mounting portion.
Also, it is possible to minimize the contact area of the mounting portion and effectively suppress the generation of particles.

[0023]

As described above, according to the present invention, in the film forming apparatus of this type, the film is formed by supporting the substrate in the point contact state by the minute projections in the mounting portion for mounting the substrate. The amount of connection of the deposited film at the contact portion with the substrate formed by the treatment can be significantly reduced. This has the advantage that the generation of particles can be effectively suppressed when the deposited film is peeled off, and the quality of the silicon wafer can be improved.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of essential parts according to an embodiment of a substrate supporting jig in a film forming apparatus of the present invention.

FIG. 2 is a plan view of an essential part of an embodiment of a substrate supporting jig in the film forming apparatus of the present invention.

FIG. 3 is a schematic vertical sectional view of a substrate supporting jig in a conventional film forming apparatus.

FIG. 4 is a plan view of a main part of a conventional film forming apparatus.

FIG. 5 is a cross-sectional view of a main part of a substrate supporting jig in a conventional film forming apparatus.

[Explanation of symbols]

 10 Boat 11 Support 12 Placement 13 Recessed Groove 14 Placement Surface 15 Small Protrusion

Claims (4)

[Claims] 1. A substrate supporting jig for supporting a substrate to be subjected to a film forming process, which is housed in a furnace, and comprises a plurality of upright columns which are provided upright so as to correspond to a peripheral portion of the substrate. A substrate supporting jig, which is provided with a mounting portion for mounting the substrate on each of the columns, and minute protrusions are formed at appropriate places on the mounting surface of each mounting portion. 2. The substrate supporting jig according to claim 1, wherein the placing portion is a groove formed by engraving in a direction orthogonal to the axis of the column, and is mounted on a part of the groove. A substrate support jig, characterized in that the placement surface is set. 3. The substrate supporting jig according to claim 1, wherein the placing portion is formed by a projecting piece that projects in a direction orthogonal to the axis of the supporting column, and is mounted on a part of the projecting piece. A substrate support jig, characterized in that the placement surface is set. 4. The substrate supporting jig according to any one of claims 1 to 3 is installed in a vertical furnace, and a predetermined reaction gas is introduced into the vertical furnace to be supported by the substrate supporting jig. The film forming apparatus is characterized in that a film forming process is performed on the substrate by a gas phase reaction.