JP2016082082A - Quartz boat - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a quartz boat capable of elongating a maintenance cycle by suppressing film peeling.SOLUTION: The quartz boat includes: a plurality of support posts 4; and a support part 2, for supporting the support posts 4. The plurality of support posts 4 includes a substrate holding region 6, provided with a plurality of holing parts 5, for holding substrates. At least the support part 2 is made to be a rougher surface than the substrate holding region 6.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a quartz boat that holds a substrate typified by a silicon wafer and is disposed in a processing apparatus that processes the substrate.

  When film formation or heat treatment is performed on a substrate typified by a silicon wafer, the substrate is mounted on a quartz boat and placed in a processing apparatus.

  The quartz boat holds a plurality of substrates at a predetermined interval, and includes a support column that holds the plurality of substrates, and a support unit that supports the support column by fixing ends of the plurality of support columns. A plurality of substrates are held on the support at predetermined intervals (see Patent Document 1).

Japanese Patent Laid-Open No. 10-209063

  However, when forming a film on a substrate mounted on a quartz boat, the film is formed on the quartz boat at the same time as the substrate, and the quartz boat is generally mirror-finished, so that the film is formed on the quartz boat. There is a problem that the film is peeled off and becomes a foreign substance and soils the substrate. In particular, when a film is formed on the substrate by atomic layer deposition (ALD), the region outside the region holding the substrate of the quartz boat is at a lower temperature than the region holding the substrate, so the film is formed at a low temperature. The film becomes thick, and the film is easily peeled off from the quartz boat by the internal stress of the film.

  In addition, the quartz boat needs to perform maintenance for periodically removing the film. However, if the film attached to the quartz boat is easily peeled off, there is a problem that the maintenance cycle must be shortened.

  In view of such circumstances, an object of the present invention is to provide a quartz boat capable of suppressing film peeling and prolonging a maintenance cycle.

An aspect of the present invention that solves the above problem includes a plurality of support columns and a support unit that supports the plurality of support columns, and the plurality of support columns are provided with a plurality of holding units that hold a substrate. The quartz boat has a region, and at least the support portion is rougher than the substrate holding region.
In such an aspect, by roughening at least the support part that becomes low temperature when heated, the adhesion strength of the film formed on the support part is improved, and the peeling of the film formed on the support part is suppressed. be able to.

  Here, it is preferable that the support portion side of the support column is also rougher than the substrate holding region. According to this, it is possible to suppress peeling of the film formed in the low temperature region of the support by roughening the low temperature region of the support.

  Moreover, it is preferable that a heat insulating material is held on the support portion side of the support column and that the support portion side is rougher than the region including the region where the heat insulating material of the support column is provided. . According to this, peeling of the film formed in the heat insulation region can be suppressed by roughening the heat insulation region on the support portion side including the region provided with the heat insulating material that becomes low temperature.

It is a perspective view of the quartz boat concerning Embodiment 1 of the present invention. It is the top view and principal part sectional drawing of the quartz boat which concern on Embodiment 1 of this invention. It is a top view of the quartz boat which concerns on the comparative example of this invention.

Hereinafter, the present invention will be described in detail based on embodiments.
(Embodiment 1)
FIG. 1 is a perspective view of a quartz boat according to Embodiment 1 of the present invention, and FIG. 2 is a plan view of the quartz boat and a sectional view taken along line AA ′.

  As shown in the figure, the quartz boat 1 of the present embodiment is a vertical type arranged vertically, and includes two plate-like first and second support portions 2 and 3 and a first support portion 2. And a plurality of, in the present embodiment, four columns 4 provided between the second support portions 3.

The first support part 2 and the second support part 3 are plate-like ones made of quartz, that is, silicon dioxide (SiO ₂ ), and the quartz boat 1 is arranged vertically, that is, arranged in the vertical direction Z. In this case, the first support portion 2 is disposed on the lower side in the vertical direction Z and the second support portion 3 is disposed on the upper side in the vertical direction Z. In the present embodiment, the first support portion 2 corresponds to a support portion.

  The support column 4 is a columnar member made of quartz, and has one end fixed to the first support portion 2 and the other end fixed to the second support portion 3. A plurality of such columns 4, in the present embodiment, four in the longitudinal direction (axial direction) along the vertical direction Z so that the four are parallel between the first support portion 2 and the second support portion 3. Are arranged.

  In addition, each support column 4 is provided with a plurality of groove-shaped holding portions 5 opened on the side surfaces at predetermined intervals along the axial direction. By inserting the substrate 10 such as a silicon wafer into the holding unit 5 as described above, a plurality of the substrates 10 are held on the support column 4 at a predetermined interval along the axial direction. As described above, in this embodiment, an area in which the holding portion 5 of the quartz boat 1 is provided in the axial direction of the support column 4, that is, in the vertical direction Z in this embodiment, is referred to as a substrate holding area 6. In the present embodiment, the support 4 is provided with the groove-shaped holding portion 5 and the substrate 10 is held by inserting the substrate 10 into the holding portion 5. However, the present invention is not particularly limited to this. Alternatively, the support 4 may be provided with a projecting holding portion protruding from the side surface, and the substrate 10 may be placed on the holding portion. In any case, an area for holding the plurality of substrates 10 in the axial direction of the support column 4 is referred to as a substrate holding area 6.

  Further, in such a quartz boat 1, a heat insulating material 7 is provided on the first support portion 2 side with respect to the substrate holding region 6 of the support column 4. As the heat insulating material 7, a fiber heat insulating material such as glass wool or a foam heat insulating material such as foam can be used. By providing such a heat insulating material 7, when the quartz boat 1 holding the plurality of substrates 10 is heat-treated, the first support portion 2 side is set to a low temperature to support the first support portion 2. The influence of heat on can be suppressed. That is, when the quartz boat 1 holding the plurality of substrates 10 is heated, the first support portion 2 side of the support 4 is closer to the first support portion 2 in the axial direction (vertical direction Z) of the support 4. The temperature is lower than that of the holding region 6. In other words, the quartz boat 1 is heated (soaking length) so that the temperature distribution of the substrate holding region 6 is uniform in the axial direction of the support column 4 in the processing apparatus, but is outside the soaking length. In particular, a region insulated by the heat insulating material 7 (hereinafter referred to as a heat insulating region 8) is at a lower temperature than the substrate holding region 6.

  For this reason, in this embodiment, the surface of the heat insulating region 8 of the quartz boat 1 is roughened compared to the substrate holding region 6. Here, that the surface is roughened compared to the substrate holding region 6 means that a plurality of fine irregularities 9 are provided on the surface of the heat insulating region 8 compared to the substrate holding region 6. That is, it means that the surface roughness Ra of the heat insulating region 8 is larger than the surface roughness Ra of the substrate holding region 6. The method for roughening the heat insulating region 8 of the quartz boat 1 is not particularly limited, and examples thereof include dry etching such as ion milling, mechanical processing such as blasting represented by sandblasting, wet etching, and the like. Alternatively, the surface of the quartz boat 1 may be roughened by forming a film having an uneven surface. These roughening processes may be performed alone or in combination.

  In this way, by roughening the region of the quartz boat 1 where the temperature is low, in the present embodiment, the heat insulating region 8 is roughened, fine irregularities are formed in the region of the heat insulating region 8 where the temperature is low. The surface area per unit range can be increased compared to. Therefore, when a film is formed on the substrate 10 held by the quartz boat 1, the adhesion strength of the film formed in the heat insulating region 8 at a low temperature of the quartz boat 1 is improved by the anchor effect to form the heat insulating region 8. It is possible to suppress peeling of the formed film. In particular, when film formation is performed on the substrate held by the quartz boat 1 by atomic layer deposition (ALD), the low temperature region of the quartz boat 1 is formed as a thick film like chemical vapor deposition (CVD). Therefore, it is easy to peel off due to the internal stress of the film, but by roughening the heat-insulating region 8 having a low temperature, peeling can be suppressed even if the film is relatively thick.

  Here, for example, when the heat insulating region 8 of the quartz boat 1 is mirror-finished without being roughened, the film is formed on the substrate 10 held by the quartz boat 1 as shown in FIG. At the same time, a film 11 is formed in the heat insulating region 8 at the same time. And as shown in FIG.3 (b), when the film | membrane 11 formed into a film in the heat insulation area | region 8 peels, it will become a foreign material and will adhere to the board | substrate 10 grade | etc.,.

  In the present embodiment, the film 11 in the heat insulation region 8 is peeled off by suppressing the film 11 formed in the heat insulation region 8 from being peeled by roughening the heat insulation region 8 at a low temperature of the quartz boat 1. It is possible to suppress the generation of particles due to this, and it is not necessary to perform the maintenance for removing the film 11 in the heat insulating region 8 in a short period of time, and the maintenance cycle can be prolonged.

  The substrate holding region 6 of the quartz boat 1 is preferably mirror-finished. Thus, by mirror-treating the substrate holding region 6, it is possible to make the heat propagation to the substrate 10 held in the substrate holding region 6 uniform and to perform heat treatment on a plurality of substrates 10 under the same conditions. Become. Incidentally, when the substrate holding region 6 is roughened, the quartz boat 1 acts as a heat insulating material due to the roughening, and the film thickness uniformity in the surface of the substrate 10 is deteriorated. Further, by subjecting the substrate holding region 6 to a mirror finish, it is possible to suppress the consumption of raw materials during film formation on the substrate 10 and reduce the cost. Incidentally, if the substrate holding region 6 is roughened, the surface area of the quartz boat 1 increases, and the consumption of the raw material increases accordingly. Furthermore, by mirror-treating the substrate holding region 6, the slippage of the substrate 10 is improved, the inclination and floating of the substrate 10 are suppressed, and the error that the tweeter that transports the substrate 10 misses the substrate 10 is suppressed. Can do. Incidentally, if the substrate holding region 6 is roughened, the substrate 10 becomes slippery and the substrate 10 is tilted or lifted, resulting in an error that the tweezer misses the substrate 10.

(Other embodiments)
As mentioned above, although one Embodiment of this invention was described, the basic composition of this invention is not limited to what was mentioned above.

  For example, in the first embodiment described above, the heat insulating region 8 having a lower temperature than the substrate holding region 6 of the quartz boat 1 is roughened. However, the present invention is not particularly limited thereto. When the region closer to the second support portion 3 than the region 6 has a lower temperature than the substrate holding region 6, the region closer to the second support portion 3 than the substrate holding region 6 is roughened. Also good. That is, all the regions other than the substrate holding region 6 of the quartz boat 1 in the axial direction of the support column 4 may be roughened. That is, it is only necessary to roughen at least the region of the quartz boat 1 that is at a lower temperature than the substrate holding region 6. In Embodiment 1 described above, the heat insulating region 8 is roughened, but the lowest temperature is the first support portion 2 located farthest from the substrate holding region 6. Only one support portion 2 may be roughened. Of course, all the surfaces including the substrate holding region 6 of the quartz boat 1 may be roughened.

  Moreover, in Embodiment 1 mentioned above, although the heat insulating material 7 was provided, the heat insulating material 7 is not necessarily required and you may make it not provide the heat insulating material 7. FIG.

  Furthermore, in Embodiment 1 mentioned above, although the quartz boat 1 illustrated the vertical type | mold with which the axial direction of the support | pillar 4 is arrange | positioned in the perpendicular direction Z, it is not limited to this in particular, The axial direction (longitudinal of the support | pillar 4) The present invention can be applied to a so-called horizontal type in which the direction) is arranged in a horizontal direction orthogonal to the vertical direction Z.

  DESCRIPTION OF SYMBOLS 1 Quartz boat, 2 1st support part, 3 2nd support part, 4 support | pillar, 5 holding part, 6 board | substrate holding area, 7 heat insulating material, 8 heat insulating area, 10 board | substrate, 11 film | membrane

Claims (3)

Multiple struts,
A support portion for supporting a plurality of the columns,
The plurality of struts have a substrate holding region provided with a plurality of holding portions for holding a substrate,
At least the support portion is roughened more than the substrate holding region.   The quartz boat according to claim 1, wherein the support portion side of the support is roughened from the substrate holding region.   A heat insulating material is held on the support portion side of the support column, and the support portion side is rougher than the region including the region where the heat insulating material of the support column is provided. The quartz boat according to claim 1 or 2.

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