JP2533551Y2 - Semiconductor wafer holding jig - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a semiconductor wafer holding jig for aligning and holding a large number of semiconductor wafers under a heating atmosphere, and in particular, unloading a wafer into a vertical heating furnace. The present invention relates to a semiconductor wafer holding jig suitable for use as a so-called wafer boat.

2. Description of the Related Art Conventionally, in a semiconductor manufacturing process, a wafer boat in which the wafers can be arranged and arranged has been used in order to improve mass productivity and facilitate transportation, and a large number of wafers are loaded and unloaded into a heat treatment furnace. Heat treatment.

Such a boat generally uses a quartz glass material in terms of heat resistance, chemical stability, and the like, and a plurality of quartz rods extending along a furnace tube extending along a vertical direction facing each other. On the inner wall side of the thick plate-shaped member or the arc-shaped member curved along the inner wall of the furnace tube, a large number of wafer holding grooves are engraved at predetermined intervals, respectively. In many cases, a large number of semiconductor wafers are arranged in a line at a single point or at a plurality of points while the wafer periphery is locked.

In the cross-sectional shape of such a holding groove, there are various shapes such as a rectangular groove, a V-shaped groove, and a Y-shaped groove in a wafer boat mounted in a core tube having a horizontal structure. In order to achieve this, a so-called vertical heat treatment apparatus in which a furnace core tube is disposed in a vertical direction has been proposed. In a vertical boat used in such an apparatus, as shown in FIG. In order to prevent the dropped wafer 1 from dropping, the holding groove 30 of the wafer 1 is formed to be slightly inclined from the horizontal direction. In such a vertical boat, a rectangular groove is used or the opening end side of the rectangular groove is used. In fact, only the chamfered groove shape is used and the holding groove shape is not sufficiently studied as in the horizontal boat.

SUMMARY OF THE INVENTION In view of the drawbacks of the prior art, the present invention has an object to provide a semiconductor wafer holding jig having a vertical structure capable of securely holding a wafer 1 in surface contact while ensuring sufficient wraparound of a processing gas. .

[Means for Solving the Problems] In order to achieve such technical problems, the present invention requires that the width of the bottom surface 3B of the holding groove for holding the peripheral edge of the semiconductor wafer 1 be substantially equal to or slightly larger than the thickness of the wafer 1. That is,
That is the bottom width d ₁ and more specifically, is formed to face toward the opening side of the both ends of the wafer 1 thickness w from [+ 0.01 to 0.5 mm] The extent slightly set point to large bottom 3B Point having upper wall 4B and lower wall 5B (FIG. 2).

The upper wall 4B forms an obtuse angle with respect to the bottom surface 3B and the bottom surface 3B
Is a sloped wall extending toward the opening end 41 with a wedge-shaped space in cross section from the peripheral edge of the wafer in contact with.

The lower wall 5B has a turning portion 51 that is bent at an intermediate position from the bottom end 32 toward the opening end 52 side, and at least a surface 53 from the bottom end 32 position of the turning wall 5B to the turning portion 51 is formed. This is a surface that holds the wafer 1 in a substantially surface contact state and that the opening end 41 is inclined in a divergent manner from the diverted portion 51, in other words, the facing distance with the wafer 1 is changed in a direction in which it is gradually separated. A semiconductor wafer holding jig having a second surface 54 functioning as a wall as a constituent requirement is proposed.

In this case, when the holding groove is formed on the inner wall side of a thick plate-shaped member or an arc-shaped member curved along the furnace tube inner wall, the cross-sectional shape becomes almost the same cross-sectional shape at any position. However, especially when the holding groove is formed on the peripheral surface of the quartz rod, the cross-sectional shape varies along the circumferential direction.
Therefore, the holding groove having the above-described configuration may have the above-described configuration at least in a groove shape at a portion in contact with the wafer peripheral edge, more specifically, at a position having the deepest groove depth.

According to the experimental results of the present invention, the holding groove depth d ₂
Is [d ₂ -d ₃ ≧ d / 100], and the bottom width d ₁ of the holding groove is the opening angle θ ₂ is [θ ₁ + 10 ° to 50 °].
d ₃ is d ₃ ≧ 1 / 5d ₁ , and the wedge-shaped space angle θ ₁ is [10 ° to 60 °]
It was understood that it was good to set to.

d: Wafer diameter “action” According to the holding groove 2B, since the opening end 41 side where the wafer 1 first enters is V-cut on both sides by the upper wall 4B and the second surface 54, the wafer 1 enters. It is easy to make one side V-cut (wedge-shaped space) at an intermediate position, but since the upper wall 4B forming the wedge-shaped space is formed up to the bottom end 31 like a V-shaped holding groove, the Y-shaped groove is formed. Bottom width like holding groove of
d ₁ is not necessary to set the Hododai occurrence of rattling, for example in order from the wafer thickness w is readily fitted and held only set to slightly larger, vibration and during the heat treatment at the time of wafer instrumentation and out Even if cracks occur, there is no backlash, so that the occurrence of scratches, particles, etc. due to collision or abrasion of the wafer processing surface can be prevented.

Further, since the main holding groove 2B is capable of mounting or holding the wafer 1 in a surface contact state by the surface 53 of the lower wall 5B, and the groove width clearance on the bottom side is small, the present holding means 2B has When the holding groove 2B is applied to a vertical boat, the wafer 1
Regardless of the case where the device is installed horizontally or when installed at an angle, the holding groove 2B
Even if it is shallow to a certain extent, the risk of falling off due to vibration etc. can be reduced.

Further, in the present technical means, as shown in FIG. 2, the processing gas can be formed to the peripheral edge position of the wafer surface by using the upper wall 4B formed without surface contact with the wafer. Will be performed more smoothly,
It becomes easy to form a uniform film on the wafer 1.

As shown in FIG. 2, the thin wafer 1 is
It is extremely preferable that there is no danger of welding or deformation during the heat treatment because it is held in a surface contact state, and wedge-shaped spaces are formed on both the upper and lower sides, so that the gas flows smoothly.

The wafer 1 is stable for setting the claim 2 wherein the retaining groove 2A depth d ₂ as according to the invention shown in FIG. 1 (d) according to _{[d 2 -d 3 ≧ d /} 100] And d ₁ is the opening angle θ
_{When 2 is set} to [θ ₁ + 10 ° to 50 °], d ₃ ≧ 1 /
To set to 5d _1, can smoothly inserted without the wafer 1 is abuts the open end 41. In addition, the wedge-shaped space angle θ _{1 is set} to [10 °
~ 60 °], it is possible to ensure a smooth gas flow.

Hereinafter, preferred embodiments of the present invention will be illustratively described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention to only those components, unless otherwise specified. It's just

FIGS. 1 (A) and 1 (B) show the overall shape of a horizontal boat 10 according to a reference example of the present invention, in which a pair of tubular connecting rods 11 arranged at both ends in the longitudinal direction have a central lower surface and an upper surface both ends. To each
A pair of support rods 12 and 13 extending in parallel are disposed and welded, and the wafer holding grooves 2A are formed in a multi-stage along the axial direction on the upper surface side or the inner peripheral side facing the respective support rods 12 and 13. The peripheral edge of the disc-shaped wafer 1 is locked in the holding groove 2A, and a large number of wafers 1 can be aligned and arranged by a plurality of points.

Figure 1 (c) shows a cross-sectional shape of the holding groove 2A which is engraved on such a support rod 12, the bottom width d ₁ of the parallel with the support rod axis holding groove 2A wafer 1 thickness w Of the pair of side walls 4A and 5A formed to face the opening side from both ends of the bottom surface 3A, and set the processing to about [w + 0.01 to 0.5 mm]. The side wall 4A in the direction in which gas enters is formed as an inclined side wall 4A extending in a divergent manner from the bottom end 31 toward the opening end 41 side. The inclination angle θ of the side wall 4A
₁ is preferably set in the range of 10 ° to 60 °.

On the other hand, the side wall 5A on the side facing the inclined side wall 4A is the bottom end.
After extending vertically (hereinafter referred to as a first surface 53) to a position halfway toward the opening end 41 from the end 31, the bent portion 51 is bent.
A deflection wall 5A having a second surface 54 inclined outward from the position and having a substantially Y-shaped cross section on one side is formed.

The holding groove 2A is brought into contact with the first surface 53 and the bottom surface 3A by causing the wafer 1 to enter the holding groove 2A while being guided by the inclined side wall 4A and the second surface 54. As a result, the wafer 1 is placed vertically.

The processing of the holding groove 2A is performed in a state in which the support rods 12, 13 and the connecting rod 11 are welded to predetermined positions, respectively, and the diameter is the same as the diameter of the wafer 1 and the peripheral cross-sectional shape matches the shape of the holding groove 2A. It can be easily processed by rotating the plate-shaped diamond cutter from the upper position while entering.

In the holding groove 2A as well, the operation of the present invention described above can be smoothly achieved.
Figure holding groove depth d ₂ as shown in _{(d) [d 2 -d 3} ≧ d / 100]
Wafer 1 is held stably by setting the obtained also d ₁
When the opening angle θ _{2 is set} to [θ ₁ + 10 ° to 50 °], by setting d ₃ ≧ 1 / 5d ₁ , the wafer 1
It can be inserted smoothly without abutting on Also in order to ensure the wraparound smooth gas a wedge-shaped space angle θ ₁ [10 ° ~6
0 °].

FIG. 2 is a vertical boat in which the holding grooves shown in FIG.
In the embodiment of the present invention used in 20, the upper wall 4B is located on the upper surface side and the lower wall 5B is located on the lower surface side as described above, and the holding groove formed to be slightly inclined upward with respect to the vertical axis.
2B of the bottom width d ₁ of the large slightly above the wafer thickness w, specifically while set to the wafer thickness w + 0.01 to 0.5 mm] extent, facing towards from bottom surface 3B opposite ends on the opening side formed The upper wall 4B to be formed is an inclined side wall extending in a divergent shape from the bottom end 31 toward the opening end 41. The inclination angle θ ₁ of the side wall 4B is 1
It is better to set it in the range of 0 ° to 60 °.

On the other hand, the lower wall 5B is vertically extended (hereinafter, referred to as a first surface 53) from the bottom end 31 to an intermediate position toward the opening end 41, and then bent, and is inclined outward from the position of the turning portion 51. A deflected wall 5B having a substantially Y-shaped cross section and a second surface 54
And

The holding groove 2B is brought into contact with the first surface 53 and the bottom surface 3B by moving the wafer 1 into the holding groove 2B while being guided by the upper wall 4B and the second surface 54. As a result, the wafer 1 is placed almost horizontally slightly upward.

The processing of the holding groove 2B is also performed by the support rods 14, 15A, 15B and the ring 1
In a state where the base 6 and the lower base 17 are respectively welded to predetermined positions shown in FIG. It can be easily processed by entering while rotating from the direction.

In the case of the vertical boat 20, since it is preferable that the wafer 1 is disposed with a slight inclination, the holding grooves 2B formed on the support rods 14, 15 are also preferably inclined at a predetermined angle.

For example, as shown in FIG. 3, a vertical boat 20 is provided with three support rods 14, 15A, 15B vertically erected between a ring 16 arranged at the upper end and a lower base 17, and The holding grooves 2B, 2B 'are engraved in multiple stages along the axial direction on the inner peripheral surface side of the rods 14, 15A, 15B, and the wafer is inserted into the surrounding space of the support rods 14, 15A, 15B. When one peripheral edge is locked in the holding grooves 2B, 2B 'and a large number of wafers 1 can be arranged vertically by three-point support, the holding grooves located on the side facing the wafer 1 entry direction 2B may be formed by slightly inclining the entire holding groove 2B slightly upward with the bottom end 32 between the bottom surface 3B and the first surface 53 as a fulcrum, and the holding groove 2B 'located on the side may have a cutting direction. Support rod
It may be formed to be slightly inclined with respect to 15 axes.

Upper wall 4B which is located on the upper surface side as described above, according to this embodiment, with the wafer 1 periphery is easy guiding of the wafer 1 is to be formed to the bottom surface 3B abuts the bottom width d ₁ Since it can be formed to a thickness substantially equal to the wafer thickness w, no backlash occurs, and it is held in a state of surface contact with the first surface 53 on the lower wall side, so that there is no risk of welding or deformation during heat treatment. Very preferred.

[Effects] As described above, according to the present invention, a wedge-shaped space through which gas can easily enter can be formed on the upper surface of the wafer, and the groove opening has V-cut shapes on both the upper and lower sides. There is no danger of abutting against the end 41, and the wafer 1 can be held in contact with two or more surfaces, the lower surface and the end surface. In this case, the versatility is high, the yield is improved without generation of dust on the wafer 1 due to damage or wear, the adhesion of impurities during heat treatment and uneven wear are prevented, and the durability of the boat itself is greatly improved. Can be done.

And so on.

[Brief description of the drawings]

FIG. 1 shows a horizontal boat according to a reference example of the present invention,
(A) is an overall perspective view, (B) is a cross-sectional view, and (c) is a cross-sectional view of a main part showing a cross-sectional shape of a holding groove engraved on the boat. (D) is an explanatory view. FIG. 2 is a sectional view of a main part showing a sectional shape of a holding groove according to an embodiment of the present invention used in a vertical boat, and FIG. 3 is a perspective view showing a vertical boat in which the holding groove is engraved. is there. 1: semiconductor wafer, w: thickness 2B: holding groove, 3B: bottom surface 4B, 5B: side wall, 31, 32: bottom end 41: open end, 51: turning part 53: top surface, 54: bottom surface

Claims (2)

(57) [Scope of request for utility model registration] A holding groove for holding a peripheral edge of a semiconductor wafer is vertically stacked, and a bottom surface contacting the peripheral edge of the wafer is formed with a width substantially equal to or slightly larger than the thickness of the wafer. A semiconductor wafer holding jig having a vertical structure having an upper wall and a lower wall formed toward the opening side from both ends, wherein the upper wall forms an obtuse angle with respect to the bottom surface and has a wedge-shaped cross section from a peripheral edge of a wafer in contact with the bottom surface. An inclined wall extending toward the opening end, wherein the lower wall is a turning wall which is turned substantially downward at a position substantially perpendicular to the bottom surface toward the opening end, and the turning wall is A second surface in which the distance between the first surface holding the wafer and the opening end from the deflected portion to the deflected portion from the bottom end position to the deflected portion is changed in a direction in which the facing distance with the wafer is gradually separated. Is a combination of Semiconductor wafer holding jig according to claim. Wherein said retaining groove depth _{d 2 [d 2 -d 3 ≧} d / 100, d: wafer diameter, also {wafer meat a bottom width d ₁ of the holding groove thickness w +
0.01 to 0.5 mm], the opening angle _{θ 2 [θ 1 + 10 °} ~50 °],
According to claim 1, wherein the second up diverting part of the surface of the depth _{d 3 d 3 ≧ 1 / 5d} 1, that further each set of wedge-shaped spaces angle theta ₁ to the [10 ° ~60 °] A semiconductor wafer holding jig.