JPH11135606A - Wafer carrier for wafer cleaning - Google Patents

Abstract

(57) [Problem] To provide a wafer carrier for wafer cleaning in which dust generated from the carrier during cleaning is prevented from adhering to the wafer. SOLUTION: The wafer carrier 32 has a support portion 16 for supporting the wafer with the wafer surface vertical, and the support portion 16 is provided.
The wafer carrier is a wafer carrier for cleaning the wafer by immersing the wafer supported by the above in a cleaning fluid flowing upward to clean the wafer. The support portion 16 is formed as a pair of rods extending in the horizontal direction perpendicular to the wafer surface and in contact with and supporting the wafer peripheral edge 21, and is accommodated immediately below the horizontal center line of the wafer. It is arranged to be located on both sides of the wafer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wafer carrier for cleaning a wafer, and more particularly, to a wafer carrier for cleaning a wafer in which dust generated from the carrier during cleaning is prevented from adhering to the wafer.

[0002]

2. Description of the Related Art Conventionally, to clean a wafer with a cleaning liquid,
In general, a wafer is housed in a wafer carrier for wafer cleaning, the wafer carrier is immersed in a cleaning tank containing a cleaning liquid, a solvent is flown for cleaning, and then the wafer is exposed to isopropyl alcohol vapor to dry the wafer. . This is often done with automatic washing machines. As the cleaning liquid, for example, APM (ammonia hydrogen peroxide, a mixture of ammonia, hydrogen peroxide and water), HPM (hydrochloric acid peroxide), BHF (buffered acid), LE liquid (referred to as light etch liquid) , A mixed solution of hydrogen fluoride and water) and SPM (sulfuric acid peroxide). FIGS. 5A and 5B respectively show:
FIG. 2 is a perspective view of a conventional wafer carrier for wafer cleaning and a side view showing a conceptual configuration. A conventional wafer carrier 10 for cleaning a wafer (hereinafter, simply referred to as a wafer carrier 10) includes two support portions 16A and 16B having a groove 14 below the wafer carrier. In addition, the wafer carrier 10
Has three grooved holding portions 15A to 15F on the side walls 17A and 17B for holding the peripheral edge of the upper half portion of the accommodated wafer. The material of the wafer carrier 10 is, for example, quartz. As shown in FIG. 5, many conventional wafer carriers for cleaning wafers are accommodated with the orientation flat surface 12 facing downward.

FIG. 6 is an enlarged view of a cross section taken along the line II (see FIG. 5). Each of the support portions 16A and 16B includes a round bar-shaped member 18 provided horizontally and a square bar-shaped member 20 attached to the lower side of the member 18. The above-mentioned grooves 14 are formed at equal intervals in the member 18, and a support plane 22 for supporting a wafer peripheral edge (wafer outer periphery) 21 is formed at the bottom of each groove. As shown in FIG. 7, instead of the support portions 16A and 16B, as shown in FIG. 7, a wafer carrier 26 (hereinafter simply referred to as a wafer carrier) for supporting a wafer provided with support portions 24A and B composed only of the member 18 having the groove 14 is provided. The wafer carrier 26 is also used (see FIG. 8). In this case, the support portion 24A is provided below the horizontal center line of the wafer in the side wall 17A.
Are similarly provided on the side wall 17B.

In order to clean a wafer by using the wafer carrier 10, the wafer carrier 10 containing the wafer is put into the cleaning tank 27 containing the above-mentioned cleaning solution, immersed in the cleaning solution, and the cleaning solution is moved upward (Y shown in FIG. 9). (See FIG. 9). The same applies to the wafer carrier 26.

[0005]

The following problems have conventionally occurred. First, when the wafer is cleaned by immersing the wafer carrier 10 having the support portion 16 below the wafer carrier in a cleaning solution, dust generated during wafer cleaning due to friction between the support portions 16A and 16B and the wafer is generated. This is to adhere to the central surface (see FIG. 10). In this specification, the central surface of the wafer refers to the surface of the wafer other than the peripheral portion of the wafer, and the dots on the wafer surface shown in the drawings indicate dust adhering to the wafer surface. Second, when the wafer is cleaned by immersing the wafer carrier 26 having the support portion 24 on the side wall of the wafer carrier in the cleaning solution, the cleaning solution flowing toward the lower side of the support portion 24 becomes the wafer center side, that is, Since the fluid flows toward the inside of the support portion 24 as shown by an arrow W (see FIG. 11), dust generated by friction between the support portions 24A and 24B and the wafer during wafer cleaning adheres to the central surface of the wafer. (See FIG. 12). This flow is caused by the wafer carrier 10
But it was happening. Third, in the wafer carrier 26,
It is necessary to narrow the groove width of the support portion 24 so as to prevent the wafer from swinging in the horizontal direction during cleaning and contacting the adjacent wafers.
This means that when the wafer is taken out, the peripheral edge 21 of the wafer is easily caught in the groove 14 and it is difficult to take out the wafer. Note that the groove width needs to be narrower as the position of the support portion 24 is closer to the center line in the horizontal direction of the wafer.
The problem was prominent. In view of the circumstances as described above, an object of the present invention is to provide a wafer carrier for wafer cleaning that prevents dust generated from the carrier during cleaning from adhering to the wafer.

[0006]

In order to achieve the above-mentioned object, a wafer carrier for cleaning a wafer according to the present invention comprises a support portion for supporting a wafer with a vertical wafer surface, and the wafer supported by the support portion. Is a wafer carrier for cleaning the wafer by immersing the wafer in a cleaning liquid flowing upward, and a supporting portion provided on the wafer carrier,
The pair of rods extending in the horizontal direction perpendicular to the wafer surface and supporting and contacting the peripheral edge of the wafer is formed as a pair of rods constituting a lowermost support portion. , And on both sides of the wafer.

[0007] In order to prevent the adjacent wafers from coming into contact with each other and to prevent the position of the wafers from moving, the rod-like body is formed with, for example, protrusions and grooves. Preferably, the pair of rods constituting the lowermost support portion has an outer surface formed of an inclined surface inclined upward and outward.

The present inventor has proposed that the wafer carrier 26
Considering that the frictional force acting between the wafer peripheral edge 21 and the groove 14 of the support portion 24 is reduced,
The state of contact between the groove and the groove 14 was observed. FIG. 13 is a partially enlarged sectional view showing a contact state between the wafer peripheral edge 21 and the groove 14. The wafer peripheral edge 21 was in line contact with the groove bottom. In the present specification, the line contact is a point of contact between the wafer peripheral edge and a support plane,
For example, the angle between the tangent to the peripheral edge of the wafer at the contact point 28 in FIG. 13 and the support plane is 0 °. Then, the present inventor studied a shape of the supporting portion such that the line contact is changed to the point contact. In this specification, the point contact means that the angle formed between the tangent line of the wafer periphery and the support plane at the point of contact with the support plane of the wafer periphery is not 0 °, in other words, that they intersect. That is, preferably, the pair of rods constituting the lowermost support portion has a groove orthogonal to the rod, and inserts the wafer periphery in the groove so that the wafer periphery is supported at a point contact at the groove bottom. Has been. Thereby, the frictional force is significantly reduced.

[0009]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. Embodiment Example This embodiment is a preferred embodiment of the present invention. 1A and 1B are a perspective view and a side view showing a configuration of a wafer carrier 32 for cleaning a wafer according to the present embodiment, respectively. Wafer carrier 32 for wafer cleaning according to the present embodiment (hereinafter simply referred to as wafer carrier 32)
Differs from the conventional wafer carrier 26 in the shape of the supporting portion. In the present embodiment, the same components as those in the related art are denoted by the same reference numerals, and description thereof is omitted.

The support portion 34 is formed as a pair of rod-shaped members extending in the horizontal direction perpendicular to the wafer surface and in contact with and supporting the wafer peripheral edge 21, and just below the horizontal center line of the wafer, It is arranged so as to be located on both sides of the accommodated wafer. Further, the support portion 34 includes a plurality of equally spaced grooves 36 orthogonal to the longitudinal direction of the support portion 34. FIG. 2 is an enlarged cross-sectional view of the support portion 34 as viewed from the direction of arrows II-II (see FIG. 1A). Supporting parts 34A, B
On the lower side, an inclined surface 38 inclined outward and upward from the inside to the outside is formed so as to have a so-called oblique cut shape. The bottom surface of the groove 36 is flat. Also, the groove bottom is located at the wafer periphery (wafer periphery) in the groove.
21 is inserted, as shown in FIG.
1 is supported by the inner peripheral edge 38 of the groove bottom, that is, the wafer peripheral edge 21 is supported by point contact. The width of the groove 36 is slightly smaller than the width of the groove of the wafer carrier 26.

In order to clean a wafer using the wafer carrier 32, the wafer carrier 32 containing the wafer is placed in a cleaning tank 27 and immersed in a cleaning liquid. Next, the cleaning liquid is caused to flow upward (see FIG. 3) to clean the wafer. As a result, the cleaning liquid flowing toward the lower side of the support portion 34 flows along the outer side surface as shown by an arrow U (see FIG. 3), and flows along the inside of the support portion as in the related art. Never. Therefore, dust generated by the frictional force acting between the support 34 and the wafer does not flow along the inside of the support 34.

As a result, dust adheres only to the wafer surface at the peripheral edge of the wafer substantially vertically above the support portion 34 of the cleaned wafer surface (see FIG. 4), and the dust adheres to the central surface of the wafer. Absent. Further, since the wafer peripheral edge 21 and the groove bottom are in point contact with each other, the frictional force acting between the wafer peripheral edge 21 and the groove 36 is greatly reduced. Rim 21
Is not caught in the groove 36 and the wafer carrier 32
It is extremely easy to store and take out the wafer from the wafer.

[0013]

According to the present invention, the support portion provided on the wafer carrier is formed as a pair of rod-shaped members which extend in the horizontal direction perpendicular to the wafer surface and are in contact with and support the peripheral edge of the wafer. ing. Further, the pair of rods constituting the lowermost support portion are disposed immediately below the horizontal center line of the wafer and on both sides of the wafer. Thus, when a wafer is cleaned using the wafer carrier according to the present invention, dust generated during cleaning due to frictional force acting between the wafer and the support constitutes the lowermost support of the wafer surface. It adheres only to the wafer surface at the periphery of the wafer immediately above the pair of rods, and does not adhere to the other wafer surfaces.

[0014] Preferably, the pair of rods constituting the lowermost support portion has an outer surface formed of an inclined surface inclined upward and outward. Thereby, the cleaning liquid flowing toward the lower side of the pair of rods constituting the lowermost support portion flows along the outer surface of the support portion, and flows along the inner side of the support portion as in the related art. Never. Therefore, dust generated by the frictional force acting between the lowermost support portion and the wafer does not flow along the inside of the lowermost support portion, and the above-mentioned effect becomes more remarkable.

Preferably, the pair of rods constituting the lowermost support portion has a groove perpendicular to the rod, and inserts the wafer periphery into the groove, and supports the wafer periphery at the groove bottom by point contact. Have been to be. As a result, the frictional force acting between the wafer and the groove is significantly reduced, so that when the wafer is taken in and out of the wafer carrier, the peripheral edge of the wafer is hardly caught in the groove.

[Brief description of the drawings]

FIGS. 1A and 1B are a perspective view and a side view showing a configuration of a wafer carrier for cleaning a wafer according to an embodiment of the present invention, respectively.

FIG. 2 is an enlarged cross-sectional view of the support portion as viewed from the direction of arrows II-II.

FIG. 3 is a side view showing that a wafer is cleaned using a wafer carrier in the embodiment.

FIG. 4 is a side view showing that dust adheres only to a wafer surface at a peripheral portion of the wafer immediately above a supporting portion in the embodiment.

5A and 5B are a perspective view and a side view showing a conceptual configuration of a conventional wafer carrier for cleaning a wafer, respectively.

FIG. 6 is an enlarged view of a cross section taken along line II of FIG.

FIG. 7 is an enlarged cross-sectional view of a support portion of a conventional wafer carrier having a support portion on a side wall.

FIG. 8 is a side view showing a configuration of a conventional wafer carrier having a supporting portion on a side wall.

FIG. 9 is a side view showing that a wafer is cleaned using a conventional wafer carrier.

FIG. 10 is a side view showing that dust adheres to a central surface of a wafer in the related art.

FIG. 11 is a side view showing that a wafer is cleaned using a conventional wafer carrier.

FIG. 12 is a side view showing that dust adheres to a central surface of a wafer in the related art.

FIG. 13 is a partially enlarged cross-sectional view showing a contact state between a wafer peripheral portion and a groove.

[Explanation of symbols]

Reference numeral 10: wafer carrier, 12: orientation flat surface, 14: groove, 15A to F: holding part, 16
A, B ... support portion, 17A, B ... side wall, 18 ... member, 20 ... member, 21 ... wafer periphery, 22 ... support plane, 24A, B ... support portion, 26 ... wafer carrier , 27 cleaning tank, 28 contact point, 32 wafer carrier, 34 support, 36 groove, 38 inner peripheral edge.

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[Procedure amendment]

[Submission date] January 9, 1998

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0002

[Correction method] Change

[Correction contents]

[0002]

2. Description of the Related Art Conventionally, to clean a wafer with a cleaning liquid,
In general, a wafer is housed in a wafer carrier for wafer cleaning, the wafer carrier is immersed in a cleaning tank containing a cleaning liquid, a solvent is flown for cleaning, and then the wafer is exposed to isopropyl alcohol vapor to dry the wafer. . This is often done with automatic washing machines. As the cleaning liquid, for example, APM (ammonia water and hydrogen peroxide water)
And water), HPM (hydrochloric acid, hydrogen peroxide and water)
Mixture), BHF (buffered hydrofluoric acid), LE solution
(Mixed with hydrogen fluoride water and water
Liquid) and SPM (a mixture of sulfuric acid and hydrogen peroxide).
You. 5A and 5B are a perspective view and a side view showing a conceptual configuration of a conventional wafer carrier for cleaning a wafer, respectively. A conventional wafer carrier 10 for cleaning a wafer (hereinafter simply referred to as a wafer carrier 10) has a groove 1
Two supporting portions 16A, B with four are provided at the lower portion of the wafer carrier. Further, the wafer carrier 10 has a grooved holding portion 15A for holding the periphery of the upper half of the accommodated wafer.
To F are provided on each of the side wall 17A and the side wall 17B. The material of the wafer carrier 10 is, for example, quartz. A conventional wafer carrier for cleaning a wafer is shown in FIG.
As shown in FIG. 1, there are many cases where the orientation flat surface 12 is housed with the downward direction.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction contents]

The support portion 34 is formed as a pair of rod-shaped members extending in the horizontal direction perpendicular to the wafer surface and in contact with and supporting the wafer peripheral edge 21, and just below the horizontal center line of the wafer, It is arranged so as to be located on both sides of the accommodated wafer. Further, the support portion 34 includes a plurality of equally spaced grooves 36 orthogonal to the longitudinal direction of the support portion 34. FIG. 2 is an enlarged cross-sectional view of the support portion 34 as viewed from the direction of arrows II-II (see FIG. 1A). Supporting parts 34A, B
On the lower side, an inclined surface 38 inclined outward and upward from the inside to the outside is formed so as to have a so-called oblique cut shape. The bottom surface of the groove 36 is flat. Also, the groove bottom is located at the wafer periphery (wafer periphery) in the groove.
21 is inserted, as shown in FIG.
1 is supported by the inner peripheral edge 40 of the groove bottom, that is, the wafer peripheral edge 21 is supported by point contact. The width of the groove 36 is slightly smaller than the width of the groove of the wafer carrier 26.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] Explanation of sign

[Correction method] Change

[Correction contents]

[Description of Signs] 10 Wafer carrier 12 Orientation flat surface 14 Groove 15 A to F Holder 16
A, B ... support portion, 17A, B ... side wall, 18 ... member, 20 ... member, 21 ... wafer periphery, 22 ... support plane, 24A, B ... support portion, 26 ... wafer carrier , 27 cleaning tank, 28 contact point, 32 wafer carrier, 34 support, 36 groove, 38 inclination
Surface, 40 ... the inner periphery .

[Procedure amendment 4]

[Document name to be amended] Drawing

[Correction target item name] Figure 2

[Correction method] Change

[Correction contents]

FIG. 2

Claims (3)

[Claims] 1. A wafer carrier for cleaning a wafer, comprising: a support portion for supporting a wafer with a vertical wafer surface, and immersing the wafer supported by the support portion in a cleaning fluid flowing upward to clean the wafer. The support portion provided on the wafer carrier is formed as a pair of rod-shaped members extending in the horizontal direction perpendicular to the wafer surface and in contact with and supporting the peripheral edge of the wafer, and constitutes a lowermost support portion. Wherein the rod-shaped member is located on both sides of the wafer immediately below the horizontal center line of the wafer. 2. The wafer carrier for cleaning a wafer according to claim 1, wherein the pair of rods constituting the lowermost support portion has an outer surface having an inclined surface inclined outward and upward. . 3. A pair of rods constituting a lowermost support portion has a groove orthogonal to the rod, and inserts a wafer periphery into the groove to support the wafer periphery at a point contact at the groove bottom. The wafer carrier for cleaning a wafer according to claim 1 or 2, wherein: