JPH05206251A - Alignment equipment for orientation flat - Google Patents

Abstract

PURPOSE:To improve precision of orientation flat alignment in a structure of an equipment for arranging the position of orientation flats of wafers. CONSTITUTION:The title equipment is provided with the following; a carrier stand 11, a driving roller 12 which is in contact with the periphery of a wafer 1 and rotates it, two retaining parts 13, 14 whose upper surfaces are equal in height, and a vertical movement means 15 which moves the retaining parts 13, 14 up and down. Firstly, a wafer carrier 2 which vertically retains a plurality of wafers 1 is mounted on the carrier stand 11, the wafer 1 is rotated by the driving roller 12, and roughly aligned in the manner in which an orientation flat 1a is positioned on e lower side. Secondly, two retaining parts 13, 14 retain both sides of the central part of the orientation flat 1a and lift up the wafer 1, and descend after the orientation flat 1a is set to be horizontal, and the wafer 2 is again vertically retained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of an orientation flat aligning device for aligning the positions of orientation flats (hereinafter referred to as orientation flats) of a wafer in a semiconductor device manufacturing process.

In the wafer processing step of the semiconductor device manufacturing process, it is generally performed to position the wafer in a predetermined direction with the orientation flat as a reference before loading the wafer into the processing apparatus. This is referred to as orientation flat alignment, and when the wafer processing apparatus is a batch system, generally, a large number of wafers accommodated in a general-purpose wafer carrier (cassette) for inter-apparatus transportation are collectively aligned.

[0003]

2. Description of the Related Art An example of a conventional orientation flat aligning device will be described with reference to FIG. FIG. 2 is an explanatory diagram of a conventional example,
(a) → (c) shows the process of orientation flat matching in order.
In the figure, the same parts as those in FIG. 1 are designated by the same reference numerals. This device comprises a carrier table 11, a driving roller 12 and the like. A wafer carrier 2 holds a large number of wafers 1 upright, and each wafer 1 is a wafer carrier 2
It is supported in contact with the inner inclined surfaces 2a facing each other.

The drive roller 12 is rotated around a horizontal rotation axis by a rotation means (not shown) including a motor and the like.
The drive roller 12 has a length capable of contacting all the wafers 1 accommodated in the wafer carrier 2. The height of the drive roller 12 is set so that the wafer carrier 2
It is adjusted such that the gap between the orientation flat 1a in the horizontal state and the orientation flat 1a when placed at a predetermined position 11 is substantially zero.

With this device, orientation flat alignment is performed as follows. First, while the drive roller 12 is being rotated, the wafer carrier 2 accommodating a large number of wafers 1 having random orientation flats 1a is set at a predetermined position on the carrier base 11 from above the orientation flat aligning device. The outer periphery of the wafer 1 comes into contact with the drive roller 12 and is lifted from the wafer carrier 2 to rotate, but when the orientation flat 1a becomes substantially horizontal on the lower side, the outer periphery of the wafer 1 comes into contact with the inclined surface 2a of the wafer carrier 2. Rotation stops.

[0006]

In such a conventional apparatus, even if the apparatus is adjusted with high accuracy, sufficient orientation flat alignment accuracy is obtained under the influence of variations in dimensions of the wafer and wafer carrier. There was a problem that there was not. If the orientation flat alignment accuracy is not sufficient, for example, an automatic wafer handling device that detects the presence or absence of a wafer in the orientation flat portion may cause a detection error.

It is an object of the present invention to solve such a problem and to provide an orientation flat aligning apparatus capable of collectively performing highly accurate orientation flat alignment on a large number of wafers held upright on a wafer carrier. To do.

[0008]

According to the present invention, the object is to provide [1] two support parts having an equal upper surface height and vertical moving means for moving the support parts up and down. An orientation flat alignment device characterized in that the two supporting portions are configured to rise from below the wafer held upright and contact the orientation flat of the wafer to lift the wafer. ,
[2] In addition to the above [1], an orientation which is characterized in that it has a driving roller that comes into contact with the outer periphery of the wafer held upright and rotates the wafer until the position of the orientation flat is on the lower side. This is achieved by using a flat alignment device.

[0009]

According to the present invention, two wafers, which are held upright on the wafer carrier, are pre-aligned by the prior art so that the orientation flat has a posture relatively close to the horizontal under the wafer in advance. The support part of supports at two points on the orientation flat and lifts. Since the heights of the upper surfaces of the two support portions are equal, when the orientation flat is inclined, only one of the support portions first comes into contact with the orientation flat. The inclination of the orientation flat is gradually corrected as the support portion rises, and becomes horizontal when the other support portion comes into contact with the orientation flat. Therefore,
Even if the precision of the pre-alignment is rough, it is possible to perform highly accurate orientation flat alignment that cannot be obtained by the conventional technique.
If the wafer is lifted up even slightly, it means that the two support parts are in contact with each other.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an orientation flat aligning device according to the present invention will be described with reference to FIG. FIG. 1 is an explanatory view of an embodiment of the present invention, in which (a) → (c) shows the process of orientation flat alignment in order. In the figure, 1 is a wafer, 1a is an orientation flat of the wafer 1, 2 is a wafer carrier, 2a is an inclined surface of the wafer carrier 2, 11 is a carrier base, 12 is a drive roller, 13 and 14 are supporting portions, and 15 is a vertical movement. It is a means. Of these, 11 to 15 are components of the orientation flat alignment device.

A large number of wafer carriers 2 (for example, 25 wafers)
The wafer 1 is held upright, and the upper and lower surfaces are open. Each wafer 1 is supported in contact with the opposing inclined surfaces 2a inside the wafer carrier 2.

The drive roller 12 is rotated around a horizontal rotation axis by a rotation means (not shown) including a motor and the like.
The drive roller 12 has a length capable of contacting all the wafers 1 accommodated in the wafer carrier 2. The height of the drive roller 12 is set so that the wafer carrier 2
It is adjusted so as to form a slight gap with the orientation flat 1a in the horizontal state when it is placed at a predetermined position of 11.

The supporting portions 13 and 14 are connected in parallel with the driving roller 12 so as to face each other with the driving roller 12 interposed therebetween. This support
13 and 14 have such a length that they can contact all the wafers 1 accommodated in the wafer carrier 2. These are moved up and down by the vertical moving means 15 (for example, an air cylinder),
The heights of these tops are always equal.

With this device, orientation flat alignment is performed as follows. First, the wafer carrier 2 containing a large number of wafers 1 in which the orientation flats 1a are randomly placed in a state in which the supporting portions 13 and 14 are lowered downward and the drive roller 12 is rotated.
Is set at a predetermined position on the carrier base 11 from above the orientation flat aligning device. The outer periphery of the wafer 1 comes into contact with the drive roller 12 and is lifted from the wafer carrier 2 to rotate. Rotation stops. At this time, the orientation flat 1a is slightly inclined with respect to the horizontal (this inclination is allowed up to about 5 °). Here, the rotation of the drive roller 12 is stopped.

Next, the supports 13 and 14 are raised. When one of these contacts the orientation flat 1a, the other does not contact. This state is shown in FIG. As the wafer 1 is further raised, the posture of the wafer 1 is gradually corrected, and the support portions 13 and
The orientation flat 1a becomes horizontal when 14 contacts the orientation flat 1a. This state is shown in FIG. 1 (b). Then supports 13 and 14
When is lowered, the wafer 1 is held upright on the wafer carrier 2 while the orientation flat 1a is kept horizontal. This state is shown in FIG. 1 (c).

The present invention is not limited to the above embodiments, but can be implemented with various modifications. For example,
The present invention is effective even for a device provided with a pre-alignment mechanism different from the drive roller 12. Further, the pre-alignment mechanism is not required in the apparatus for aligning the orientation flat of the wafer held upright in the pre-aligned state.

[0017]

As described above, according to the present invention, it is possible to provide an orientation flat aligning device capable of collectively performing highly accurate orientation flat alignment on a large number of wafers held upright on a wafer carrier. ..

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an example of the present invention.

FIG. 2 is an explanatory diagram of a conventional example.

[Explanation of symbols]

 1 Wafer 1a Orientation flat (orientation flat) 2 Wafer carrier 2a Inclined surface 11 Carrier stand 12 Drive roller 13, 14 Support 15 Vertical movement means

Claims (2)

[Claims] 1. Two support parts (13, 1) having an upper surface having the same height.
4) and vertically moving means for vertically moving the supporting portion (13, 14)
(15) and a wafer (1) in which the two support portions (13, 14) are held upright.
1. An orientation flat alignment device, characterized in that it is configured to rise from below and contact the orientation flat (1a) of the wafer (1) to lift the wafer (1). 2. A drive roller (12) for rotating the wafer (1) in contact with the outer periphery of the wafer (1) held upright until the orientation flat (1a) is located on the lower side. The orientation flat alignment device according to claim 1, wherein