JPS6187351A - Handler for carrying wafer - Google Patents

Abstract

PURPOSE:To obtain a compact handler, the length of hand arms of which is shortened, by turning a first arm member centering around a connecting point with the revolution of a second arm member, overlapping the first arm member on the second arm member and bringing the first arm member to a movable state in the direction of the side reverse to a previous state. CONSTITUTION:Hand arms 12 are rotated so as to be bent centering around shafts 11 with the revolution of arms 10 using shafts 9 as centers while other ends of the hand arms 12 are also turned similarly to a finger 5 centering around shafts 13 at that time. The hand arms 12 are overlapped on their midways, and paired arms are moved up to positions where paired arms mutually face rectilinearly, and rotated centering around the shafts 11 in the direction separate from a wafer cassette 6. Finally, the hand arms 10 and the hand arms 12 are extended in a straight line in the direction opposite to an original state, and the finger 5 is positioned so as to be overlapped to the upper sections of the hand arms 10 and 12. Accordingly, the length of the hand arm may be one fourth of the predetermined distance of movement of a wafer as compared to conventional handlers, and the extremely compact handler is manufactured.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a wafer transport handler, and more particularly to a wafer transport handler that is conveniently used when loading and unloading wafers from a carrier that stores a plurality of wafers.

Generally, the main body of the equipment that processes or measures wafers is equipped with a carrier that can store multiple wafers.6 The wafers are fed from the carrier to the main body of the equipment, and after processing or measurement is completed here, they are returned to the carrier. It is stored and sent along with the carrier to the next process.

Conventionally, belt conveyor-type conveyance devices and hand-type conveyance devices have been used to carry wafers in and out of carriers. FIG. 1 is a diagram schematically showing a known pantograph handler. This handler includes a hand arm 1 which is rotatable around a support 3 provided at one end, a hand arm 2 whose one end is also rotatably connected to the other end of the hand arm 1 via a shaft 4, At the other end of hand arm 2, there is a J! &
! The wafer supporting fingers 5 are connected to each other. Note that the handler has two hand arms 1 and two hand arms 2, each in pairs.

FIG. 1 shows a state in which the hand arm 1 and the hand arm 2 are extended in a straight line, and the finger 5 is positioned on the back side of a wafer 7 housed in a wafer cassette 6. On the other hand, FIG. 2 shows a state in which the finger 5 is retracted toward the shaft 3 with the position of the shaft 3 as a fixed point, and the wafer 7 is taken out from the wafer cassette 6. Here, hand arm 2 is arm 1 centered on axis 3.
According to the rotation of the hand arm 2, the hand arm 2 rotates so as to be bent about the axis 4, and at this time, the other end of the hand arm 2 also rotates about the axis 8 with respect to the finger 5. Eventually, hand arm 1 and hand arm 2 overlap and move to a position where the paired arms face each other in a straight line.

According to the handler configuration described above, the hand arm needs to have a length that is half the predetermined travel distance of the wafer. Furthermore, when the wafer is rotated for reasons such as feeding the wafer taken out from the carrier to the main body of the apparatus, hand arm 1 and hand arm 2 overlap, and the paired arms rotate in a state facing each other in a straight line. It is necessary to change the position of the wafer placed on top. This increases the area required for the operation of the handler.

In addition, the conventional handler must have a mechanism 11 that allows the hand arm 1 and the hand arm 2 to tilt at the same angle with respect to the fingers.

An object of the present invention is to provide a compact handler with a shortened hand arm length.

Still another object of the present invention is to provide a handler in which the area required for operations such as rotation of the handler can be significantly reduced by devising the bending type of the hand arm.

A preferred embodiment of the invention will now be described with reference to FIG. The handler of the present invention includes a hand arm lO which is rotatable about a shaft 9 provided at -b:ij, and one end of which is rotatably connected to the other end of the hand arm 10 via a shaft 11. The hand arm 12 is composed of a hand arm 12 and a wafer supporting finger 5 pivotally connected to the other end of the hand arm 12. In addition/\
The handler has a hand arm 10 and a hand arm 12.
Each has two pairs of them.

FIG. 3 shows a state in which the hand arm 10 and the hand arm 12 are extended in a straight line, and the fingers 5 are positioned on the back side of the wafer 7 housed in the wafer cassette 6. On the other hand, FIG. 4 shows a state in which the finger 5 is retracted toward the shaft 9 with the position of the shaft 9 as a fixed point, and the wafer 7 is taken out from the wafer cassette 6. Here, the hand arm 12 rotates so as to bend around the shaft 11 in accordance with the rotation of the arm 10 around the shaft 9, and at this time, the other end of the hand arm 12 also rotates around the shaft 13 with respect to the finger 5. and rotate. In the middle, arm lO and arm 12 overlap,
A position where the paired arms face each other in a straight line (
(See Figure 2) Move with ease.

In the handler of the present invention, the hand arm 12 is moved from the position shown in FIG.
It rotates around the shaft 11 in the desired direction. Finally, hand arm 10 and hand arm 12 extend in a straight line in the opposite direction to the state shown in FIG. 3, and finger 5 is positioned above hand arms 10 and 12 so as to overlap. Therefore, in the case of the handler of the present invention, compared to the conventional handler shown in FIG. 1, the length of the hand arm is only one-fourth of the predetermined travel distance of the wafer, making the handler extremely compact. Furthermore, as shown in FIG. 4, most of the arms 10 and 12 are located directly below the wafer 7 placed on the surface of the fin car 5, so the handler is rotated to move the wafer 7 in a desired direction. The required footprint is then extremely small.

Now, a mechanism that enables the operation of the hand arms 10 and 12 as described above will be explained with reference to FIG. 5.

The IklI9 is constructed integrally with the arm 10, and a pulley 14 is incorporated inside the shaft 9. On the other hand, the shaft 11 is composed of a pulley that is integrated with the arm 12, and a timing belt 15 is provided between the pulley 14 and the pulley 11.
The stake has been passed. Therefore, when the pulley 14 is rotationally driven, a driving force is transmitted to the pulley 11 via the timing belt 15, and in order to move the finger 5 linearly in the direction toward the shaft 9, the arm 1
The pulley 14 is arranged so that the inclination angle of 0 and the opening angle of the arms 10 and 12 always maintain a 1:2 relationship.
The driving force must be determined.

6 and 7 are a side view and a plan view, respectively, of an embodiment in which a wafer position detection mechanism is incorporated into a wafer handler of the present invention. As mentioned above, a plurality of wafers 7 are stored in the cassette 6, but in order to insert the finger 5 between the desired wafer 7 to be carried out and the adjacent wafer 7, it is necessary to accurately position the wafers. need to be detected.

Therefore, it is ingenious to use a wafer position detection mechanism built into the wafer handler. The basic configuration of this wafer position detection mechanism includes a laser source 16, a mirror 18 placed on the front side of the cassette 6, and a laser 20 emitted from the laser source 16 that is reflected toward the mirror 18. It has a half mirror 17 that transmits the reflected laser and a photosensor 19 that detects the laser that has passed through the half mirror 17. In order to eliminate the need for positional correction due to the difference in level between the finger 5 and the laser optical path, it is preferable to make the levels of the finger 5 and the laser optical path very close to each other. This is because lasers have excellent straightness and are therefore suitable for detecting the position of linear objects. For example, LE other than laser as a light source
When D or the like is used, the light from the light source spreads to some extent, so it is extremely difficult to detect that the desired wafer whose position is to be detected blocks the optical path using this spread light.

Another method is to view the cross section of the wafer using a TV camera, but when using a TV camera, the camera lens must be focused. However, the position of the wafers housed in the cassette/cassette varies considerably in the direction in which the wafers are taken in and taken out, making it impossible to achieve correct focusing, making it unsuitable for precise position detection. Additionally, TV cameras are expensive and extremely complex.

In short, the wafer position detection method using a laser not only has a linear optical path, so there is no influence from adjacent wafers above and below, but also does not require focusing, so it can be used in the direction of loading and unloading the stored wafers. There is no decrease in detection accuracy due to long-lasting problems at the P4 position.

Here, reference numeral 21 is a hand arm extension/contraction drive section for bending the hand arms 10 and 12 in order to extract the finger 5 from the cassette 6. Reference number 2
Reference numeral 2 denotes a handler rotation motor used when rotating the hand tool to change the direction of the wafer 7 placed on the surface of the finger 5.

Furthermore, reference numeral 23 is a handler lifting mechanism, which can change the height of the fingers 5 to a desired level in order to take out the wafer 7 stored in the cassette 6 at any position.

[Brief explanation of drawings]

Fig. 1 shows the conventional handler in an extended state, Fig. 2 shows the handler in Fig. 1 in a folded state, and Fig. 3 shows the handler of the present invention in an extended state. Figure 4 is a diagram showing the handler in Figure 3 in a folded state, Figure 5 is a diagram showing the drive mechanism of the arm of the handler shown in Figure 3, Figures 6 and 7 are 1A and 1B are a side view and a plan view, respectively, of an embodiment in which a wafer position sensing mechanism is incorporated into a handler of the present invention. 5-11 fingers 9-m-axis 10.12-m-hand arm 11.14--pulley 15-m-timing belt

Claims (1)

[Claims] a wafer support member configured to place a wafer on a surface; a pair of first arm members pivotally connected to the wafer support member; and a pair of second arm members rotatably connected at one end, and the first arm member is connected to a connecting point with the second arm member according to the rotation of the second arm member. 1. A wafer transfer handler, wherein the handler rotates about the second arm member, and after overlapping with the second arm member, is movable in a direction opposite to the front.