JPH0671040B2 - Wafer cassette transfer mechanism - Google Patents

Description

The present invention relates to a wafer cassette transfer mechanism, and more particularly, to a mechanism for preventing chipping of the edge of a wafer caused by vibration of the wafer in a cassette. The present invention relates to a wafer cassette transport mechanism.

"Prior Art" A plurality of semiconductor wafers are stored in a storage device generally called a wafer cassette, and transportation in each process and between processes is performed in the storage device. The wafer cassette has a plurality of guide grooves inside, and the wafer is engaged in this groove to stand and hold it, but this groove is the same for loading and unloading wafers and wafers of various thicknesses. The width of the wafer is sufficiently wide for reasons such as the use of the cassette. Therefore, the wafer vibrates during transportation of the wafer cassette. When this transfer is performed manually, vibration during transfer is not a problem, but when mechanical transfer is performed as in the automatic transfer of recent years, the vibration causes the photoresist film formed on the wafer surface. , CV
It was found that there are problems such as damage at the wafer edge such as the D film and the generation of dust by them.

FIGS. 1 and 2 are external views of a conventional wafer cassette transfer mechanism. In the example of FIG. 1, a carrier 2 fitted to a guide rail 1 is attached to a wafer cassette holding latch 3,
A wafer cassette 5 in which a plurality of semiconductor wafers 6 are stored is held by these latches and transported. In the example of FIG. 2, a self-propelled carrier 7
The wafer cassette 5 is transported with the wafer cassette 5 placed thereon. The automatic transport system shown in Fig. 1 and Fig. 2 inevitably generates vibration to some extent during acceleration / deceleration or operation, which causes the edge of the wafer engaging with the groove of the wafer to collide with the groove. Garbage is generated from that part. The dust may be due to components of various films provided on the wafer, chipping of the wafer itself, or the like, but if these dusts adhere to the element region of the wafer, they may cause element defects in subsequent processing steps.

In order to solve the problem that the wafer comes into contact with the partition wall of the cassette when the wafer is moved and scratches or chipping occurs on the processing surface, the height of the legs of the cassette is changed by about 5 to 10 mm. As a structure, it is described in Japanese Patent Laid-Open No. 59-61942 that the partition plate is inclined so that one surface of the wafer is not in contact with the partition wall of the cassette.

Stacking such cassettes with wafers stored inside is unstable, and there is an extra space on one leg, which necessitates a wasted space for storing the cassettes themselves and also for transporting. When the carrier tries to hold the cassette by the holding ratchet, there is a problem that an extra mechanism for catching an inclined object is required.

In addition, it is necessary to provide a plurality of support plates for holding the wafers obliquely on the basket for wafer processing.
-120643 publication. This basket is
Since the support plate is obliquely fixed, an extra space is required to store the same number of wafers.

Further, Japanese Patent Laid-Open No. 56-120124 discloses that when replacing a wafer with a heat-resistant boat, the heat-resistant boat is placed on an inclined table so that the wafer is aligned in the tilt direction and the work of the wafer is automated. ing. This method requires a special device for mounting the heat-resistant boat,
No consideration was given to the problems in transporting the wafer.

Japanese Utility Model Publication No. 57-58764 discloses a jig body for arranging a predetermined number of wafers. This is because the support rods provided with grooves for fitting the peripheral edge of the wafer face each other with a required width, and both ends of the support rods are pivotally held by the support frames, and the mounting angle of each support rod and the support frame is adjusted. Although the alignment angle of the groove is adjustable, it is for facilitating the loading and unloading of the wafer, and has a mechanism for inclining the groove provided in the support rod. The way does not consider any problems during transportation.

[Problems to be Solved by the Invention] The present invention is a wafer cassette in which a wafer is hardly vibrated in a wafer cassette even when a conventional wafer cassette is used, only by providing a simple tilting means having a cassette holding function to a transfer mechanism. An object is to provide a transport mechanism.

[Means for Solving the Problems] The present invention provides a wafer cassette transport mechanism that accommodates most of the wafer while having a plurality of guide grooves that are wide relative to the thickness of the semiconductor wafer and that accommodates the peripheral edge of the wafer. In a semiconductor manufacturing process, a guide rail that connects the processes within and between the processes, a carrier that engages with the guide rail to convey the cassette, and a carrier that is provided on the carrier and has a cassette holding function.
The above-mentioned object is achieved by providing a tilting means which is set at a degree (horizontal) and is set at a tilt of 5 degrees to 45 degrees during conveyance after holding the cassette.

A feature of the present invention is a wafer cassette transport mechanism for transporting a wafer cassette containing a semiconductor wafer,
This semiconductor wafer has a mechanism for holding the wafer cassette such that the semiconductor wafer has a certain inclination with respect to the direction of gravity. It is desirable that the inclination of the cassette is regulated so that the inclination of the wafer is 5 degrees to 45 degrees. In particular, when the wafer is in the range of 10 degrees to 25 degrees, the most preferable characteristics are obtained in relation to the acceleration applied to the cassette.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 3 is an external view of an embodiment of the present invention.

[Embodiment 1] FIG. 3 is an example in which the present invention is applied to the transport mechanism shown in FIG.

The carrier consists of a trolley part 8 which fits on the guide rail 1 and a base 9 on which the latches 3, 4 holding the cassette are based. Here, the latches 3 and 4 constitute means having a function of holding the cassette, and the base 9 constitutes inclination means having a function of changing an angle with respect to the carriage 8.
This angle is set to 0 degree when the wafer cassette 5 is attached and detached by the holding latches 3 and 4, and is set to an inclination of 10 degrees in the present embodiment after holding the cassette. As a result, the wafer has an inclination of about 10 degrees with respect to the direction of gravity,
The back surface of the wafer is in close contact with one surface of the groove of the cassette, so that it does not vibrate in the groove when the carrier is operated or stopped.

[Advantages of the Invention] The present invention relates to a semiconductor wafer cassette transporting mechanism between semiconductor manufacturing steps which requires a high degree of cleanliness, and a guide rail provided between these steps to provide dust on the wafer surface. The wafer is vibrated in the guide groove by holding it in a cassette carrier that stores the wafer in a substantially gravity direction in which dust and dirt are unlikely to adhere, and further by holding the cassette at 5 to 45 degrees during transportation. It is possible to uniformly apply an inclination that causes almost no damage or generation of dust to all the wafers stored in the cassette. Also, since the tilting of the cassette is performed by the tilting means provided on the carrier, the cassette removed from the carrier keeps the stored wafer in a substantially gravity direction on a horizontal holding table, which is convenient for keeping cleanliness. In addition, it is convenient for handling in semiconductor manufacturing equipment.

[Brief description of drawings]

1 and 2 are external views of a conventional wafer cassette carrying mechanism, and FIG. 3 is an embodiment in which the present invention is applied to the wafer cassette carrying mechanism of FIG. In the figure, 1 ... Guide rail, 2 ... Carrier, 3,4 ... Latch for holding wafer cassette, 5 ... Wafer cassette, 6 ... Wafer, 7 ... Self-propelled carrier, 8 ... Cart Part, 9 ... Base.

Claims (1)

[Claims] 1. A wafer cassette transporting mechanism for arranging a plurality of guide grooves which are wider than the thickness of a semiconductor wafer and which accommodates the peripheral edge of the wafer, and which accommodates most of the wafer, in a semiconductor manufacturing process. And a guide rail that connects the steps, a carrier that fits on the guide rail to convey the cassette, and a carrier provided in the carrier that has a cassette holding function and is set to 0 ° when the cassette is attached or removed. Sometimes 5
A wafer cassette transfer mechanism comprising: an inclining means set to an inclination of 45 degrees to 45 degrees.