JPS609347B2 - Method for separating chipped pellets around semiconductor wafers - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for efficiently separating edge pellets of a scribed or diced semiconductor wafer.

Generally, a method is adopted in which a disk-shaped semiconductor wafer with a predetermined P-N joint is scribed or diced in the X-axis direction and the Y-axis direction at right angles to each other to divide it into rectangular small pellets. ing.

In this case, since the semiconductor wafer is disk-shaped, the peripheral part does not form a perfectly rectangular pellet, and because it does not have a predetermined size, this part is separated and removed before use. . That is, as shown in FIG. 1, for example, when manufacturing small semiconductor elements such as transistors and diodes, a predetermined P-N junction is formed throughout the disk-shaped semiconductor wafer, and then the above-mentioned semiconductor A wafer 1 is attached to an adhesive tape 2.

This adhesive tape 2 is scribed or diced in the X-axis direction and the Y-axis direction so as to be perpendicular to each other using a predetermined machine or the like to form a semiconductor pellet 3 in the form of a small piece.

In this case, the surrounding chipped pellets 4 shown by hatching cannot be used and must be removed, but the following method is generally being explored. That is, the semiconductor wafer 1 cut on the adhesive tape 2 is soaked together with the adhesive tape 2 in an organic solvent such as trichloride, and after separating the individual semiconductor pellets 3 and chipped pellets 4 from the adhesive tape 2, an appropriate There is a method of spreading the pellets on a tray and manually sorting the square semiconductor pellets 3 from irregularly shaped chipped pellets using a brush or the like, or a method of sorting them using a sieve with a predetermined mesh. There is a method of separating the semiconductor pellets 3 and chipped pellets 4 using a vacuum chuck, tweezers, etc. in a state where the semiconductor pellets 3 are aligned as shown in the figure.

However, in the first method, the work is complicated and time-consuming because it is carried out manually using a brush, etc., and in the second method, vibration is applied to the sieve, which causes collisions between semiconductor pellets. It is easy to damage the corners and it is difficult to completely separate odd-shaped pellets from square pellets. Since the method is separated into individual parts, it takes a lot of time and is inefficient.

The present invention has been made based on the above-mentioned circumstances, and the present invention is a method for separating chipped pellets around a semiconductor wafer, in which a square semiconductor pellet and an irregularly shaped chipped pellet can be easily and reliably separated without causing damage. The purpose is to provide a method.

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

In FIG. 2, the diameter D of the semiconductor wafer is generally finished with high precision. Therefore, once the dimensions of one semiconductor pellet 3 are determined at the design stage, the number and arrangement pattern of the semiconductor wafer 1 can be determined. are determined visually, and their errors are extremely small even between multiple semiconductor wafers. Therefore, a mask plate 5 is prepared in a shape that matches the arrangement pattern of the maximum number of rectangular semiconductor pellets 3, that is, with the chipped pellets 4 at the periphery of the semiconductor wafer removed.

FIG. 3 shows the outer shape of this mask plate 5, and the plate thickness is 0.1
It is formed from a thin stainless steel plate, etc. that is thinner than the skin. Next, as shown in FIG. 4, this mask plate 5 is attached to an adhesive tape 6 having a stronger adhesive strength than the adhesive tape 2 to which the semiconductor wafer is attached, and then the semiconductor wafer 1 is attached as shown in FIG. Lay them out according to the arrangement pattern of Novelette 3. In this way, the chipped pellets 4, 4 on the periphery of the semiconductor wafer 1 that deviate from the outer shape of the mask plate 5 are attached by applying pressure in the direction of the arrow to the adhesive tape 6 with strong adhesive strength, and then,
If the adhesive tapes 2 and 6 are peeled apart in the direction of separation, the result will be as shown in FIG.

That is, except for the arrayed part of the rectangular semiconductor pellets on which the mask plate 5 is superimposed, the chipped pellets 4, 4 in the periphery are attracted to the adhesive tape 6 side with strong adhesive strength, and the adhesive tape 6 with weak adhesive strength is attached to one side. On the second side, only the square semiconductor pellet 3 except the chipped pellet 4 remains.

As is clear from the above description, according to the present invention, chipped pellets around the semiconductor wafer can be easily and quickly removed in a state where the semiconductor wafer has not been separated, and moreover, collisions between the semiconductor pellets can be avoided. Since no damage is caused, it can contribute to improving the yield.

Although the materials of the adhesive tapes 2 and 6 are not mentioned in the embodiments of the present invention, it is convenient to use transparent adhesive tapes for alignment purposes, and it goes without saying that the materials are not particularly limited.

[Brief explanation of the drawing]

Fig. 1 is a plan view of a semiconductor wafer attached to an adhesive tape, Fig. 2 is an enlarged plan view showing the arrangement of semiconductor pellets on the semiconductor wafer, and Fig. 3 is a plan view of a semiconductor wafer attached to an adhesive tape. A plan view of the mask plate, FIG. 4 is a side view of the mask plate attached to an adhesive tape and facing a semiconductor wafer on the other adhesive tape, and FIG. 5 is a side view of the mask plate attached to the semiconductor wafer. FIG. 6 is a side view of the mask plate superimposed on the adhesive tape attached to the adhesive tape side. It is a side view which shows the state in which the chipped bullet which should be removed remains on the side. DESCRIPTION OF SYMBOLS 1... Semiconductor wafer, 2, 6... Adhesive tape, 3... Semiconductor pellet, 4... Chipped pellet, 5... Mask plate. Multi-function 2 drawings 3 drawings 4th drawing 0 drawings

Claims (1)

[Claims] 1. A mask plate is formed in accordance with the arrangement pattern of rectangular semiconductor pellets to be individually separated on a semiconductor wafer, and this mask plate is coated with adhesive force stronger than the adhesive force of the adhesive tape to which the semiconductor wafer is attached. After adhering to the adhesive tape having the semiconductor wafer, the mask plate is overlapped in accordance with the arrangement pattern of the semiconductor pellets, and chipped pellets around the semiconductor wafer are adsorbed to the side of the adhesive tape with strong adhesive strength and separated. A method for separating chipped pellets from the periphery of a wafer.