JPH0244149B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a semiconductor wafer scribing scratch forming apparatus for forming scribing scratches as starting points for cleavage at a portion of a semiconductor substrate to be cleaved.

(B) Prior Art Generally, in order to cleave a wafer, which is a raw material for semiconductor devices, a diamond scriber or the like is used to form a scribe mark as a starting point for cleavage at the desired part, and then the wafer is pressed by an appropriate means. Pressure is applied to separate the parts along the scribing scratches. When dividing the wafer by this cleavage, the starting point of cleavage is determined by the formation of the scribing scratches, so it is necessary to pay close attention to the formation of the scribing scratches.

According to the conventional scribing method, a scriber of a predetermined length is formed on one edge of a wafer by sweeping the scriber to the end thereof. However, since a scriber or the like is used to sweep the wafer to the end of the edge where a scribing scratch is to be formed, a composite force C of the scriber's stylus load A and tensile force B is applied to the wafer, as shown in Figure 4. Furthermore, the corner of the edge of the wafer where the scribing scratches have been formed may be chipped when the scriber is swept. In this case, when a pressing force is applied using the chipped scribe mark as a starting point for cleavage in the subsequent dividing step, cleavage often occurs from a region other than the desired cleavage, resulting in a problem of variations in element shape.

If a scribing scratch is formed on a wafer having a semiconductor laser structure using the above method and the wafer is divided using the scribing scratch as a starting point for cleavage, the above problem occurs and each element is formed with a different shape.
The laser oscillation threshold current changes based on the fact that the resonator wavelength of each element is different. That is, it is very difficult to manage the characteristics, resulting in a problem of lower yield.

(C) Objective The object of the present invention is to provide a semiconductor wafer scribing scratch forming apparatus that can accurately form scribing scratches that are starting points for cleavage and eliminates problems during the formation.

(D) Structure The semiconductor wafer scribing scratch forming apparatus according to the present invention is a semiconductor wafer scribing scratch forming apparatus that forms a scribing scratch as a starting point for cleavage at one edge of a semiconductor wafer on which devices are formed. A workbench for fixing a semiconductor wafer, an aluminum foil that covers the semiconductor wafer by exposing only the edge of one side where a scribing scratch is to be formed, and a sweeping movement from the aluminum foil to the edge of the one side to form a scribing scratch. and a stop table that contacts one edge of the semiconductor wafer and is installed higher than the surface of the semiconductor wafer so that the scriber that has formed the scratches can ride on it.

(E) Embodiments FIG. 1 is a perspective view of an embodiment of a semiconductor wafer scribing scratch forming apparatus according to the present invention.

In the figure, reference numeral 10 denotes a wafer on which predetermined devices are formed, and in this embodiment, a substantially rectangular wafer will be described as an example. 20 is a movable table 20 equipped with a vacuum chuck 21, and the wafer 10 is suctioned and fixed to a predetermined position on the upper surface of the movable table 20. Legs 22 each having a through hole are disposed at each corner of the lower surface of the movable table 20, and are disposed in parallel with the opposing edge of the movable table 20 at a predetermined distance. The leg portion 22 is fitted into the rail 23 so as to be freely movable. 30 is a diamond scriber (hereinafter referred to as scriber) as a scriber for forming scratches. A diamond needle 31 is provided at the tip of a mounting member 32 attached at a predetermined inclination to this, and is placed at a predetermined position above the movable table 20.

40 is an aluminum foil formed with a predetermined thickness;
It is attached so as to cover the upper surface of the wafer 10 fixed on the movable table 20.

Reference numeral 50 denotes a substantially cubic stop, which is disposed close to the portion of the wafer 10 where scribing scratches are to be formed.

Next, a method for forming scratches on a semiconductor device according to the first embodiment will be described below. (See Figure 2).

The wafer 10 is placed on the movable table 20 by abutting against a stop table 50 disposed close to the side of the movable table 20, which is a workbench, and the wafer 10 is transferred to the movable table 20 by the vacuum chuck 21.
Fix it by adsorption.

For example, mark the surface of the wafer 10 so that the portion where the scribing scratch is to be formed (near the edge portion 11) is exposed.
Attach aluminum foil 40 of about 15 μm as shown.

The scriber 30 is dropped relatively slowly onto the aluminum foil 40 on the side where the wafer 10 is not exposed using a driving means (not shown).

From here, the scriber 30 is swept at a predetermined speed toward the exposed portion of the wafer 10.

When the diamond needle 31 of the scriber 30 is positioned before reaching the end of the edge 11 of the wafer 10 (arrow c section in FIG. 2), the scriber 3
The mounting member 32 of No. 0 comes into contact with the edge of the stop table 50, and the scriber 3 is moved from the wafer 10 onto the stop table 50.
Since 0 moves, the formation of the scribing scratches is stopped. On the other hand, the scriber 30 on the stop table 50 rises at a predetermined position.

Hereinafter, the movable table 20 is driven by a drive device not shown, and the movable table 20 is moved to the rail 2.
3 in the direction of arrow a in FIG. 1, and the scriber 30 is also moved in the direction of arrow b in FIG. As the movable table 20 and the scriber 30 repeat the same operations as described above, scribing scratches are sequentially formed and the process is completed.

Therefore, in the above process, before reaching the end of the edge part 11, for example, 0.25~
A position of about 0.5 μm is desirable, but it is preferable to set this value appropriately depending on the scriber sweep speed, needle load, wafer rigidity, etc.

Embodiment FIG. 3 corresponds to FIG. 2, and shows a stop table 50 having a different shape.

The stop table 50 shown in the figure is the same as the stop table 50 shown in FIG. 2, with an inclined surface 51 having a predetermined angle of inclination formed on the upper part thereof. The stop table 50 has its inclined surface 51 in contact with the edge 11 of the wafer 10 with a predetermined step difference.

In the above process, in the second embodiment, when the mounting member 32 of the scriber 30 comes into contact with the inclined surface 51 of the stop table 50, it floats above the surface of the wafer 10 and moves upward along the inclined surface 51. That will happen.

According to the second embodiment, an effect can be obtained in that the scriber 30 can be moved more smoothly than the first embodiment.

(f) Effects As detailed above, this invention prevents the formation of scribing scratches to the end of the wafer, thereby preventing chipping of the edge corners of the wafer, and when dividing the wafer along the scribing scratches in a subsequent process. It is also possible to cleave accurately from the starting point. Therefore, based on the fact that variations in element shape can be minimized, product characteristics can be easily managed and yields can be improved. Further, since the stop position of the scriber is set by a stop table having a predetermined shape, there is no need for a position detection sensor or the like to detect the position of the scriber.

Further, the semiconductor wafer scribing scratch forming apparatus according to the present invention is particularly effective when applied to, for example, a wafer having a semiconductor laser structure.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a semiconductor wafer scribing scratch forming apparatus according to an embodiment of the present invention. FIG. 2 is an explanatory diagram showing the sweeping movement of the scriber 30 according to the first embodiment, FIG. 3 is an explanatory diagram showing the sweeping movement of the scriber 30 according to the second embodiment, and FIG. 4 is an explanatory diagram showing the sweeping movement of the scriber 30 according to the second embodiment. 3 is an explanatory diagram showing the load of the scriber 30. FIG. DESCRIPTION OF SYMBOLS 10... Wafer, 11... Edge part, 12... Scratch, 20... Movable table, 30... Diamond scriber, 50... Stop table, 51... Inclined surface.

Claims (1)

[Scope of Claims] 1. A semiconductor wafer scribing scratch forming apparatus that forms a scribing scratch as a starting point for cleavage on one side edge of a semiconductor wafer on which a device is formed, comprising: a work table for fixing the semiconductor wafer; An aluminum foil that covers a semiconductor wafer exposing only the edge of one side where a scratch is to be formed; a scriber that is swept from the aluminum foil to the edge of one side to form a scribe scratch; 1. A device for forming scribe scratches on a semiconductor wafer, comprising a stop table that contacts one edge of the semiconductor wafer for a scriber to ride on, and is installed higher than the surface of the semiconductor wafer. 2. The semiconductor wafer scribing scratch forming apparatus according to claim 1, wherein the stop table is inclined upward in the direction of sweeping movement of the scriber.