JP2680453B2 - Dicing method - Google Patents

Description

The present invention relates to a dicing method, and more particularly to a dicing method for cutting a brittle material such as a semiconductor wafer.

[Conventional technology]

Conventionally, a dicing device for cutting a silicon wafer into semiconductor chips performs a wafer cutting process by rotating a dicing blade at a high speed. At the time of cutting, cutting water is applied to the blade and the wafer is cut while being washed with cleaning water. Carry out the work. Cutting water reduces cutting resistance and cleans the blade to remove dirt caused by cutting chips during cutting.
Further, the cleaning water directly cleans the wafer to remove dirt such as chips and the like adhering to the wafer, thereby maintaining the cleanliness of the wafer.

There are roughly two types of dicing processing, up-cutting and down-cutting, and FIG. 4 is an explanatory view showing a processing locus when down-cutting dicing processing is performed in the case of a moving cutting head. In FIG. 4, first, the wafer 10 is cut from the left to the right along the processing line 12A indicated by the solid line while supplying cutting water and cleaning water.
After the cutting of the processing line 12A, while supplying cutting water and cleaning water, the wafer is indexed in the Y direction by a predetermined amount as shown by a broken line 14A in order to cut the next processing line 12B. The wafer 10 is cut along the processing line 12B. At this time, the cut line 12A that was previously cut by the cutting water supplied when cutting the cut line 12B
Simultaneously clean the dirt in and around the groove. Cutting is performed by repeating such work.

[Problems to be solved by the invention]

However, in the conventional dicing method, since the last cut line is washed only once at the time of cutting, it is possible to completely remove dirt such as powdery chips attached to the cut groove and its periphery. There is a drawback that cannot be done.

Also, during the dicing process, the cut line check that automatically measures and displays the width of the cutting groove, the amount of chipping, the center deviation, etc. with a microscope etc., suspends the cutting temporarily, and blows air on the upper surface of the wafer to dry it. Observe. For this reason, the line cut immediately before the temporary stop is washed only once at the time of cutting, and the removal of dirt becomes insufficient. If the wafer is dried with dirt such as chips adhered, the chips harden in the adhered state and cannot be removed by any cleaning.

The present invention has been made in view of the above circumstances, and provides a dicing method capable of reliably removing dirt such as chips adhering to and around the cutting line of a wafer during cutting during cutting. With the goal.

[Means for solving the problem]

The present invention, in order to achieve the above object, a cutting head is provided with a dicing blade rotatably, a nozzle is provided in the cutting head, while cleaning the dicing blade and the wafer with cutting water ejected from the nozzle. In a dicing machine that cuts a wafer into chips along a predetermined cut line with a dicing blade, after cutting the wafer along one cut line,
While cutting and feeding the wafer mounting table or the cutting head by a predetermined amount, the dicing blade is obliquely returned to move to the cutting start position of the next cut line so as to form a zigzag feed, and cut a plurality of next cut lines, Immediately after the cutting of the last cut line in the same direction is completed or immediately after the wafer is cut along any cut line, the dicing blade is placed along the line of the wafer cut immediately before the cutting is completed or immediately before the cutting is stopped. In addition, the line is cleaned again with cutting water while moving the wafer mounting table or the cutting head.

[Action]

According to the present invention, when the cutting along the cut line in the same direction is repeated, after cutting along one cut line, the dicing blade is obliquely returned while indexing and feeding a predetermined amount to cut the next line. It is moved to the start position and the previous line is washed with cutting water that accompanies the cutting of the next line. Then, when the cutting of the last cut line in the same direction where the cutting of the next line is not performed is finished,
Alternatively, only when the cutting is temporarily stopped, the wafer mounting table or the cutting head is moved so that the dicing blade follows the line cut immediately before the end of cutting or immediately before the temporary stop. Then, when moving, dirt such as cutting chips adhering to the groove on the line and its periphery is washed and removed again with cutting water. As a result, the cleanliness of the wafer after cutting can be improved.

〔Example〕

Hereinafter, preferred embodiments of a dicing method according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a side view showing the periphery of a dicing blade which is a main part of a dicing machine used in the dicing method according to the present invention, and FIG. 2 is a plan view of the periphery of the dicing blade. As shown in FIG. 1, the dicing blade 20
Is arranged so as to be drivable in the main body of the device (not shown), and the blade
On the side of 20, cutting water supply pipe that supplies cutting water at the time of cutting
11 and 13 are arranged in the cutting head 15. Blade 20
A work table (wafer mounting table) 18 is mounted on the base of the dicing device below the X direction by a moving mechanism (not shown) in the X direction,
It is arranged so as to be movable in the Y parallel and θ directions.

A wafer 16 (brittle material) is adsorbed and placed on the work table 18, and the wafer 16 is cut into chips by moving the work table 18 along a cut line on the wafer during cutting. At the time of cutting, as shown in FIG. 2, cutting water nozzles 11A, 11A provided on the cutting water supply pipes 11, 13 ...
…, Cutting water from 13A dicing blade 20 and wafer 1
The blade 20 and the wafer 16 are jetted toward 6 to be cut while being washed.

FIG. 3 is an explanatory view of the dicing method according to the present invention, and shows a processing locus when the wafer is downcut.
In FIG. 3, first, the cutting line 22A shown by the solid line while supplying the cutting water and the cleaning water as in the conventional case.
The wafer 16 is cut along. At this time, the wafer 16 is moved via the work table 18 and cut along the cut line 22A in FIG. And the cut line 2
After cutting 2A, as shown by broken line 24A, work table 1
While indexing 8 in the Y direction, it moves to the start position of the cut line 22B, supplies cutting water from the cutting water nozzles 11A, 11A, ..., 13A to the blade 20 and the wafer 16 and Cut line 22
Cut B. Furthermore, when the cutting line 22B is cut, the cleaning on the cutting line 22B is performed, and the cutting line 22A is also cleaned.
The top is also cleaned at the same time, and the dirt that cannot be completely removed at the time of cutting is cleaned.

And cut line 22C by cut line check etc.
When the cutting is temporarily stopped at 1, the wafer 16 is reciprocated once in the X direction while maintaining the Y coordinate before the wafer is dried. That is, the cutting water is supplied to the cutting water nozzle 11 while reciprocating once while the blade 20 is released from the wafer surface along the cut line 22C that is cut immediately before the blade 20 is stopped in the X direction.
Supply from A, 11A ..., 13A and cut line 22C again.
Is washed. This operation is controlled by a control unit (not shown) built in the dicing machine in advance.

As described above, since the line immediately after cutting is cleaned again, it is possible to surely remove the dirt from each line after cutting, and it is possible to wash away all the dirt on the wafer. As a result, the cleanliness of the processed chip can be dramatically improved. Further, from the horizontal cut to the vertical cut, even when changing the cutting direction, the dicing blade 20 or the wafer 16 is controlled to reciprocate once along the line cut immediately before the end of cutting, and again,
By cleaning the lines, the stains on each line can be reliably removed.

〔The invention's effect〕

As described above, according to the dicing method according to the present invention, only when the cutting is completed or when the cutting is paused, the dicing blade is reciprocated once along the line cut immediately before the completion of the cutting or immediately before the pause of the line. I try to wash the top again. For this reason, it is possible to completely remove dirt such as cutting chips attached to each cutting line of the wafer and its periphery at the time of cutting, and it is possible to realize high throughput. Thereby, production of defective chips can be prevented in advance.

[Brief description of the drawings]

1 is an explanatory view showing the positional relationship between a blade and a wafer, FIG. 2 is a plan view of the periphery of a dicing blade, FIG. 3 is an explanatory view of a dicing method according to the present invention, and FIG. 4 is a conventional downcut. It is explanatory drawing which showed the processing locus at the time of performing the dicing processing by. 11A, 13A …… Cutting water nozzle, 15 …… Cutting head, 16 ……
Wafer, 18 ... Work table (wafer mounting table), 20 ...
… Dicing blades, 22A, 22B… Cut lines.

Claims (1)

(57) [Claims] 1. A dicing blade is rotatably provided on a cutting head, and a nozzle is provided on the cutting head. The dicing blade and the wafer are washed with cutting water ejected from the nozzle to predetermined a wafer with the dicing blade. In a dicing machine that cuts into chips along a cut line, after cutting a wafer along one cut line, the dicing blade is obliquely returned while indexing and feeding a wafer mounting table or a cutting head by a predetermined amount. Move to the cutting start position of the next cut line so that it becomes a feed and cut a plurality of the next cut lines, immediately after the cutting of the last cut line in the same direction is finished or immediately after the wafer cutting along any cut line is paused. Only, the line of the wafer cut just before the end of cutting or just before the pause , Said the line on while moving the wafer table or cutting head as dicing blade along again by cutting water, dicing wherein the washing.