JPH03181148A - Dicing method - Google Patents

Abstract

PURPOSE:To securely remove contaminants such as cut chips and prevent a defective chip from being produced by reciprocating a dicing blade along a line which is just cut and cleaning again the line at the time of completion or temporary suspension of cutting. CONSTITUTION:At the time of cutting a wafer 16 sucked and mounted on a work table 18, cutting water is jetted from cutting water nozzles 11A, 11A, 13A provided on cutting water supply tubes 11, 13 toward a dicing blade 20 and the wafer 16 to cut the wafer 16 while the blade 20 and the wafer 16 are cleaned. At the time of completion of cutting or temporary suspension, the wafer mount table 18 or a cutting head 15 is moved with the blade 20 along a line which has been just cut, and at the time of moving, cut chips or other contaminants attached to a groove on the line and its vicinity are again cleaned off and removed by the cutting water. Thus cleanliness of the wafer 16 after cutting is improved thereby preventing production of defective chips.

Description

DETAILED DESCRIPTION OF THE INVENTION [Second Industrial Fields] The present invention relates to a dicing method, and particularly to a dicing method for cutting brittle materials such as semiconductor wafers.

[Conventional technology]

Conventionally, dicing equipment that cuts silicon wafers into semiconductor chips rotates the dicing blade at high speed to cut the wafer, but during cutting, the blade is exposed to cutting water and the wafer is washed with cleaning water while cutting. Implement. Cutting water reduces cutting resistance, cleans the blade, and removes dirt caused by chips during cutting. Further, the cleaning water directly cleans the wafer, removes dirt such as attached chips, and maintains the cleanliness of the wafer.

Dicing can be roughly divided into two types: up-cut and down-cut, and FIG. 4 is an explanatory diagram showing the machining trajectory when dicing is performed by down-cut using a movable cutting head. In FIG. 4, first, the wafer 10 is cut along a processing line 12A shown by a solid line from left to right while supplying cutting water and cleaning water. After cutting on the processing line 12A, while supplying cutting water and cleaning water, the wafer is indexed by a predetermined amount in the Y direction as shown by the broken line 14A to perform cutting on the next processing line 12B. Cutting name of -
Then, in step 5), the wafer 10 is cut along the processing line 12B. At this time, cut fin 12
The cutting water supplied when cutting B simultaneously cleans the groove of the previously cut cut line 12A and the dirt around it.

Cutting is performed by repeating such operations.

[Problem to be solved by the invention]

However, in the conventional dicing method, the line where the last cut was made is cleaned only once during cutting, so it is difficult to completely remove dirt such as powder chips that adhere to the cut groove and its surroundings. There is a drawback that it cannot be done.

Also, during the dicing process, the width of the cutting groove, the amount of chipping,
In the cut line check, which automatically measures and displays center deviation using a microscope or the like, cutting is temporarily stopped, the upper surface of the wafer is dried by air blowing, and then the wafer is observed.

For this reason, the line cut immediately before the temporary stop is cleaned only once at the time of cutting, resulting in insufficient removal of dirt. If a wafer is dried with dirt such as chips attached, the chips will solidify and become impossible to remove no matter how much cleaning is performed.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a dicing method that can reliably remove dirt such as chips that adhere to the cut line of a wafer and its surroundings during cutting. With the goal.

[Means to solve the problem]

In order to achieve the above object, the present invention includes a cutting head rotatably provided with a dicing blade, a nozzle provided in the cutting head, and cleaning the dicing blade and wafer with cutting water jetted from the nozzle. In a dicing machine that cuts a wafer into chips along predetermined cut lines with a dicing blade, immediately after cutting is finished or paused, the dicing blade follows the line of the wafer that was cut just before finishing cutting or just before stopping. While moving the wafer mounting table or the cutting head, the cutting water is again applied to the line.
It is characterized by cleaning.

[Condolence]

According to the present invention, at the end of cutting in a predetermined direction or at a pause during cutting, the wafer mounting table or the cutting head is moved so that the dicing blade follows the line cut just before the end of cutting or just before the pause. When moving, the cutting water is again used to wash and remove dirt such as chips adhering to the grooves on the line and their surroundings. Thereby, the cleanliness of the wafer after cutting can be improved.

Second Embodiment: Hereinafter, preferred embodiments of the 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 Figure 1, the dicing blade 2
Cutting water supply pipes 11 and 13 for supplying cutting water during cutting are installed in the cutting head 15 on the sides of the blade 20.

A work table (wafer mounting table) 18 is disposed on the base of the dicing device below the blade 20 and is movable in the X direction, Y direction, and θ direction by a moving mechanism (not shown).

A wafer 16 (brittle material) is placed on the work table 18 by suction, and when cutting, the wafer 16 is moved by moving the work table 18 along the cut line on the wafer.
Cut into chips.

During cutting, the cutting water supply pipe 11.1 is
Cutting water nozzle IIAS 11A installed in 3...
Cutting water is jetted from 13A toward the dicing blade 10 and the wafer 16 to clean the blade 10 and the wafer 16 while cutting.

FIG. 3 is an explanatory diagram of the dicing method according to the present invention, and shows a processing locus when a wafer is down-cut. In FIG. 3, first, while supplying cutting water and cleaning water as in the conventional case, the cut line 22A shown by the solid line is cut.
Cut the wafer 16 along. 2, wafer 1
6 is moved through the work table 18 and cut along the cut line 22A in FIG. After cutting the cant line 22A'', the supply of cutting water is stopped, and the work table 18 is indexed by a predetermined amount in the Y direction as shown by the broken line 24A, and moved to the start position of the cut line 22B. Then, cutting water is supplied from the cutting water nozzles IIA, 11A, . . . , 13A to the blade 20 and the wafer 16, and the blade 20 cuts the cut line 22B. Furthermore, cut line 22
When cutting B, in addition to cleaning on the cut line 22B, the top of the cut line 22A is also cleaned at the same time to clean dirt that could not be removed during cutting.

Then, check cut line 22C etc.
When cutting is temporarily stopped, the wafer 16 is reciprocated once in the X direction while maintaining the Y coordinate before drying the wafer. That is, the blade 20 is cut from the wafer surface along the cut line 22C cut immediately before the blade 20 is temporarily stopped in the X direction.
Cutting water is supplied from the cutting water nozzles 11A, IIA, . . . 13A, and the cutting line 22C is cleaned again. This operation is controlled by a control section (not shown) that is pre-installed in the dingmann.

In this way, since the line immediately after cutting is washed again, dirt can be reliably removed from each line after cutting, and it is possible to wash away all dirt on the wafer. Thereby, the cleanliness of the chip after processing can be dramatically improved. Also, when changing the cutting direction from jet cutting to vertical cutting, the dicing blade 20 or wafer 16 is controlled to reciprocate once along the cut line just before the cutting is finished, and the cleaning on the line is performed again. By doing this, you can reliably remove dirt on each line.

In this embodiment, the case where down cutting is performed has been described, but of course it is also possible to apply to die song processing where up cutting or up/down cutting is performed.

Furthermore, if the distance between the cut lines is wide, it is recommended that cutting water be supplied over the already cut cut line every time one cut line is cut, and the cut line must be made to reciprocate once to perform washing and cleaning again. Moyo',).

[Effects of the Invention As explained above, according to the dicing method of the present invention, at the end of cutting or at a pause during cutting, the dicing blade is moved along the line cut immediately before the end of cutting or immediately before the pause. The line is cleaned again by going back and forth. For this reason, it is possible to remove all dirt such as chips adhering to each cut line of the wafer and its surroundings during cutting. This makes it possible to prevent the production of defective chips.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram showing the positional relationship between the blade and the wafer, Fig. 2 is a plan view of the vicinity of the dicing blade, Fig. 3 is an explanatory diagram of the dicing method according to the present invention, and Fig. 4 is a conventional down cut. FIG. 2 is an explanatory diagram showing a machining locus when die song machining is performed. 11AS 13A... Cutting water nozzle, 15...
Cutting head, 16... Wafer 18... Work table (wafer mounting stand), -20... Dicing blade, 22A, 22B... Cut line.

Claims (1)

[Scope of Claims] A dicing blade is rotatably provided on the cutting head, and a nozzle is provided on the cutting head, and the wafer is placed in a predetermined position with the dicing blade while cleaning the dicing blade and the wafer with cutting water jetted from the nozzle. In a dicing machine that cuts chips into chips along a cut line, immediately after cutting is finished or paused, the dicing blade is placed on a wafer mounting table or on the line of the wafer that was cut just before finishing cutting or just before stopping. A dicing method characterized by cleaning the line again with cutting water while moving the cutting head.