JPH08124882A - Dicing method - Google Patents

Abstract

PURPOSE: To prevent erroneous alignment even if the same kind of wafer having a different size is mixed in the same cassette by a method wherein there is provided a step confirming whether a wafer size registered in CPU coincides with a real wafer size. CONSTITUTION: A wafer W is positioned just under alignment means 7 by transferring a chuck table. After the alignment, it is transferred to a cutting region 8 and performed dicing by a rotation blade 9. When performing dicing by this rotation blade 9, there is provided a step for beforehand registering a diameter of the wafer W to be performed dicing in CPU. Thus, an optimum cutting stroke is computed based on coordinates of a position to be appropriately performed an alignment and cutting, and the cutting is performed without useless movements to enhance producibility.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dicing method for dicing a semiconductor wafer or the like.

[0002]

2. Description of the Related Art Generally, when a semiconductor wafer is diced by a dicer, wafers of the same kind and size are accommodated in a cassette, and the wafers are pulled out from the cassette one by one for alignment, and then diced. In order to efficiently perform this alignment and dicing, the diameter of the wafer to be diced is C
Registered in PU.

[0003]

However, when the wafer diameter is erroneously registered, the cutting stroke in dicing becomes insufficient or excessive, which causes a decrease in productivity. There is.
That is, if the wafer diameter to be diced is 6 inches and the wafer diameter is mistakenly registered as 5 inches in the CPU, the calculated cutting stroke becomes insufficient, and in the opposite case, it becomes excessive. . In rare cases, if wafers with the same type of circuit pattern but different diameters are mixed in the same cassette, dicing may be performed without noticing it, or the wafer does not exist at a predetermined position and alignment is performed. There is also the problem that errors will occur. The present invention has been made in order to solve such a conventional problem. Even if wafer diameters are erroneously registered or wafers of the same kind and different sizes are mixed in the same cassette, erroneous alignment and dicing are performed. An object of the present invention is to provide a dicing method that prevents the above.

[0004]

As means for technically solving the above problems, a step of registering a wafer size to be diced in a CPU, and a step of transferring a wafer to be diced to a chuck table or after the wafer is transferred. And a dicing method including at least a step of confirming whether or not the wafer has a dicing planned wafer size registered in the CPU, and a step of displaying an error if the wafer is not the dicing planned wafer size. To do. Also, the size of the wafer to be diced is detected by pattern matching, and it is confirmed whether or not the wafer is the size of the wafer to be diced. The shape recognition is used to detect the size of the wafer to be diced, and the wafer is diced. Confirm whether it is the planned wafer size, detect the wafer size of the wafer to be diced by non-contact type object recognition means such as laser light or ultrasonic waves, and check if the wafer is the planned wafer size To confirm whether or not, by a contact type object recognition means such as a stylus, to detect the size of the wafer to be diced, and confirm whether or not the wafer is the size of the wafer to be diced Is the gist. Further, a step of registering a wafer size to be dicing into the CPU, and a step of transferring the wafer to be diced to or after being transferred to the chuck table, and determining whether or not the wafer is the wafer size to be diced in the CPU. The gist of the dicing method is to include at least a step of confirming whether the wafer size is a planned dicing wafer size and a step of measuring the wafer size and re-registering it in the CPU.

[0005]

[Operation] Since there is a step to confirm whether the wafer size registered in the CPU matches the actual wafer size, the wafer diameter may be registered incorrectly, or the same size and different size may be stored in the same cassette. Even if the above wafers are mixed, the alignment will not be disabled, and the cutting stroke in dicing will not be insufficient or excessive.

[0006]

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 shows an example of a dicer, in which a cassette 2 containing a semiconductor wafer W (attached to a frame F via an adhesive tape T) is placed in a wafer placement area 1 having a vertically movable table.

The wafer W in the cassette 2 is unloaded to the standby area 4 by the loading / unloading means 3 and is also transferred onto the chuck table 6 by the transfer means 5 having a swing arm.

The wafer W sucked and held on the chuck table 6 is positioned directly below the alignment means 7 by the movement of the chuck table, aligned, moved to the cutting region 8, and diced by the rotary blade 9.

When performing the dicing by the rotary blade 9, if the step of registering the diameter of the wafer W to be diced in the CPU (not shown) is provided in advance as shown in FIG. 2, proper alignment and cutting should be performed. The optimum cutting stroke, for example, the distance from x ₁ to x ₂ , the distance from x ₃ to x _4, etc., can be calculated based on the position coordinates, and cutting can be performed without unnecessary movement to improve productivity. .

Therefore, in dicing, the wafer W is
Since the diameter of is also important information, it is registered in the CPU prior to dicing as described above. As a means for recognizing the size of the wafer W, for example, a CCD camera is provided above the chuck table 6 or above the standby region 4 as shown by a virtual line in FIG. Shape recognition means 10A or 10B for recognizing the difference in contrast and recognizing the shape of the wafer W
To provide.

Such shape recognition means 10A or 10B
Holds the wafer W to be diced on the chuck table 6
When or after the wafer is transferred to, the step of confirming whether or not the wafer W has a wafer size for dicing is performed, and when the wafer W has a wafer size for dicing, proceed to a cutting step, If the wafer size is not the dicing planned wafer size, a step of displaying an error is performed. Further, the size of the wafer W may be measured and re-registered in the CPU in the step of displaying the error and, in place of it, confirming whether or not the wafer size is the dicing planned wafer size.

In the case of the error display, alignment and dicing are not performed, and therefore, erroneous alignment and dicing can be prevented. After the correction, proper alignment and dicing are performed. When the wafer size is re-registered in the CPU, dicing is performed based on the new wafer size, and the size of the next wafer W is confirmed.

As a means for recognizing the size of the wafer W, a non-contact type object recognizing means for recognizing the contour of the wafer W by detecting the step between the wafer W and the adhesive tape T by laser light or ultrasonic waves is provided. Alternatively, the size of the wafer W may be detected by a contact-type object recognition unit such as a stylus type.

Further, the diameter of the wafer W may be recognized by pattern matching using the alignment means 7 without providing any special recognition means as described above. That is, based on the wafer diameter registered in the CPU, it is detected whether or not a pattern exists near the maximum value of the diameter, and if the pattern does not exist, an error is displayed as a small diameter, and if it exists, Further, it is detected whether or not a pattern exists on the outer side, and if it exists, an error is displayed as a large diameter. In addition, as an error display, a sound,
Light, display, etc.

[0015]

As described above, according to the present invention,
Since a step for confirming whether the wafer diameter registered in the CPU in advance matches the actual wafer diameter to be diced is provided, the wafer diameter is erroneously registered, or the same diameter is different in the same cassette. Even if a wafer of a size is mixed, it is possible to prevent the alignment from being disabled or the cutting stroke in dicing being insufficient or excessive.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of a dicer to which the method of the present invention is applied.

FIG. 2 is an explanatory diagram showing a cutting portion of a wafer.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Wafer mounting area 2 ... Cassette 3 ... Carrying in / out means 4 ... Standby area 5 ... Conveying means 6 ... Chuck table 7 ... Alignment means 8 ... Cutting area 9 ... Rotating blade
10A, 10B ... Shape recognition means

Claims (6)

[Claims] 1. The wafer size to be diced is CP
A step of registering with U, a step of confirming whether or not the wafer has a wafer size to be diced, which is to be diced when the wafer to be diced is or after being conveyed to the chuck table, Displaying an error if the wafer size is not the expected wafer size. 2. The dicing method according to claim 1, wherein the size of the wafer to be diced is detected by pattern matching, and it is confirmed whether or not the wafer has the size to be diced. 3. The dicing method according to claim 1, wherein the size of the wafer to be diced is detected by shape recognition, and it is confirmed whether or not the wafer is the size of the wafer to be diced. 4. A wafer size of a wafer to be diced is detected by a non-contact type object recognition means such as a laser beam or an ultrasonic wave, and it is confirmed whether or not the wafer has a size to be diced. The dicing method described. 5. The dicing according to claim 1, wherein the contact type object recognizing means such as a stylus type detects the size of the wafer to be diced and confirms whether or not the wafer is the size of the wafer to be diced. Method. 6. The wafer size for dicing is CP
A step of registering with U, a step of confirming whether or not the wafer has a wafer size to be diced, which is to be diced when the wafer to be diced is or after being conveyed to the chuck table, If the wafer size is not the expected wafer size, the wafer size is measured and re-registered in the CPU.