JPH06310596A - Dicing apparatus - Google Patents

Abstract

PURPOSE:To position the place of cutting easily without requiring a dummy wafer exclusive for measurement. CONSTITUTION:A distance D2 from the front end of an optical type displacement sensor 14 to a blade 11 is measured by the sensor 14, and input to an NC device 16 through an A/D converter 15. A distance D1 from the reference line 18 of a microscope 13 to the front end of the optical type displacement sensor 14 is stored previously in the NC device 16, and a distance D between the blade 11 and the reference line 18 of the microscope 13 is obtained as D=D2-D1. The NC device 16 controls the position of cutting of a wafer by the blade 11 on the basis of the distance D.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art In a dicing apparatus for cutting a semiconductor wafer, an operator determines a cutting position while observing the wafer with a microscope. However, the cutting tool (hereinafter, referred to as a blade) changes its position due to displacement or exchange due to heat during rotation, so that the relative distance between the microscope and the blade is not constant. Therefore, it is necessary to measure the relative distance between the microscope and the blade in advance in order to position the cutting position.

Conventionally, the relative distance between the microscope and the blade has been measured as follows. That is, a wafer different from the product called a dummy wafer is prepared, and first, the reference line provided on the microscope, for example, the reference line of the microscope is aligned with the position to be cut on the dummy wafer,
Perform trial cutting.

Next, while looking at the microscope, the table is moved to align the cutting trace of the trial cutting with the reference line of the microscope. Then, the moving distance of the table at that time is measured and used as the relative distance between the microscope and the blade.

[0005]

However, such a conventional method has the following two problems. The first problem is that a wafer for measurement, called a dummy wafer, is always required.

The second problem is that in order to measure the relative distance between the microscope and the blade, dummy wafer supply, trial cutting,
The point is that a series of operations such as measuring the relative distance between the microscope and the blade and discharging the dummy wafer are required. In order to perform this operation, each machine step must be emptied, and when another wafer is in each machine step,
Further, an operation of discharging this wafer is required, and an extra operation and time are required.

Therefore, an object of the present invention is to provide a dicing apparatus which can easily position a cutting position without requiring a dummy wafer dedicated to measurement.

[0008]

A dicing apparatus according to the present invention comprises a cutting tool for cutting a semiconductor wafer, a microscope for confirming a cutting position of the semiconductor wafer, and a predetermined positional relationship with respect to the microscope. Based on the distance between the measuring means and the measuring means arranged in a non-contact manner to measure the distance to the cutting tool, and the distance measured by the measuring means, cutting for controlling the cutting position by the cutting tool. And position control means.

[0009]

In this dicing device, the measuring means
The distance between the measuring means and the cutting tool is measured, and based on the measured distance and the distance between the measuring means and the microscope which are known in advance, the cutting position by the cutting position control means is cut by the cutting tool. Controlled.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the dicing apparatus of the present invention will be described in detail below with reference to the drawings. FIG. 1 is an explanatory diagram showing a schematic configuration of a dicing apparatus according to the first embodiment of the present invention. This dicing device includes a blade 11 for cutting a semiconductor wafer (not shown), a spindle motor 12 for rotating the blade 11, a microscope 13 for confirming a cutting position of the semiconductor wafer, and a microscope 13 for the microscope 13 in advance. An optical displacement sensor 14 such as a laser displacement sensor, which is arranged at a position determined by machine dimensions and measures the distance to the blade 11 in a non-contact manner, is provided.

The dicing device also includes an analog-digital converter (hereinafter referred to as an A / D converter) 15 for converting the analog output signal of the optical displacement sensor 14 into digital data, and the A / D converter. A numerical controller (hereinafter referred to as an NC device) 16 for inputting output data of the converter 15 and a table drive device 17 controlled by the NC device 16 for moving a table on which a semiconductor wafer is mounted are provided. There is.

A reference line 18 appears in the visual field of the microscope 13. The distance D ₁ between the reference line 18 and the tip of the optical displacement sensor 14 is known in advance. Further, the optical displacement sensor 14 is arranged at a position facing the blade 11, measures the distance D ₂ from the tip of the optical displacement sensor 14 to the blade 11, and outputs an analog voltage corresponding to the distance D ₂ , for example. . In addition to the table driving device 17, the NC device 16 numerically controls the entire dicing device such as the spindle motor 12 and the like.

Next, the operation of this embodiment will be described.
In the present embodiment, for example, when the distance D between the blade 11 and the reference line 18 of the microscope 13 is obtained after the blade replacement, etc., the distance D ₂ from the tip to the blade 11 is determined by the optical displacement sensor 14. taking measurement. The information on the distance D ₂ is input to the NC device 16 via the A / D converter 15.

The NC device 16 includes a reference line 18 of the microscope 13.
And prestores the distance D ₁ of the to the tip of the optical displacement sensor 14, from the distances D _2, D _1, the blade 1
1 is the distance D between the reference line 18 of the microscope 13 and D = D
_2- D ₁ is calculated. Since the blade 11 is displaced by heat due to rotation, when the distance D ₂ from the tip of the blade 11 to the blade 11 is measured by the optical displacement sensor 14, it is reliable that the blade 11 is rotated. Is desirable.

After this measurement, the semiconductor wafer is cut as follows. First, an operator specifies a cutting position while observing a semiconductor wafer with the microscope 13. This designation is performed, for example, by matching the reference line 18 of the microscope 13 with the cutting position of the semiconductor wafer.

Here, the blade 11 is measured by the above-mentioned measurement.
Since the distance D between the reference line 18 of the microscope 13 and the reference line 18 of the microscope 13 is obtained, the NC device 16 moves the table from the state in which the operator sets the reference line 18 of the microscope 13 to the position where the semiconductor wafer is cut. It is moved by a distance D and cut. As a result, the semiconductor wafer is accurately cut at the desired position. The other cutting on the same wafer is performed by sequentially moving the table by a predetermined distance according to the size of the chip.

Thus, according to this embodiment, the blade 1
To measure the distance between 1 and the reference line 18 of the microscope 13, a dummy wafer dedicated to measurement is not necessary. Further, since the operation of cutting the dummy wafer is not necessary, the operation and time for measurement are greatly shortened, and the measurement can be performed regardless of the situation of each process of the machine, and the productivity of the machine is improved.

FIG. 2 is an explanatory diagram showing a schematic structure of a dicing apparatus according to the second embodiment of the present invention. In the second embodiment, the distance between the center of the blade 11 and the reference line 18 of the microscope 13 can be measured in consideration of the thickness of the blade 11. That is, in this embodiment, the two optical displacement sensors 21 and 22 are provided at positions facing each other with the blade 11 interposed therebetween.

The sensors 21 and 22 are separated from each other by a distance D ₂ from the tip of the sensor to the surface of the opposite blade 11.
Measure D ₃ . The information on the distances D ₂ and D ₃ is input to the NC device 16 via the A / D converter 15 as in the first embodiment. The NC device 16 stores in advance the distances D ₁ and D ₄ from the reference line 18 of the microscope 13 to the tips of the respective sensors 21 and 22, and from these distances D ₁ , D ₂ , D ₃ and D ₄ , The distance D between the center of the blade 11 and the reference line 18 of the microscope 13 is D = D ₂ −D ₁ + (D ₄ + D ₁ −D ₃ −
D ₂ ) / 2 = (D ₄ −D ₃ + D ₂ −D ₁ ) / 2.

Other configurations, operations and effects are similar to those of the first embodiment. The present invention is not limited to the above-mentioned embodiments, for example, the measuring means for measuring the distance to the cutting tool,
Not limited to the optical sensor, any microwave sensor, ultrasonic sensor, or the like that can measure the distance in a non-contact manner may be used.

[0021]

As described above, according to the present invention, there is provided a measuring means which is arranged in a predetermined positional relationship with respect to the microscope and which measures the distance to the cutting tool in a non-contact manner. Measures the distance between the blade and the measured distance, and based on the distance between the measuring means and the microscope known in advance, the cutting position by the blade is controlled. It is possible to easily position the cutting position without the need for the dummy wafer.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a schematic configuration of a dicing apparatus according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a schematic configuration of a dicing apparatus according to a second embodiment of the present invention.

[Explanation of symbols]

 11 Blade 13 Microscope 14 Optical Sensor 15 A / D Converter 16 NC Device 17 Table Drive Device 18 Microscope Reference Line

Claims (1)

[Claims] 1. A cutting tool for cutting a semiconductor wafer, a microscope for confirming a cutting position of a semiconductor wafer, and a microscope arranged to have a predetermined positional relationship with respect to the microscope. And a cutting position control means for controlling a cutting position by the cutting tool based on a distance between the measuring means and the microscope and a distance measured by the measuring means. A dicing device characterized by.