JPH06106524A - Slicing method for semiconductor wafer - Google Patents

Abstract

PURPOSE:To cut a wafer into a required shape by a method wherein when cutting is conducted with the correction of a displacement of a cutting blade mounted on a rotating spindle by an air pad, a spindle rotating speed and/or a cutting feed speed is controlled by at least one of a cutting load resistance change, a cutting part peripheral length change, and an air pad pressure change. CONSTITUTION:A displacement of a blade 14 is detected by a blade sensor 32 and corrected by an air pad 30. A controller 26 controls a rotating speed of a spindle 10, a cutting feed mechanism 22 for an ingot 18, and a pressure adjusting device 36 for the air pad 30. Data of at least one of a cutting load resistance change, a cutting part peripheral length change, and a pressure change of the air pad 30 is used as a parameter. With the increase of the value, the rotating speed of the spindle 10 is raised and a cutting feed speed is lowered. On the other hand, with the decrease of the value, the rotating speed of the spindle 10 is lowered and a cutting feed speed is raised for reducing the warpage of the cutting blade 14. Both or either of the rotating speed and the feed speed can be controlled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor wafer slicing method, and more particularly to a semiconductor wafer slicing method capable of processing a wafer having a desired shape.

[0002]

2. Description of the Related Art The cutting edge portion of an inner peripheral blade or an outer peripheral blade of a slicing machine is composed of diamond abrasive grains. These cutting edges wear unevenly with use, and this uneven wear draws a cutting curve in either direction. For example, if the cutting blade is worn in a shape that warps upward, as the cutting progresses and the cutting load resistance increases, the warping shape of the wafer also gradually increases upward, and the cutting load resistance becomes maximum at the maximum cutting length. The warp displacement of is also maximum. As the cutting progresses further, the cutting length gradually decreases, the cutting load resistance decreases, and the warp displacement gradually decreases.

[0003]

However, the above slicing method has a problem that a wafer having an upper or lower warp shape is processed. Conventionally, wafer warpage control has been implemented in order to eliminate such a problem. That is, the sensor detects the displacement of the blade, and the air pad is operated so that the displacement of the blade at the position of the sensor becomes zero, thereby controlling the warpage. As another conventional warpage control, the air pad is operated so that the displacement of the central portion of the cutting position of the semiconductor material becomes zero, and the semiconductor material is cut.

However, the conventional slicing method is
Since the air pad is controlled so that the blade displacement at the sensor position or the center position becomes zero, there is a drawback that it becomes a cylindrical wafer or a square wafer as shown in FIG. Such a cylindrical wafer and a paddle wafer are disadvantageous for post-processing of the wafer. The present invention has been made in view of such circumstances, and an object of the present invention is to propose a slicing method of a semiconductor wafer capable of processing a wafer having a desired shape.

[0005]

In order to achieve the above object, the present invention is to attach a cutting blade to a rotating spindle, press a semiconductor material against the cutting blade, and bring the cutting blade or the semiconductor material relatively close to each other. A method of slicing a semiconductor wafer, which is moved to cut a semiconductor material into thin flakes, in which the axial displacement of a cutting blade is detected by a sensor and the displacement is corrected by an air pad while cutting. In addition, the rotational speed of the spindle is controlled and the displacement of the cutting blade is controlled using at least one data of the change of cutting load resistance, the change of cutting portion circumference, and the change of pressure of the air pad as a parameter to cut a wafer having a desired shape. Is characterized by.

Further, in order to achieve the above object, the present invention provides:
A slicing method of a semiconductor wafer, in which a cutting blade is attached to a rotating spindle, a semiconductor material is pressed against the cutting blade, and the cutting blade or the semiconductor material is moved relatively closer to cut the semiconductor material into flakes. In a slicing method of a semiconductor wafer in which the axial displacement of a blade is detected by a sensor and the displacement is corrected by an air pad, at least one of a cutting load resistance change, a cutting portion peripheral length change, and an air pad pressure change is It is characterized in that the cutting feed speed is controlled by using the data as a parameter to control the displacement of the cutting blade to cut a wafer having a desired shape.

Further, in order to achieve the above object, the present invention provides:
A slicing method of a semiconductor wafer, in which a cutting blade is attached to a rotating spindle, a semiconductor material is pressed against the cutting blade, and the cutting blade or the semiconductor material is moved relatively closer to cut the semiconductor material into flakes. In a slicing method of a semiconductor wafer in which the axial displacement of a blade is detected by a sensor and the displacement is corrected by an air pad, at least one of a cutting load resistance change, a cutting portion peripheral length change, and an air pad pressure change is The data is used as a parameter to control the rotational speed of the spindle and the cutting feed speed to control the displacement of the cutting blade to cut a wafer having a desired shape.

[0008]

In the method of slicing a semiconductor wafer according to the present invention, the rotational speed of the spindle and / or the cutting feed speed are controlled by using at least one data of cutting load resistance, cutting part peripheral length change, and air pad pressure change as parameters. It is characterized in that the wafer is cut by controlling the displacement of the cutting blade.

That is, in the present invention, when the cutting load resistance becomes large, it is judged that the sharpness of the cutting blade is deteriorated, and the spindle rotational speed is increased. This reduces the warp shape of the blade. Further, in the present invention, the spindle rotation speed is increased when the cutting portion peripheral length is increased, and is decreased when the cutting portion peripheral length is decreased such as at the beginning of cutting or immediately after the end of cutting. Further, in the present invention, when the air pressure of the air pad increases, the spindle rotation speed increases, and when the air pressure of the air pad decreases, the spindle rotation speed decreases. The number of revolutions of the spindle is controlled by using at least one of data of change in cutting load resistance, change in circumference of cutting portion, and change in pressure of air pad.

In the present invention, when the cutting load resistance becomes large, it is judged that the cutting blade has deteriorated sharpness, and the cutting feed speed is reduced. This reduces the warp shape of the blade. Further, in the present invention, the cutting feed speed is reduced when the cutting portion circumference is increased, and is increased when the cutting portion circumference length is decreased such as at the beginning of cutting or just before the end of cutting. Further, in the present invention, the cutting feed speed is decreased when the air pressure of the air pad is increased, and the cutting feed speed is increased when the air pressure of the air pad is decreased. The cutting feed speed number is controlled by using at least one of data of cutting load resistance change, cutting part peripheral length change, and air pad pressure change data.

In the present invention, the cutting may be performed by controlling either the spindle rotation speed or the cutting feed speed, or by controlling both the spindle rotation speed and the cutting feed speed.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a semiconductor wafer slicing method according to the present invention will be described in detail below with reference to the accompanying drawings. In FIG. 1, a chuck body 12 is fixed to the upper end of the spindle 10, and the spindle 10
A motor 13 is connected to the lower end of the spindle 13, so that the spindle 10 and the chuck body 12 can rotate.

An outer peripheral edge of a doughnut-shaped blade 14 is pulled up on the chuck body 12, and an inner peripheral blade 16 is formed on the inner peripheral edge of the blade 14. The inner peripheral blade 16 is composed of fine diamond abrasive grains or the like. Also,
The outer peripheral edge of the blade 14 can be adjusted in tension by a known tensioning mechanism (not shown) of the chuck body 12. The controller 26 uses the motor 13
The speed of the spindle 12 is controlled via the.

The upper end of the semiconductor ingot 18 is fixed to the work support base 21. Further, the ingot 18 can be moved in the cutting feed direction (XX direction) by the cutting feed mechanism 22, and the work support base 21 is further moved by the work indexing mechanism 24 (Z-Z direction).
Direction). The cutting feed mechanism 22 and the work indexing mechanism 24 are driven by a command signal from a control device 26. The control device 26 controls the cutting and feeding mechanism 22 via a motor (not shown).
Controls the cutting feed speed of.

Further, as shown in FIGS. 1 and 2, a pair of non-contact type air pads 30 are provided on the upper surface of the blade 14.
30, blade sensors 32, 32 are arranged. The blade sensors 32, 32 detect the displacement of the blade 14, and the air pads 30, 30 detect the blade 14
The displacement of can be corrected. Further, the blade sensors 32, 32 are connected to the control device 26,
Controls the air pressure adjusting device 36 to operate the air pads 20, 20.

The wafer slicing machine of the present invention is carried out as follows by the slicing machine configured as described above. First, the ingot 18 is moved toward the inner peripheral blade 16 in the X direction to start cutting. Generally, the relationship between cutting load resistance, cutting section circumference, and ingot cutting feed speed is that the cutting resistance increases as the cutting section circumference increases,
The cutting resistance increases as the ingot cutting feed speed increases. Also, when the cutting load resistance increases,
As a matter of course, the displacement of the blade 14 becomes large, and the blade 14 easily warps.

In the semiconductor wafer slicing method according to the present invention, the spindle rotation speed and / or the cutting feed speed are controlled by using at least one data of cutting load resistance, cutting portion peripheral length change, and air pad pressure change as parameters. Disconnect. That is, in the present invention, when the cutting load resistance increases, it is determined that the sharpness of the cutting blade 16 has deteriorated, and the spindle speed is increased. This reduces the warped shape of the blade 14. Further, in the present invention, the spindle rotation speed is increased when the cutting portion peripheral length is increased, the warp of the cutting blade 16 is reduced, and the spindle rotation speed is reduced when the cutting portion peripheral length is reduced such as at the beginning of cutting or just before the end of cutting. Further, in the present invention, when the air pressure of the air pad 30 increases, the spindle rotation speed is increased to reduce the warp of the cutting blade 16, and when the air pressure of the air pad 30 decreases, the spindle rotation speed is decreased. The number of revolutions of the spindle is controlled by using at least one of data on a change in cutting load resistance, a change in cutting portion circumference, and a change in pressure of the air pad 30.

In the present invention, when the cutting load resistance increases, it is determined that the cutting quality of the cutting blade 16 has deteriorated, and the cutting feed speed is reduced. This reduces the warped shape of the blade 14. Further, in the present invention, the cutting feed speed is reduced to reduce the warp of the cutting blade 16 when the cutting portion circumference becomes large, and the cutting feed speed is increased when the cutting portion circumference becomes small such as at the beginning of cutting or near the end of cutting. Further, in the present invention, when the air pressure of the air pad 30 increases, the cutting feed speed is decreased to reduce the warp of the cutting blade 16, and when the air pressure of the air pad decreases, the cutting feed speed is increased. The cutting feed speed number is controlled by using at least one of data of cutting load resistance change, cutting part peripheral length change, and air pad pressure change data.

In the present invention, the cutting may be performed by controlling either the spindle rotation speed or the cutting feed speed, or by controlling both the spindle rotation speed and the cutting feed speed. As described above, a wafer having a desired shape, for example, a flat wafer can be processed.

Further, in the present invention, the sensor 32 is the blade 1
When the displacement of 4 is detected, the cutting position at that time, the sensor 32
Of the semiconductor material 1 to be cut based on the relationship between the position of the blade, the position of the air pad 30, and the amount of blade displacement detected by the sensor 32.
It is also possible to calculate the amount of displacement of the cutting edge of the air pad 30 and control the warp so that the displacement of the cutting edge of the semiconductor material to be cut becomes zero.

When the ingot 18 is cut while controlling the warp so that the displacement amount becomes zero at each cutting position, the displacement of the cutting edge of the inner peripheral blade 16 with respect to the ingot 18 becomes zero. The bowl-shaped wafer shown can be processed. Such a bowl-shaped wafer is advantageous in post-processing. In the above embodiment, the pair of sensors 32,
Although the change of the blade 14 is detected by 32 and the warp control is performed based on the change, the invention is not limited to this. That is, an eddy current sensor may be provided at the center of the cutting position to detect the blade position at the center of the cutting position, and the change in the wafer peripheral edge may be calculated from this change amount. Further, the change of the wafer peripheral edge may be calculated by the calculation of the pair of sensors 32, 32 and the central sensor.

[0022]

As described above, according to the semiconductor wafer slicing method of the present invention, at least one of the change in cutting load resistance, the change in circumference of the cutting portion, and the pressure of the air pad.
Since the number of revolutions of the spindle and / or the cutting feed speed are controlled by using one data as a parameter, the wafer having a desired shape can be processed.

[Brief description of drawings]

FIG. 1 is a schematic front view of a slicing machine.

FIG. 2 is a schematic plan view of a slicing machine.

FIG. 3 is an explanatory view of a wafer processed by a conventional slicing method.

FIG. 4 is an explanatory view of a wafer processed by the slicing method of the present invention.

[Explanation of symbols]

 10 ... Spindle 14 ... Blade 16 ... Inner peripheral blade 18 ... Ingot 22 ... Cutting feed mechanism 26 ... Control device 30 ... Air pad 32 ... Sensor

Claims (5)

[Claims] 1. A cutting blade is attached to a rotating spindle,
A semiconductor wafer slicing method in which a semiconductor material is pressed against a cutting blade, and the semiconductor material is cut into thin pieces by moving the cutting blade or the semiconductor material relatively close to each other.A sensor detects axial displacement of the cutting blade. In addition, in the slicing method of a semiconductor wafer in which the displacement is corrected while being corrected by an air pad, the spindle speed A method for slicing a semiconductor wafer, which comprises controlling the wafer to cut the wafer. 2. A cutting blade is attached to a rotating spindle,
A semiconductor wafer slicing method in which a semiconductor material is pressed against a cutting blade, and the semiconductor material is cut into thin pieces by moving the cutting blade or the semiconductor material relatively close to each other, and a sensor detects axial displacement of the cutting blade. In addition, in the slicing method of the semiconductor wafer in which the displacement is corrected by the air pad while cutting, the cutting feed speed is set by using at least one data of the cutting load resistance change, the cutting part circumference change, and the air pad pressure change as parameters. A method of slicing a semiconductor wafer, which comprises controlling and cutting the wafer. 3. A cutting blade is attached to a rotating spindle,
A semiconductor wafer slicing method in which a semiconductor material is pressed against a cutting blade, and the semiconductor material is cut into thin pieces by moving the cutting blade or the semiconductor material relatively close to each other, and a sensor detects axial displacement of the cutting blade. In addition, in the slicing method of a semiconductor wafer in which the displacement is corrected while being corrected by an air pad, the spindle speed And a method for slicing a semiconductor wafer, which comprises cutting a wafer by controlling a cutting feed speed. 4. A cutting blade is attached to a rotating spindle,
A semiconductor wafer slicing method in which a semiconductor material is pressed against a cutting blade, and the semiconductor material is cut into thin pieces by moving the cutting blade or the semiconductor material relatively close to each other, and a sensor detects axial displacement of the cutting blade. In addition, in the slicing method of a semiconductor wafer in which the displacement is corrected while being corrected by an air pad, the spindle speed A method of slicing a semiconductor wafer, characterized in that at least one of the cutting and feeding speed is controlled to cut the wafer into a desired shape. 5. A cutting blade is attached to a rotating spindle,
A semiconductor wafer slicing method in which a semiconductor material is pressed against a cutting blade, and the semiconductor material is cut into thin pieces by moving the cutting blade or the semiconductor material relatively close to each other.A sensor detects axial displacement of the cutting blade. In addition, in the slicing method of a semiconductor wafer in which the displacement is corrected while being corrected by an air pad, the spindle speed A method of slicing a semiconductor wafer, wherein at least one of the cutting and feeding speed is controlled so that the change of the outer peripheral edge of the wafer becomes zero, and the wafer is cut into a bowl shape.