JP2001345252A - Laser cutter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laser cutter which cuts a protective film, a photoresist film, and a base film along the outer periphery of a semiconductor wafer in such a way that the wafer and photoresist film are not damaged and the protrusion of the photoresist film is not left. SOLUTION: This laser cutter is provided with a light source and a light receiving and detecting means for detecting the outer periphery of the semiconductor wafer and a laser light source and a moving means which moves the luminous flux of a laser beam for cutting and cuts the coating film of the wafer by projecting the laser upon the wafer beam along the outer periphery of the wafer. Therefore, a semiconductor wafer coated with such a photoresist film that is not damaged and has no protrusion can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser cutting machine, and more particularly to a laser cutting machine for cutting a coating film covering a semiconductor wafer along the periphery of the semiconductor wafer.

[0002]

2. Description of the Related Art In recent years, in exposing and etching semiconductor wafers, it has been practical to use a dry type photoresist film instead of applying a liquid photoresist. That is, a semiconductor wafer placed on a base film made of PET (polyethylene terephthalate) is covered with a dry photoresist film, and then a PE film is formed thereon.
Covered with a protective film made of T (polyethylene terephthalate),
A photoresist film is formed on the semiconductor wafer so as to enclose it. This work is performed by coating a photoresist film on a semiconductor wafer that is arranged at equal intervals on the base film, and then covering it with a protective film, and a long strip-like lamination with individual semiconductor wafers inserted. A plate is formed. Since this operation is performed in a vacuum, no bubbles or the like remain between the semiconductor wafer and the photoresist film. The band-shaped laminate is cut in the width direction to form a rectangular laminate in which semiconductor wafers are individually covered. In this way, the work required for forming a photoresist film on a semiconductor wafer can be easily performed.

[0003] Prior to exposure processing, the semiconductor wafer must have its protective film removed and the photoresist exposed directly to light. Therefore, the protective film and the base film are removed along the outer edge of the semiconductor wafer, and the photoresist film protrudes and remains at the peripheral portion of the semiconductor wafer so as not to hinder the positioning work in a later process. There is a need to. At that time, extreme care is indispensable so as not to damage the semiconductor wafer and the photoresist film.

[0004]

Conventionally, the removal of the protective film, the base film, and the unnecessary photoresist film has been performed with a blade. The use of the knife has a problem that the semiconductor wafer and the photoresist film may be damaged.

Recently, not only the so-called orientation flat type of the outer edge of the semiconductor wafer but also the so-called V-notch type have been widely used. The outer edge shape of the V notch type has a problem that it includes a line that is bent at a steep angle and is unsuitable for cutting with a knife, and the protrusion of the photoresist film tends to remain.

SUMMARY OF THE INVENTION In view of the above problems, the present invention provides a protective film, a photoresist film, and a base film along an outer edge of a semiconductor wafer without damaging the semiconductor wafer and the photoresist film and protruding the photoresist film. It is an object of the present invention to provide a laser cutting machine that cuts so as not to remain.

[0007]

SUMMARY OF THE INVENTION The present invention is a laser cutting machine for cutting a coated base comprising a base and a coating material for coating the base along a peripheral edge of the base. A light source that emits light that can be transmitted through the coating material; a light receiving position detection unit that receives the light to detect a light receiving position; a laser light source that emits laser light that cuts the coating material; A moving unit for moving an optical axis of light, and a control unit for controlling the moving unit, the light receiving position detecting unit is emitted from the light source,
The control unit receives the light passing through the outside of the peripheral portion of the base, detects the peripheral position of the base, and outputs a peripheral position detection signal. A laser cutting machine is characterized in that an irradiation signal is output to a laser light source and controlled to irradiate the laser light to cut the coating material.

Further, there is provided a laser cutting machine for cutting a coated base comprising a base and a coating material for coating the base along a peripheral edge of the base, the laser cutting machine being capable of being reflected by the base and transmitting the coating material. A light source that emits light, a light receiving position detecting unit that receives the light to detect a light receiving position, a laser light source that emits a laser beam that cuts the coating material, and a movement that moves an optical axis of the laser beam And a control means for controlling the moving means, wherein the light receiving position detecting means receives the light emitted from the light source and reflected by the base, detects the peripheral position of the base, and detects the peripheral position. A position detection signal is output, and the control unit receives the peripheral position detection signal, outputs an irradiation signal to the moving unit and the laser light source, controls the irradiation, and irradiates the laser light to cut the coating material. That Configured as a desirable laser cutting machine according to symptoms.

3. The laser cutting device according to claim 1, further comprising irradiating the laser beam from a peripheral portion of the base to a peripheral portion of the cover base to cut the coating material. Machine was configured as desired.

[0010]

According to the first and second aspects of the present invention, the light beam of the semiconductor laser cuts the protective film, the photoresist film, and the base film along the outer edge of the semiconductor wafer. According to the third aspect of the present invention, the base film is easily removed.

[0011]

FIG. 1 shows a laser cutting machine according to one embodiment of the present invention.
And FIG. FIG. 1 is a conceptual diagram of a laser cutting machine. FIG. 2 is a plan view of the covering substrate. The coating substrate 1 is a laminated plate in which a semiconductor wafer 3, a photoresist film 4, and a protective film 5 are sequentially laminated on a base film 2, and the layers are in close contact with each other and no bubbles or the like are mixed. The planar shape of the covering substrate 1 is a square having a side length of 22 cm, and the semiconductor wafer 3 is located at the center. The semiconductor wafer 3 has a circular shape with a diameter of 20 cm and a thickness of 0.7 mm, and has a so-called orientation flat or a so-called V notch missing portion in a part thereof.

The base film 2 is made of PET (polyethylene terephthalate) having a thickness of 10 to 50 μm, the photoresist film 4 is made of a photosensitive resin film having a thickness of 100 to 200 μm, and the protective film 5 is made of PET (polyethylene terephthalate). It is a film having a thickness of 10 to 50 μm. Although the photoresist film 4 is strongly adhered to the semiconductor wafer 3 so as not to be easily peeled off, the base film 2 and the protective film 5 can be easily peeled off from both the semiconductor wafer 3 and the photoresist film 4. Since the edge 1a of the side of the covering substrate 1 does not have the semiconductor wafer 3, the base film 2, the photoresist film 4, and the protective film 5 are sequentially laminated.

The support base 6 for supporting the covering base 1 is composed of a vertically rotating shaft 7 and a supporting plate 8 which can be moved up and down. I have. The diameter of the support plate 8 is 15 cm, which is smaller than the diameter of the semiconductor wafer 3.

The light source 11 is a tungsten lamp that emits visible light, and is installed below the support plate 8 and opposed to the periphery of the semiconductor wafer 3. The light beam L <b> 1 of the visible light is converged and focused on the point 3 a on the peripheral edge of the semiconductor wafer 3. The photodiode array 12 is 5 mm long, 10
00 element diodes are in parallel. Above the support plate 8, the semiconductor wafer 3 is installed so as to face the peripheral edge point 3 a where the light beam L 1 is focused, and that the parallel direction of the photodiodes is parallel to the diameter direction of the semiconductor wafer 3. . Then, a portion of the light beam L1 that has passed through the point 3a on the periphery of the semiconductor wafer 3 is received, the position of the point 3a on the periphery is detected, and a periphery position detection signal S1 is output.

The laser light source 13 is a carbon dioxide laser.
The wavelength is 10.6 μm and the output is 5 watts. The emitted light beam L2 is guided by an optical system (not shown). The moving device 14 includes a slider 16 on which a reflecting mirror 15 is mounted and the linear motor 1.
7 and the slider 16 is a linear motor 17
Driven by The CDU 18 receives the peripheral position detection signal S1 output from the photodiode array 12, outputs an irradiation signal S2, and outputs the irradiation signal S2.
Control.

Next, the operation will be described. The coating substrate 1 is supported on a support plate 8 such that the center of the semiconductor wafer 3 substantially coincides with the center of the rotation shaft 7 and rotates about the rotation shaft 7. The light beam L1 emitted from the light source 11 is transmitted through the base film 2, the photoresist film 4, and the protective film 5, but is not transmitted through the semiconductor wafer 3. Therefore, the light is blocked inside the peripheral point 3a of the semiconductor wafer 3 and passes outside the peripheral point 3a. Photodiode array 12
Receives the passed light and outputs a peripheral position detection signal S1.

The CDU 18 receives the edge position detection signal S1 and outputs an irradiation signal S2 to the moving unit 14 and the laser light source 13. Point 3a detected by photodiode array 12
Is moving on an arc around the rotation axis with the rotation of the coating substrate, and the light beam L2 must irradiate the position after the movement. Therefore, in the irradiation signal S2, the movement time is corrected for the peripheral position detection signal S1. Further, in order to prevent the semiconductor wafer 3 from being damaged by the light beam L2, the periphery of the photoresist film 4 is set at a distance of 0.1 mm from the periphery of the semiconductor wafer 3.
The correction is performed so as to protrude by about 2 to 0.3 mm.

The mover 14 moves the light beam L2 and outputs the light beam L2.
2 irradiates and cuts the protective film 5, the base film 2, and the photoresist film 4 at the outer edge of the peripheral point 3a. The coating substrate 1 is supported substantially at the center on the support plate 8,
The semiconductor wafer 3
Is cut off from the surroundings. When the cutting and separation of the semiconductor wafer 3 is completed, while the light beam L2 is retracted from the point 3a,
Irradiation is continued to the end 1a of the coating substrate 1 to cut it. Although this operation can be performed before the start of the cutting of the peripheral edge of the semiconductor wafer 3, it is preferable that the cutting of the peripheral edge is completed.

The photoresist film 4 is strongly adhered to the semiconductor wafer 3 so as not to be easily peeled off, and covers the surface of the semiconductor wafer 3 in the same shape. Move to the next process by the robot arm. The base film 2 and the protective film 5 can be easily peeled off from the semiconductor wafer 3 and the photoresist film 4, and the base film 2 is dropped and removed under the support plate 8, and the protective film 5 is removed by suction.

Next, a laser cutting machine according to a second embodiment will be described with reference to FIG. FIG. 3 is an overall view of the laser cutting machine. The same members as those of the embodiment are denoted by the same reference numerals, and the description of the same or similar parts is omitted. The light beam L1 emitted from the light source 11 is reflected on the upper surface of the semiconductor wafer 3 and passes outside the peripheral point 3a. The photodiode array 12 receives the reflected light and outputs a peripheral position detection signal S3. The CDU 18 receives the edge position detection signal S3 output from the photodiode array 21, outputs an irradiation signal S4, and outputs the irradiation signal S4.
Control.

Next, a laser cutting machine according to a third embodiment will be described with reference to FIG. FIG. 4 is an overall view of the laser cutting machine. The same members as those of the first embodiment or the second embodiment are denoted by the same reference numerals, and the description of the same or similar parts is omitted. The coating substrate 1 is a photoresist film 4 on a semiconductor wafer 3.
Is a laminated plate. The light source 11 is below the support plate 8,
The semiconductor wafer 3 is provided so as to face the peripheral portion.
The light beam L <b> 1 of the visible light is converged and focused on the point 3 a on the periphery of the semiconductor wafer 3. Photodiode array 1
Numeral 2 is provided above the support plate 8 and opposed to the peripheral point 3a, detects the position of the point 3a, and outputs a peripheral position detection signal S1. The laser light source 13 emits a light beam L2. The galvano scanner 21 is provided with a reflecting mirror 22. CD
U18 receives the peripheral position detection signal S1, and outputs the irradiation signal S2
To output the galvano scanner 21 and the laser light source 1
3 is controlled.

Next, the operation will be described. Point 3 on the periphery of semiconductor wafer 3 of light flux L1 emitted from light source 11
Passes outside of a. Photodiode array 1
2 outputs the peripheral position detection signal S1 in response to the passed light. The CDU 18 receives the peripheral position detection signal S1 and sends an irradiation signal S2 to the galvano scanner 21 and the laser light source 13.
Is output. The galvano scanner 21 rotates the reflecting mirror 22 with the light beam L2 according to the irradiation signal S2, and the semiconductor wafer 3
The light beam L2 irradiates and cuts the photoresist film 4 at the outer edge of the peripheral point 3a.

In the embodiment, it is needless to say that the coating base may be a laminated plate having another configuration, for example, a configuration of a base film, a semiconductor wafer, a photoresist film, or the like.

[0024]

According to the present invention, the protective film, the photoresist film, and the base film are formed along the outer edge of the semiconductor wafer without damaging the semiconductor wafer and the photoresist film, and no protrusion of the photoresist film remains. Laser cutting machine is provided.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram of a laser cutting machine according to one embodiment of the present invention.

FIG. 2 is a plan view of a covering substrate according to one embodiment of the present invention.

FIG. 3 is a sectional view of a laser cutting machine according to a second embodiment of the present invention.

FIG. 4 is a sectional view of a laser cutting machine according to a third embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Coating base, 2 ... Base film, 3 ... Semiconductor wafer, 3a ... Point, 4 ... Photoresist film,
5: protective film, 11: light source, 12: photodiode array, 13: laser light source, 17: linear motor, 21: galvano scanner

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) // B23K 101: 40 H01L 21/30 577 564Z

Claims (3)

[Claims] 1. A laser cutting machine for cutting a coated base comprising a base and a coating material for coating the base along a peripheral edge of the base, wherein the laser cutting machine is cut off by the base and permeable to the coating material. A light source that emits light, a light receiving position detecting unit that receives the light to detect a light receiving position, a laser light source that emits a laser beam that cuts the coating material, and a movement that moves an optical axis of the laser beam Means, and control means for controlling the moving means, the light receiving position detecting means,
Receiving the light emitted from the light source and passing outside the peripheral portion of the substrate, detecting the peripheral position of the substrate and outputting a peripheral position detection signal, the control means receives the peripheral position detection signal. A laser cutting machine which outputs an irradiation signal to the moving means and the laser light source and controls the irradiation means to irradiate the laser light to cut the coating material. 2. A laser cutting machine for cutting a coated base comprising a base and a coating material for coating the base along a peripheral edge of the base, the laser cutting machine being reflected by the base and transmitting the coating material. A light source that emits light, a light receiving position detecting unit that receives the light to detect a light receiving position, a laser light source that emits a laser beam that cuts the coating material, and a movement that moves an optical axis of the laser beam Means, and control means for controlling the moving means, the light receiving position detecting means,
The light emitted from the light source, the light reflected by the base is received, the peripheral position of the base is detected and a peripheral position detection signal is output, and the control unit receives the peripheral position detection signal, and receives the peripheral position detection signal. A laser cutting machine, wherein an irradiation signal is output to the laser light source and controlled, and the laser light is irradiated to cut the coating material. 3. The laser cutting according to claim 1, wherein the laser beam is irradiated from a peripheral portion of the base to a peripheral portion of the cover base to cut the coating material. Machine.