JP2002011641A - Image pickup mechanism of cutting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image pickup mechanism of a cutting device capable of preventing adhesion of contaminant flying during cutting to an object lens. SOLUTION: The object lens opposite to the surface of a work to be machined held on a chuck table 3 and cut is provided. The photographing mechanism for a cutting device is provided to photograph the surface of the work to be machined and comprises a closing cover to cover the periphery of the object lens and have a lower part being opened; and an on-off cover 52 constituted operably between a closing position where an opening 331 of the closed cover is closed and an opening position where an opening 331 of a closed cover is released.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image pickup mechanism of a cutting device, and more particularly to an image pickup mechanism of a cutting device for picking up an image of a surface of a workpiece held on a chuck table.

[0002]

2. Description of the Related Art For example, a cutting apparatus for cutting a semiconductor wafer or the like includes a microscope and a CCD camera for detecting a region to be cut of a workpiece such as a semiconductor wafer or confirming a state of a cutting groove. And the like. This imaging mechanism is generally arranged at a position close to the cutting area.

[0003]

However, since the cutting device performs cutting while supplying cutting water to the cutting portion, cutting water containing cutting chips generated by the cutting is scattered as contamination. The scattered contamination adheres to the objective lens of the microscope constituting the imaging mechanism. As a result, there arises a problem that a region to be cut imaged through the objective lens is erroneously detected or a state of the cut groove is erroneously recognized.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and a main technical problem thereof is to provide an image pickup mechanism of a cutting device which can prevent contamination scattered during cutting from adhering to an objective lens. It is in.

[0005]

According to the present invention, there is provided, in accordance with the present invention, an object lens provided with an objective lens which is held on a chuck table and faces a surface of a workpiece to be cut. An imaging mechanism of a cutting device for imaging the surface of the objective lens, comprising: a hermetic cover covering the periphery of the objective lens and having a downward opening; and shutter means for opening and closing the opening of the hermetic cover. An imaging mechanism for a cutting device is provided.

The shutter means includes an opening / closing lid operable between a closed position for closing the opening of the sealing cover and an opening position for opening the opening of the sealing cover; And an actuator for selectively positioning the actuator. A ring illumination mechanism is provided in the closed cover along the outer periphery of the objective lens and irradiates light to the surface of the workpiece. The shutter means opens and closes the lower part of the ring illumination mechanism. I do. It is desirable to have air supply means for supplying air into the closed cover, and to have air ejection means for ejecting air to the imaging area of the workpiece held on the chuck table. Is desirable.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of an image pickup mechanism of a cutting device constituted according to the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a perspective view of a dicing apparatus as a cutting apparatus equipped with an imaging mechanism constructed according to the present invention. The dicing device in the illustrated embodiment includes a device housing 2 having a substantially rectangular parallelepiped shape. In the apparatus housing 2, a chuck table 3 for holding a workpiece is provided so as to be movable in a cutting feed direction indicated by an arrow X. Chuck table 3
Comprises a suction chuck support 31 and a suction chuck 32 mounted on the suction chuck support 31.
A workpiece, for example, a disc-shaped semiconductor wafer is held on a mounting surface, which is a surface of the suction chuck 32, by a suction means (not shown). The chuck table 3 is configured to be rotatable by a rotation mechanism (not shown).

The dicing apparatus in the illustrated embodiment has a spindle unit 4 as cutting means. The spindle unit 4 is mounted on a moving base (not shown) and adjusted to move in a direction indicated by an arrow Y which is an indexing direction and in a direction indicated by an arrow Z which is a cutting direction.
1 comprises a rotating spindle 42 rotatably supported by a rotating drive mechanism (not shown) and a cutting blade 43 mounted on the rotating spindle 42.

The dicing apparatus in the illustrated embodiment includes a cassette 6 for stocking a semiconductor wafer 5 as a workpiece, a workpiece carrying-out means 7, a workpiece carrying means 8, a cleaning means 9, and a cleaning / transporting means. Means 10 are provided. The semiconductor wafer 5 is mounted on a frame F by a tape T, and is housed in the cassette 6 while being mounted on the frame 51. Further, the cassette 6 is placed on a cassette table 61 which is arranged so as to be able to move up and down by elevating means (not shown).

The dicing apparatus according to the illustrated embodiment has a suction chuck 3 constituting the chuck table 3.
The imaging of the surface of the workpiece held on the surface of No. 2 detects the area to be cut by the cutting blade 43,
An imaging mechanism 20 for checking the state of the cutting groove is provided. This imaging mechanism 20 is made up of optical means such as a microscope and a CCD camera. The imaging mechanism 20 will be described later in detail. Also, the dicing device
A display unit 11 for displaying an image captured by the image capturing mechanism 20 is provided.

Next, the processing operation of the above dicing apparatus will be briefly described. The semiconductor wafer 5 mounted on the frame 51 housed at a predetermined position of the cassette 6 (hereinafter, the semiconductor wafer 5 mounted on the frame F is simply referred to as the semiconductor wafer 5) is moved by a cassette table (not shown) by elevating means (not shown). 61 is positioned at the carry-out position by moving up and down. Next, the workpiece unloading means 7 moves forward and backward, and unloads the semiconductor wafer 5 positioned at the unloading position to the workpiece mounting area 12. The semiconductor wafer 5 carried out to the workpiece mounting area 12 is
The workpiece is transported to the mounting surface of the suction chuck 32 constituting the chuck table 3 by the turning operation of the workpiece transfer means 8 and is suction-held by the suction chuck 32. The chuck table 3 holding the semiconductor wafer 5 by suction in this manner is moved to immediately below the imaging mechanism 20. When the chuck table 3 is positioned directly below the image pickup mechanism 20, the image pickup mechanism 20 detects a cutting line (street) formed on the semiconductor wafer 5, and adjusts the movement of the spindle unit 4 in the direction of the arrow Y which is the indexing direction of the spindle unit 4. Precision alignment work is performed.

Thereafter, the chuck table 3 holding the semiconductor wafer 5 by suction is moved in a direction indicated by an arrow X (a direction perpendicular to the rotation axis of the cutting blade 43), which is a cutting feed direction, so that the chuck table 3 is held by the chuck table 3. The semiconductor wafer 5 is cut along a predetermined cutting line (street) by the cutting blade 43. That is, the cutting blade 43 is mounted on the spindle unit 4 which is moved and adjusted in the direction indicated by the arrow Y which is the indexing direction and the direction indicated by the arrow Z which is the cutting direction, and is rotationally driven. Is moved along the lower side of the cutting blade 43 in the cutting feed direction, so that the semiconductor wafer 5 held on the chuck table 3 is cut by the cutting blade 43 along a predetermined cutting line (street). In this cutting, there are a case where a cutting groove such as a V-groove having a predetermined depth is formed and a case where cutting is performed along a cutting line (street). When the semiconductor wafer 5 is cut along a cutting line (street), the semiconductor wafer 5 is divided into semiconductor chips. The divided semiconductor chips do not fall apart due to the action of the tape T, and the frame F
The state of the semiconductor wafer 5 mounted on is maintained. After the cutting of the semiconductor wafer 5 is completed in this manner, the chuck table 3 holding the semiconductor wafer 5
Is first returned to the position where the semiconductor wafer 5 is suctioned and held, and the suction holding of the semiconductor wafer 5 is released here. Next, the semiconductor wafer 5 is transported to the cleaning means 9 by the cleaning and transporting means 10, where it is cleaned. The semiconductor wafer 5 thus cleaned is transferred to the workpiece transfer means 8.
Thus, the workpiece is carried out to the work placement area 12. And
The semiconductor wafer 5 is accommodated in a predetermined position of the cassette 6 by the workpiece carrying-out means 7.

Next, the image pickup mechanism 20 will be described with reference to FIGS. The imaging mechanism 20 in the illustrated embodiment includes a macro imaging mechanism 20a and a micro imaging mechanism 20b. Macro imaging mechanism 20a
Has a microscope 21a mounted on a movable base 23 with an objective lens 211a at the lower end, and a CCD camera 22a connected to the microscope 21a. The microscopic imaging mechanism 20b also includes a microscope 21b provided with an objective lens 211b at the lower end and mounted on the moving base 23, and a microscope 21b.
And a CCD camera 22b connected to the camera. The movable base 23 is mounted on the stationary support plate 24 so as to be movable in a vertical direction along a guide rail (not shown). The imaging mechanism 20 in the illustrated form includes a feed mechanism 25 for vertically moving the movable base 23 along a guide rail (not shown) of the stationary support plate 24 and adjusting the focal points of the objective lenses 211a and 211b. ing. Feed mechanism 2
Reference numeral 5 denotes a well-known screw-rod type operating mechanism, which moves the moving base 23 in the vertical direction by driving the pulse motor 251 to rotate forward and reverse.

The objective lenses 211a and 211b are respectively provided with sealing covers 30a and 3
0b is attached. The sealing covers 30a and 30b have substantially the same configuration, and will be mainly described below with reference to FIGS. The sealing covers 30a and 30b are composed of a cylindrical side wall 31, an upper wall 32 mounted on an upper end of the side wall 31, and a lower wall 3 mounted on a lower end of the side wall 31.
3 and an inner cylinder 34 disposed inside the side wall 31. A fitting hole 321 corresponding to the outer diameter of the objective lenses 211a and 211b is provided at the center of the upper wall 32. This fitting hole 321 has a hole diameter of the objective lens 211a.
Therefore, the fitting hole 321 is press-fitted to the outer periphery of the objective lenses 211a and 211b. Opening 3 in lower wall 33
A tapered support surface 3 which is inclined upward and supports a ring illumination mechanism to be described later is provided at an opening edge thereof.
32 are formed. The inner cylinder 34 includes a cylindrical portion 341 that forms an upper portion and a reduced diameter portion 342 that forms a lower portion and is gradually reduced in diameter. The lower end of the inner cylinder 34 has an opening 331 formed in the lower wall 33. Has been reached. Inner cylinder 34
Is formed by a tapered surface corresponding to the tapered support surface 332. The inner cylinder 34 thus formed has an opening 343 below the reduced diameter portion 342 constituting the lower portion thereof.
It is designed to take in light.

The sealing cover 30a in the illustrated embodiment
And 30b include a ring illumination mechanism 40 disposed between the side wall 31 and the inner cylinder 34 along the outer circumference of the objective lenses 211a and 211b. Ring illumination mechanism 4
Reference numeral 0 denotes an annular optical fiber support member 41 having a plurality of fitting holes 411, and a plurality of optical fibers 42 each having a front end fitted into a plurality of fitting holes 411 formed in the optical fiber support member 41. The optical fiber supporting member 41 is sandwiched and held between the tapered supporting surface 332 formed on the lower wall 33 and the outer peripheral surface (tapered surface) of the reduced diameter portion 342 constituting the inner cylinder 34. ing. The base ends of the plurality of optical fibers 42 are arranged to face a light source (not shown) through an optical fiber insertion tube 43 (see FIGS. 2 and 3) mounted on the side wall 31. The ring illumination mechanism 40 configured as described above irradiates the imaging region 300 of the semiconductor wafer 5 as a workpiece held on the chuck table 3 through the 331 formed on the lower wall 33.

As shown in FIG. 2 and FIG. 3, the image pickup mechanism 20 in the illustrated embodiment
A shutter means 50 for opening and closing an opening 343 provided in the reduced diameter portion 342 constituting the inner cylinder 34 of the inner wall 34b and an opening 331 formed in the lower wall 33 is provided. The shutter means 50 in the illustrated embodiment includes a lid support member 51, an opening / closing lid 52, and a rotary actuator 53 for operating the opening / closing lid 52, as shown in FIG. The lid support member 51 includes a support portion 511 and a mounting portion 512. The support portion 511 includes a horizontal portion 511a and the horizontal portion 511.
a vertical portion 511b formed by bending upward from the front end of a
It consists of The mounting portion 512 is formed upright from the rear end of the support portion 511, and has a long hole 512 for attachment.
a, an elongated hole 512a. The lid supporting member 51 thus configured is provided with bolts 531 and 531 in the mounting long holes 512a and the long holes 512a provided in the mounting portion 512.
And the bolts 531 and 531 are connected to the movable base 2.
3 is mounted on the movable base 23 by screwing into screw holes 231 and 231 provided at the end of the base 3.

An opening / closing lid 52 is arranged below the supporting portion 511 constituting the lid supporting member 51, and a rotary actuator 53 for operating the opening / closing lid 52 is arranged above the supporting portion 511. A shaft connecting member 5 is provided on the upper surface of one end of the opening / closing lid 52.
The shaft connecting member 521 and the rotor shaft of the rotary actuator 53 mounted on the upper surface of the support portion 511 are connected to each other. As the rotary actuator 53, various types of actuators such as a compressed air operated type, an electric motor type, and a rotary solenoid type can be used.

Shutter means 5 in the illustrated embodiment
Reference numeral 0 denotes a front cover 54 mounted on the front surface of the vertical portion 511b of the support portion 511 constituting the lid support member 51. The front cover 54 has an elongated hole 541 and an elongated hole 5 at one end.
41 are provided, bolts 532 and 532 are inserted through the elongated holes 541 and 541, and the bolts 532 and 532.
32 is attached to the vertical portion 511b by screwing into the screw holes 511c and 511c provided in the vertical portion 511b of the support portion 511. At the lower end of the front cover 54, there is provided a horizontal portion 542 bent rearward, and the horizontal portion 542 is positioned slightly below the opening / closing lid 52. A notch 543 through which the optical fiber insertion tube 43 is inserted is provided at the other end of the front cover 54.
Is provided. In the shutter means 50 configured as described above, the opening / closing lid 52 is rotated about the shaft connecting member 521 by operating the rotary actuator 53, and the shutter means 50 forms the inner cylinder 34 of the closed covers 30a and 30b. A closed position (a position shown by a two-dot chain line in FIG. 4) for closing the openings 343 and 343 provided in the diameter portions 342 and 342 and the openings 331 and 331 formed in the lower walls 33 and 33, and the openings 343 and 343 and the opening 33
1 and 331 are selectively positioned at an open position (the position shown by the actual battle in FIG. 4).

Continuing the description with reference to FIGS. 2 and 3, on the front surface of the front cover 54, pipe support members 63a and 63b to which an air supply pipe 61 and an air jet nozzle 62 are respectively attached are mounted. . Air supply pipe 61 attached to pipe support members 63a and 63b
And 61 are through holes 5 provided in the front cover 54.
44 and 544, the closed covers 30a and 30b
Through holes 312 and 312 provided in the side walls 31 and 31 and through holes 343 and 343 (see FIG. 4) provided in the inner cylinders 34 and 34 of the closed covers 30a and 30b. This air supply pipe 61
And 61 are connected to an air supply source (not shown). Therefore, the air supply pipes 61 and 61 and the air supply source (not shown) are connected between the inner cylinders 34 and 34 of the closed covers 30a and 30b and the objective lenses 211a and 211b. It functions as air supply means for supplying air to the space formed between them. On the other hand, the air ejection nozzles 62, 62 are disposed with their ends facing the imaging area 300 of the semiconductor wafer 5 as a workpiece held on the chuck table 3. The air ejection nozzles 62, 62 are connected to an air supply source (not shown). Therefore, the air ejection nozzles 62, 62 and the air supply source (not shown) are connected to an imaging region 300 of the workpiece held on the chuck table 3.
It functions as an air ejecting means for ejecting air to blow off foreign matters such as water droplets to clean the imaging area.

The image pickup mechanism 20 in the embodiment shown in the drawing is configured as described above, and its operation will be described below. At the time of cutting, the opening / closing lid 52 has the closed cover 30a,
A closed position that closes the openings 343 and 343 provided in the reduced-diameter portions 342 and 342 constituting the inner cylinder 34 of the 30b and the openings 331 and 331 formed in the lower walls 33 and 33 (the position indicated by a two-dot chain line in FIG. 4). ), And through the air supply pipes 61, 61, the sealing covers 30a, 30
Air is supplied to the space formed between the inner cylinders 34, 34b and the objective lenses 211a, 211b. In this way, the objective lenses 211a and 211b are covered with the hermetic covers 30a and 30b, and the reduced diameter portion 3 forming the inner cylinder 34 of the hermetic covers 30a and 30b.
Since the openings 343 and 343 provided in the openings 42 and 342 are closed by the opening / closing lid 52, the cutting water containing contaminants does not adhere to the objective lenses 211a and 211b even when scattered during cutting. Therefore, the surface of the workpiece can always be accurately imaged through the objective lenses 211a and 211b, and image processing such as pattern matching can be smoothly performed without erroneous recognition. Further, at the time of cutting, air is supplied to the space formed between the inner cylinders 34, 34 of the closed covers 30a, 30b and the objective lenses 211a, 211b through the air supply pipes 61, 61, so that the inside of the closed covers 30a, 30b is Is higher than the outside pressure, so that contamination does not enter the closed covers 30a, 30b from the gap between the open / close lid 52 and the closed covers 30a, 30b. In the illustrated embodiment, the lower wall 3 of the sealing cover 30a, 30b is located below the ring illumination mechanism 40.
The openings 331 and 331 formed in the opening and closing lids
The cutting water containing contaminants does not adhere to the ring illumination mechanism 40 even when scattered during cutting.

On the other hand, when the imaging mechanism 20 takes an image of the surface of the workpiece, the opening / closing lid 52 is attached to the sealing cover 30a.
An opening position (a position indicated by a solid line in FIG. 4) that opens the openings 343 and 343 provided in the reduced diameter portions 342 and 342 constituting the inner cylinder 34 of the 30b and the openings 331 and 331 formed in the lower walls 33 and 33. And ejects air to the imaging area 300 of the workpiece held on the chuck table 3 through the air ejection nozzles 62, 62. At this time, the inner tubes 34, 34 of the closed covers 30a, 30b and the objective lens 21 are passed through the air supply pipes 61, 61.
It is preferable that air is supplied to a space formed between the first and second substrates 1a and 211b, and the air is jetted through the openings 343 and 343 to the imaging region 300 of the workpiece. As described above, when the surface of the workpiece is imaged by the imaging mechanism 20, air is blown into the imaging area 300 of the workpiece, so that cutting water and the like adhering to the imaging area of the workpiece are eliminated. Therefore, it is possible to accurately recognize the state of, for example, the cut groove that is imaged.

Although the present invention has been described based on the illustrated embodiment, the present invention is not limited to the embodiment. For example, in the embodiment, the example in which the imaging mechanism 20 is configured by the two imaging mechanisms of the macro imaging mechanism 20a and the micro imaging mechanism 20b has been described, but the number of imaging mechanisms may be one.

[0024]

The imaging mechanism of the cutting device according to the present invention is constructed as described above, and has the following operation and effect.

That is, since the imaging mechanism of the cutting apparatus according to the present invention includes a closed cover that covers the periphery of the objective lens and is open at the lower side, and shutter means for opening and closing the opening of the closed cover, the cutting mechanism can be used during cutting. The periphery of the objective lens is covered by a sealing cover, and the lower opening of the sealing cover is closed by an opening / closing lid. Therefore, even if cutting water containing contaminants scatters during cutting, it does not adhere to the objective lens. As a result, the surface of the workpiece can always be accurately imaged through the objective lens, and image processing such as pattern matching can be smoothly performed without erroneous recognition.

[Brief description of the drawings]

FIG. 1 is a perspective view of a dicing device, which is a cutting device equipped with an imaging device configured according to the present invention.

FIG. 2 is a perspective view of an imaging device configured according to the present invention.

FIG. 3 is an exploded perspective view showing constituent members of the imaging apparatus shown in FIG. 2;

FIG. 4 is a cross-sectional view showing a main part of the imaging device shown in FIG.

FIG. 5 is a bottom view of a sealing cover included in the imaging device shown in FIG. 2;

[Explanation of symbols]

 2: Device housing 3: Chuck table 31: Suction chuck support 32: Suction chuck 4: Spindle unit 41: Spindle housing 42: Rotating spindle 43: Cutting blade 5: Semiconductor wafer 6: Cassette 7: Workpiece unloading means 8: Workpiece conveying means 9: Cleaning means 10: Cleaning conveying means 11: Display means 20: Imaging mechanism 20a: Macro imaging mechanism 20b: Microscopic imaging mechanism 21a, 21b: Microscope 211a, 211b: Objective lenses 22a, 22b: CCD Camera 23: Moving base 24: Stationary support plate 25: Feeding mechanism 251: Pulse motor 30a, 30b: Sealing cover 31: Sealing cover side wall 32: Sealing cover upper wall 33: Sealing cover lower wall 331: Opening 34: Inner cylinder of hermetic cover 40: Ring illumination mechanism 41: Ring Optical fiber support member of light mechanism 42: Optical fiber of ring illumination mechanism 50: Shutter means 51: Lid support member of shutter means 52: Open / close lid of shutter means 53: Rotary actuator of shutter means 54: Front cover of shutter means 61: Air supply Pipe 62: Air jet nozzle 63a, 63b: Pipe support member

Claims (5)

[Claims] 1. An imaging mechanism of a cutting device, comprising: an objective lens which is held on a chuck table and faces a surface of a workpiece to be cut and which captures an image of the surface of the workpiece. An imaging mechanism for a cutting device, comprising: a closed cover having a lower opening; and shutter means for opening and closing the opening of the closed cover. 2. An opening / closing lid operable between a closed position for closing an opening of the hermetic cover and an open position for opening the opening of the hermetic cover; The imaging mechanism of a cutting device according to claim 1, further comprising a position and an actuator selectively positioned at the open position. 3. A ring illumination mechanism is provided in the closed cover along the outer periphery of the objective lens and irradiates light to the surface of the workpiece, and the shutter means is provided in the ring illumination mechanism. The cutting device according to claim 1, wherein the lower portion is opened and closed. 4. The cutting device according to claim 1, further comprising an air supply unit that supplies air into the closed cover. 5. The cutting device according to claim 1, further comprising an air ejection unit that ejects air to an imaging area of the workpiece held on the chuck table.