KR20130006305A - Processing apparatus - Google Patents

Abstract

PURPOSE: A processing device is provided to improve productivity by arranging a line sensor in a totally reflected light path to securely recognize a shape of a transparent wafer. CONSTITUTION: A maintaining unit(2) includes an absorbing unit(20) which absorbs an object. A processing unit(3) processes the object maintained in the maintaining unit. A scanner(10) is arranged in a moving path of the object from an attaching and detaching region(A) to an applying region(B) and includes a line light and a line sensor which senses reflected light from the line light. A shape recognizing unit(11) recognizes the shape of the object maintained in the maintaining unit according to information from the scanner. [Reference numerals] (11) Shape recognizing unit

Description

Processing device {PROCESSING APPARATUS}

The present invention relates to a processing apparatus having a function of recognizing a shape of a workpiece.

A plurality of devices, such as ICs and LSIs, are divided by dividing lines and are formed on the surface, and are diced into individual devices and used for various electronic devices. Generally, a cutting blade is used for dicing a semiconductor wafer.

On the other hand, in an optical device wafer in which a plurality of optical devices such as LEDs are formed, an n-type semiconductor and a p-type semiconductor are laminated by epitaxial growth on the surface of a substrate having a high Mohs hardness, such as sapphire, and partitioned by a division schedule line. An optical device is formed. Since the optical device wafer formed in this way is difficult to be cut by the cutting blade, a division scheduled line is processed by laser light irradiation, and divided into individual optical devices, and applied to various electric devices such as a lighting device and a backlight of a liquid crystal television. It is used (for example, refer patent document 1).

In a processing apparatus for dividing a wafer by cutting the wafer or irradiating laser light, shape recognition means for recognizing the shape of the wafer in order to detect a region to be processed or to specify a target region in detecting a region to be processed. , The alignment of the processing position is performed with high accuracy based on the recognized shape of the wafer, and appropriate processing is performed (for example, refer to Patent Document 2).

Japanese Patent Application Publication No. Hei 10-305420 Japanese Patent No.3173052

However, since this shape recognition means is a structure which picks up the whole wafer using a CCD camera in the state which stopped the holding means which hold | maintained the wafer, it requires a lot of time for shape recognition, and it is low in device production efficiency. There is a problem.

In the case where the wafer is made of an opaque material such as silicon, the shape of the wafer can be recognized by scanning using diffused reflected light. In the case of a wafer formed of a transparent material such as a sapphire substrate, for example, diffused reflected light There is a problem that the shape of the wafer cannot be recognized because it is difficult to capture.

SUMMARY OF THE INVENTION The present invention has been made in view of such a problem, and in the processing apparatus for processing a wafer, it is an object of the present invention to smoothly recognize a shape of a wafer to improve production efficiency and to recognize a shape even for a transparent wafer. .

The present invention provides at least a holding means for holding a workpiece, a processing means for processing a workpiece held by the holding means, and an alignment means for detecting an area to be imaged by processing the workpiece held by the holding means. A detachable region with respect to a processing apparatus provided with a retaining means movable between a working region which is a region where the workpiece is acted upon by the processing means and a detachable region that is a region where detachment of the workpiece is performed. A scanner disposed in the movement path of the workpiece from the to the working area, and shape recognition means for recognizing the shape of the workpiece held in the holding means by the information from the scanner, wherein the scanner includes line illumination and line illumination. And a line sensor for capturing the reflected light, the incident angle of the light irradiated from the line illumination on the upper surface of the workpiece Is set to the reflected angle, the line sensor is disposed in a total internal reflection light path.

As processing means, the laser processing means provided with at least the laser oscillator which oscillates a laser beam, and the condenser which collects the laser beam oscillated by the laser oscillator to the workpiece hold | maintained by the holding means is mentioned as an example.

In the present invention, since the scanner is disposed in the movement path of the workpiece from the detachable region to the working region, the workpiece is held by the scanner and the shape recognition means while the workpiece held in the holding means moves from the detachable region to the working region. The shape is recognized. Therefore, since it is not necessary to stop the movement of the holding means for recognizing the shape of the workpiece, the productivity of the device can be improved.

In addition, since the incident angle of the light irradiated from the line illumination is set to the angle totally reflected on the upper surface of the workpiece, and the line sensor is disposed in the path of the totally reflected light, the shape can be reliably recognized even for a transparent wafer such as sapphire. have.

1 is a perspective view illustrating an example of a laser processing apparatus.
2 is a schematic diagram showing the configuration of a scanner.
3 is a perspective view showing a state in which a wafer is adhered to a tape and supported by a frame.
4 is a perspective view showing the movement of the wafer when recognizing the shape of the wafer.
It is explanatory drawing which shows the state which recognizes the shape of a wafer.

The laser processing apparatus 1 shown in FIG. 1 is a kind of the processing apparatus of this invention, and is comprised so that a laser processing may be performed by the processing means 3 with respect to the to-be-processed object hold | maintained by the holding means 2. As shown in FIG.

The holding means 2 is provided with the adsorption | suction part 20 which adsorb | sucks a to-be-processed object. The adsorption | suction part 20 is formed of porous members, such as porous ceramics, for example, and the upper surface is formed flat. In addition, when the workpiece W adheres to the tape T and the ring-shaped frame F adheres to the peripheral edge of the tape T as shown in FIG. The fixing part 21 for fixing F) is arrange | positioned.

The laser processing apparatus 1 has a detachable region A which is a region where the workpiece is attached or detached to the holding means 2, and an action region B which is a region where the workpiece is acted upon by the processing means 3. The holding means 2 is comprised so that a movement in the X-axis direction between the detachable area A and the action area B is possible.

The detachable area A is provided with a cassette 4 for accommodating a plurality of workpieces and a carrying-in / out means 5 for carrying out the workpieces from the cassette 4 and carrying the workpieces into the cassette 4. have. Behind the cassette 4, the provisional placing area 6 which is the area where the workpiece | work carried out from the cassette 4 and the workpiece carried in the cassette 4 is temporarily arrange | positioned is located, In the vicinity, the 1st conveyance means 7a which conveys a to-be-processed object between the holding means 2 and the provisional placement area | region 6 is provided.

In the rear side of the detachable area A, the washing | cleaning means 8 which wash | cleans the to-be-processed object is arrange | positioned. Moreover, above the washing | cleaning means 8, the 2nd conveying means 7b which conveys a to-be-processed object between the holding means 2 and the washing | cleaning means 8 is arrange | positioned.

The processing means 3 is arranged in the action region B. The processing means 3 is provided with the irradiation head 30 which radiates a laser beam downward, and the light collector 31 is provided in the lower end of the irradiation head 30. As shown in FIG. The processing means 3 is equipped with the laser oscillator 32 which oscillates a laser beam, the laser beam oscillated by the laser oscillator 32 is sent to the irradiation head 30, and the laser beam is condenser 31 The structure condenses on the workpiece. The processing means 3 is movable in the Y-axis direction.

Above the moving path from the detachable area A of the holding means 2 to the working area B, the alignment means 9 for detecting the region to be processed by imaging the workpiece held in the holding means 2. This is arranged. The alignment means 9 is provided with the imaging part 90.

The scanner 10 is disposed on the side closer to the detachable region A than the imaging unit 90 as above the moving path from the detachable region A to the working region B of the holding means 2. The scanner 10 is electrically connected to a shape recognizing means 11 for recognizing the shape of the workpiece held by the holding means 2 for reading the information output from the scanner 10. The shape recognizing means 11 is provided with a CPU, a memory, and the like. In addition, the image acquired from the scanner 10 and the image acquired by the imaging unit 90 can be displayed on the display 12.

As shown in FIG. 2, the scanner 10 is line illumination 100 which irradiates light linearly with respect to the to-be-processed object hold | maintained by the holding means 2, and is comprised by the lighting apparatuses, such as LED, aligned in the Y-axis direction. And an image sensor are arranged in parallel with the line illumination 100, and the line sensor 101 which captures the reflected light from a to-be-processed object is provided.

The line sensor 101 is located on the extension of the line illumination 100 in the X-axis direction. The incident angle α of the incident light 102a emitted from the line light 100 and the reflection angle β of the reflected light 102b reflected from the workpiece are variable, and the line sensor 101 irradiates from the line light 100. It is arrange | positioned in the position which can capture the reflected light in the to-be-processed object of the processed light.

The wafer W shown in FIG. 3 is an example of the workpiece to be processed using the laser processing apparatus 1, and is a region partitioned by the division scheduled line S formed vertically and horizontally on the surface W1 of the transparent sapphire substrate. An optical device wafer having an optical device D formed thereon. The tape T adheres to the back surface W2 of the wafer W. As shown in FIG. The ring-shaped frame F is adhered to the periphery of the tape T, and the wafer W is supported by the frame F through the tape T. As shown in FIG. The wafer W is formed almost circularly, and the notch N is formed in a part of the outer periphery.

In this way, the wafer W integrated with the frame F is accommodated in the cassette 4 shown in FIG. Then, the frame F is pulled out by the carry-in / out means 5, so that the wafer W is disposed in the provisional placement area 6, and thereafter, by the first transport means 7a, the detachable area A is removed. The wafer W is sucked and held by the suction unit 20, and the frame F is fixed by the fixing unit 21.

Next, as shown in FIG. 4, the holding means 2 moves to the action area | region B side (in the arrow C direction), and sets the wafer W under the scanner 10, and makes it pass slowly. As shown in FIG. 5, incident light 102a is irradiated toward the surface W1 of the semiconductor wafer W from the line illumination 100 which comprises the scanner 10. As shown in FIG. At this time, the incident angle α is set such that the incident light 102a is totally reflected at the surface W1 of the wafer W according to the refractive index inherent in the material of the wafer W. As shown in FIG. The line sensor 101 is disposed in the path of the totally reflected reflected light 102b.

In this way, the incident light 102a from the line illumination 100 is totally reflected on the surface W1 of the wafer W while moving the wafer W in the X-axis direction, and the line sensor 101 sequentially reflects the light ( When 102b) is captured and scanned, the pixel information is transmitted to the shape recognizing means 11 for each line in the Y-axis direction. In the shape recognizing means 11, by recognizing the color of the pixel for each line, the coordinates of the boundary between the wafer W and the holding means 2 are obtained, and the shape of the wafer W is clearly defined based on the coordinate information. I can recognize it. For example, in FIG. 5, in the scan when the X coordinate of the line sensor 101 is X ₁ , it is recognized that the Y coordinate of the outline of the wafer W is Y ₄ and Y ₁₆ . Similarly, the shape recognition means 11 can recognize the shape of the wafer W by sequentially obtaining the coordinate information of the outline of the wafer W while moving the holding means 2 in the X axis direction.

In the example of FIG. 5, the X coordinate of one end in the X-axis direction of the wafer W is X ₀ , the X coordinate of the other end is X _n , and the Y coordinate of one end of the wafer W in the Y-axis direction is Y ₀ , the Y coordinate of the other end is Y _n . Accordingly, it is recognized that the wafer W exists in the range of X ₀ to X _n and Y coordinate to Y ₀ to Y _n . Moreover, from each coordinate which comprises the outline of the wafer W, the wafer W is formed in substantially circular shape, and the position where the notch N is formed is also recognized.

Thus, since the laser processing apparatus 1 arrange | positioned the scanner 10 in the movement path | route of the to-be-processed object from the detachable area | region A to the action area | region B, the wafer W hold | maintained by the holding means 2 The shape of the wafer W can be recognized while moving from the detachable area A to the working area B. FIG. Therefore, since it is not necessary to stop the movement of the holding means 2 for shape recognition, productivity can be improved.

In addition, since the scanner 10 is configured to totally reflect the light emitted from the line illumination 100 on the surface W1 of the wafer W, and to capture the reflected light by the line sensor 101, for example, sapphire or glass and the like. The shape can also be recognized reliably also about the wafer formed from the same transparent material.

When the shape of the wafer W is recognized, the holding means 2 holding the wafer W moves in the X-axis direction without stopping in that state, so that the wafer is directly under the imaging unit 90 shown in FIG. (W) is positioned. Then, the wafer W in which the region existing by the shape recognizing means 11 becomes clear is picked up by the imaging unit 90 and divided by the alignment means 9 through image processing such as pattern matching. The predetermined line S (see Fig. 3) is detected. The imaging unit 90 is arranged on the downstream side in the movement direction of the wafer W than the scanner 10, and the shape recognition means 11 recognizes the region where the wafer W exists in advance, so that the image is to be divided. The line S can be detected smoothly.

And the condenser 31 is positioned on the detected extension line of the X-axis direction of the division plan line S, and the holding means 2 which hold | maintained the wafer W in that state further moves to an X-axis direction, The laser beam is irradiated from the condenser 31, for example, the laser beam is condensed inside the wafer W, and a modified layer is formed therein.

Further, while the holding means 2 is reciprocated in the X-axis direction, the machining means 3 is indexed and transferred in the Y-axis direction by the interval of the adjacent scheduled dividing line S, and the laser dividing line S is sequentially irradiated. Is performed, a modified layer is formed along all the division scheduled lines S in the same direction. If the laser irradiation is repeated in the same manner after the holding means 2 is rotated by 90 degrees, the modified layer is formed along the division scheduled lines S vertically and horizontally. In addition, when performing the ablation process which forms a groove in the surface W1 of the wafer W, a laser beam is condensed on the surface W1.

In this way, when an external force that extends in the plane direction is applied to the wafer W having the modified layer formed therein along the division scheduled line S, the division scheduled line S is broken and divided into individual optical devices. .

In the said embodiment, although the transparent sapphire wafer was mentioned as an example of a to-be-processed object, this invention can be used also for the process of a to-be-processed workpiece.

In addition, although the laser processing apparatus was demonstrated as an example as a processing apparatus, it is not limited to this. For example, as another processing apparatus, there exists a cutting apparatus which cuts and cuts the cutting blade which rotates at high speed to a to-be-processed object.

W: wafer W1: surface
S: Divided line D: Device
W2: Backside T: Tape
F: frame 1: laser processing device
A: detachable area B: working area
2: holding means 20: adsorption part
21: fixed part 3: processing means
30: irradiation head 31: condenser
32: laser oscillator 4: cassette
5: Import / Export means 6: Placement area
7a: first conveying means 7b: second conveying means
8: cleaning means 9: alignment means
90: imaging unit 10: scanner
100: line illumination 101: line sensor
102a: incident light 102b: reflected light
11: shape recognition means

Claims (2)

At least holding means for holding the workpiece, processing means for processing the workpiece held by the holding means, and alignment means for detecting an area to be processed by imaging the workpiece held by the holding means; In the processing apparatus in which the said holding means is movable between the action area | region which is a area | region where a to-be-processed object is acted by the said processing means, and the detachable area | region which is a area | region where the removal and detachment of the workpiece | work to and from the said holding means are performed, WHEREIN:
A scanner disposed in the movement path of the workpiece from the detachable region to the working region;
Shape recognition means for recognizing the shape of the workpiece held in the holding means in accordance with the information from the scanner
And,
The scanner has a line light and a line sensor for capturing the reflected light of the line light, the incident angle of the light irradiated from the line light is set to an angle totally reflected on the upper surface of the workpiece, the line in the path of the totally reflected light The processing device in which the sensor is placed. The method according to claim 1, wherein the processing means,
A laser oscillator for oscillating a laser beam,
A condenser which condenses the laser beam oscillated by the laser oscillator on the workpiece held by the holding means.
Processing apparatus which is a laser processing means provided with at least.

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