Singulation apparatus comprising an imaging device

Patent metadata

Field	Value
Publication number	US-9263352-B2
Application number	US-201414146875-A
Country	US
Kind code	B2
Filing date	Jan 3, 2014
Priority date	Jan 3, 2014
Publication date	Feb 16, 2016
Grant date	Feb 16, 2016

Abstract

Disclosed is a singulation apparatus for cutting a workpiece. The singulation apparatus comprises: i) a processor; ii) at least one chuck device for securing the workpiece to be cut; iii) a cutting device spaced from the at least one chuck device by a separation distance, the cutting device being for cutting the workpiece secured to the at least one chuck device; and iv) an imaging device operable to capture one or more images comprising the cutting device and a reference feature. In particular, the processor is configured to determine a separation distance between the cutting device and the reference feature based on the one or more images as captured by the imaging device, to thereby determine the separation distance between the cutting device and the workpiece as secured to the at least one chuck device.

First claim

The invention claimed is:

1. A singulation apparatus for cutting a workpiece, comprising:
a processor;
at least one chuck device for securing the workpiece to be cut;
a cutting device spaced from the at least one chuck device by a separation distance, the cutting device being for cutting the workpiece secured to the at least one chuck device;
a reference feature that is separate from the workpiece; and
an imaging device operable to capture one or more images comprising the cutting device and the reference feature,
wherein the processor is configured to determine a separation distance between the cutting device and the reference feature based on the one or more images as captured by the imaging device, to thereby determine the separation distance between the cutting device and the workpiece as secured to the at least one chuck device.

2. The singulation apparatus of claim 1 , wherein the reference feature is arranged in relation to the at least one chuck device by a known positional relation.

3. The singulation apparatus of claim 1 , wherein the reference feature is part of the at least one chuck device.

4. The singulation apparatus of claim 1 , wherein the imaging device is a camera.

5. The singulation apparatus of claim 1 , wherein the imaging device is a laser scanner.

6. The singulation apparatus of claim 1 , wherein the cutting device comprises a circular rotatable blade for cutting the workpiece.

7. The singulation apparatus of claim 1 , wherein the processor is configured to determine from the one or more images captured by the imaging device, the number of pixels corresponding to the separation distance between the cutting device and the reference feature, and apply a pixel-distance correlation factor to the determined number of pixels to determine the separation distance between the cutting device and the reference feature.

8. The singulation apparatus of claim 7 , wherein
the cutting device is configured to be positioned to define a known separation distance between the cutting device and the reference feature;
the imaging device is configured to capture one or more images comprising the reference feature and the cutting device spaced from the reference feature by the known separation distance; and
the processor is configured to determine from the one or more images captured by the imaging device, the number of pixels corresponding to the known separation distance between the cutting device and the reference feature, to derive the pixel-distance correlation factor.

9. The singulation apparatus of claim 8 , wherein the known separation distance is 1 mm.

10. A method of determining a separation distance between a workpiece secured to a chuck device and a cutting device for cutting the workpiece in a singulation apparatus, the method comprising the steps of:
capturing one or more images comprising the cutting device and a reference feature, the reference feature being separate from the workpiece; and
determining the separation distance between the cutting device and the reference feature based on the one or more images as captured; and thereby
determining the separation distance between the cutting device and the workpiece as secured to the chuck device.

11. The method of claim 10 , wherein the reference feature is arranged in relation to the chuck device.

12. The method of claim 10 , wherein the reference feature is part of the chuck device.

13. The method of claim 10 , wherein the step of determining the separation distance between the cutting device and the reference feature comprises the steps of:
determining the number of pixels corresponding to the separation distance between the cutting device and the reference feature from the one or more images captured by the imaging device; and
applying a pixel-distance correlation factor to the determined number of pixels to determine the separation distance between the cutting device and the reference feature.

14. The method of claim 13 , further comprising the steps of:
positioning the cutting device to define a known separation distance between the cutting device and a reference feature;
capturing one or more images comprising the reference feature and the cutting device spaced from the reference feature by the known separation distance; and
determining from the one or more images captured, the number of pixels corresponding to the known separation distance between the cutting device and the reference feature, to derive the pixel-distance correlation factor.

15. The method of claim 14 , wherein the known separation distance is 1 mm.

16. A method of calibrating a singulation apparatus, the singulation apparatus comprising i) a cutting device for cutting a workpiece and ii) at least one chuck device for securing the workpiece to be cut, the method comprising the steps of:
positioning the cutting device to define a known separation distance between the cutting device and a reference feature, the reference feature being separate from the workpiece;
capturing one or more images comprising the reference feature and the cutting device spaced from the reference feature by the known separation distance; and
determining from the one or more images captured, the number of pixels corresponding to the known separation distance between the cutting device and the reference feature, to derive a pixel-distance correlation factor.

17. The method of calibrating the singulation apparatus of claim 16 , wherein the known separation distance is 1 mm.

18. The method of calibrating the singulation apparatus of claim 16 , wherein the reference feature is arranged in relation to the at least one chuck device by a known positional relation.

19. The method of calibrating the singulation of claim 16 , wherein the reference feature is part of the at least one chuck device.

Assignees

• Cheng Chi Wah
• Tang Hoi Shuen
• Liu Chun Kit
• Asm Tech Singapore Pte Ltd

Inventors

• Cheng Chi Wah
• Tang Hoi Shuen
• Liu Chun Kit

Classifications

• H10P72/0606

  Position monitoring, e.g. misposition detection or presence detection · CPC title

• H10P72/0428

  Apparatus for mechanical treatment or grinding or cutting · CPC title

• H10P72/53

  using optical controlling means · CPC title

• H10P54/00

  Cutting or separating of wafers, substrates or parts of devices · CPC title

• H10P74/23 Primary

  characterised by multiple measurements, corrections, marking or sorting processes · CPC title