Method and apparatus for die bonding

• US 4,913,335 A
• Filed: 03/08/1989
• Issued: 04/03/1990
• Est. Priority Date: 09/01/1988
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Yoshida, Masaharu
• Primary Examiner(s): Godici, Nicholas P.
• Assistant Examiner(s): Heinrich, Samuel M.
• Application Number:
  US07/320,513
• Time in Patent Office: 391 Days
• Field of Search: 228/103, 228/180.2, 228/62, 228/9, 228/47, 269/903, 269/56, 269/58, 221/155, 221/163, 221/167
• US Class Current: 228/103
• CPC Class Codes: H01L 21/67138 Apparatus for wiring semiconductor or solid state device
• CPC Class Codes: Y10S 269/903 Work holder for electrical circuit assemblages or wiring systems

Abstract

Disclosed is a method for die bonding, comprising the steps of arranging a wafer having a multiplicity of mutually separated semiconductor chips vertically and near a lead frame which is conveyed horizontally, and picking up each of the semiconductor chips from the wafer and bonding the same onto the lead frame.

Claims

1. A method of die bonding comprising:

orienting a semiconductor wafer in a first plane, the wafer including a multiplicity of mutually separated chips, near a lead frame which is conveyed in a second plane orthogonal to said first plane;

determining whether each of the semiconductor chips is defective or non-defective at a first position of said wafer;

moving the wafer to a second position in the first plane along a direction lying in the second plane; and

picking up each of the non-defective semiconductor chips from the wafer and bonding each of the non-defective chips onto a respective lead frame.

2. A method according to claim 1 including rotating a semiconductor chip in the first plane, after being picked up from the respective wafer, for bonding onto said lead frame.

3. A die bonding apparatus comprising:

conveying means for conveying lead frames in a second plane;

holding means for holding a semiconductor wafer in a first plane orthogonal to the second plane near the lead frames, the wafer including a multiplicity of mutually separated chips;

moving means for moving said holding means between first and second positions along a direction lying in the second plane;

a sensor for optically detecting the semiconductor chips when said holding means is in the first position and for generating a sensor signal in response to the detection of each chip;

pattern recognition means for determining, in response to the sensor signal, whether each of the chips is non-defective or defective; and

semiconductor chip moving means for picking up each of the non-defective semiconductor chips from the wafer held by said holding means in the second position and for bonding each of the non-defective chips onto a respective lead frame.

4. A die bonding apparatus according to claim 3 wherein said holding means includes an X-Y moving stage for moving said wafer within the first plane.

5. A die bonding apparatus according to claim 3 wherein said semiconductor chip moving means includes a pickup head for picking up a said semiconductor chip and a motor for rotating said pickup head.

6. A die bonding apparatus according to claim 5 wherein said motor rotates said pick up head within a third plane perpendicular to the first and second planes.

7. A die bonding apparatus according to claim 3, wherein said optical sensor is an ITV camera.

8. A die bonding apparatus according to claim 3, wherein said moving means is a cylinder.

9. A die bonding apparatus comprising:

conveying means for conveying lead frames in a second plane;

first and second holding devices disposed serially along a direction lying in the second plane near the lead frames, said first and second holding devices for holding a semiconductor wafer in a first plane orthogonal to the second plane, the wafer including a multiplicity of mutually separated chips;

a sensor for optically detecting the semiconductor chips when the wafer is held by said first holding device and for generating a sensor signal in response to the detection of each chip;

pattern recognition means for determining, in response to the sensor signal, whether each of the chips is non-defective or defective; and

semiconductor chip moving means, in the vicinity of said second holding device, for picking up each of the non-defective semiconductor chips from the wafer held by said second holding device and for bonding each of the non-defective chips onto a respective lead frame.

10. A die bonding apparatus according to claim 9 wherein said semiconductor chip moving means includes a pick up head for picking up a semiconductor chip and a motor for rotating said pick up head.

11. A die bonding apparatus according to claim 10 wherein said motor rotates said pick up head within a third plane perpendicular to the first and second planes.

12. A die bonding apparatus according to claim 9 wherein said optical sensor is an ITV camera.

13. A die bonding apparatus according to claim 9 comprising wafer transferring means for transferring said wafer held by said first holding device to said second holding device.

14. A die bonding apparatus according to claim 9 wherein said first and second holding devices include respectively first and second X-Y moving stages for moving said wafer within the first plane perpendicular to said lead frame.

15. A die bonding apparatus according to claim 13 wherein said wafer transferring means is a robot hand.