Automated optical inspection apparatus
US5640199A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 2, 1994 |
| Grant date | Jun 17, 1997 |
| Priority date | — |
| Expiry date | May 2, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/14
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
This invention provides a method and apparatus for automatically locating the bond of a wire to a lead frame and semiconductor chip or similar device as an in-process operation to facilitate in-process inspection. The apparatus includes a wire bonding machine, or similar apparatus, having a movable platform such as an X-Y table for holding semiconductor chips situated in lead frames; a video camera or other optical sensing or imaging device for generating images, which camera is typically positioned over the target chip and lead frame to be bonded; illumination means for illuminating the chip in a lead frame; an image processor capable of summing said absolute difference values, whereby each sum is stored as a difference metric, and digitizing and analyzing the optically sensed images; a bonding mechanism; and a host controller connected to the bonding mechanism, the movable platform, the camera and the image processor. The apparatus generates and stores a pre-bond digital image of the semiconductor chip in the lead frame before bonding has occurred; connects one or more wires between the chip and lead frame by any of a number of means such as ultrasonic bonding, heat bonding, cond…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.