Semiconductor pick-and-place machine automatic calibration apparatus
US5237622A · kind A · utility
36Cited by
6References
14Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Dec 4, 1991 |
| Grant date | Aug 17, 1993 |
| Priority date | — |
| Expiry date | Dec 4, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K13/089
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An apparatus and method of automatically performing a calibration of the accuracy of placement of semiconductor chips or devices by a pick-and-place machine. The parts are placed on an adhesive-backed glass plate that has calibrated black marks whose dimensions match those of a specific part lead footprint. A gray scale camera mounted on the machine above the inverted glass plate records and sends a signal to a machine computer identifying the coordinates of exposed part silver lead area. The computer calculates part placement error and sends error data to a CRT or camera screen and alarm to alert an operator.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.