Method of marking semiconductors
US4133918A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 16, 1977 |
| Grant date | Jan 9, 1979 |
| Priority date | — |
| Expiry date | May 16, 1997 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41F31/02
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A non-contacting, non-clogging, electro-mechanically operated marking device or inker for continuous or intermittently marking a semiconductor wafer die is disclosed together with a method of operating the device. The marking device has an ambient pressure ink reservoir within which is mounted a thin, capillary filament guide tube. A length of filament such as, fishline, is positioned within the tube and secured at one end to the plunger of a solenoid. The distal end of the filament is driven out of the capillary tube by the solenoid to force a small amount of the marking fluid or ink out of the reservoir and onto the die without the filament contacting the die. The solenoid coil is energized by a current pulse having a first current level and a second current level that is less than the first current level. The second current level provides a short holding current for the solenoid to prevent spattering of the marking fluid.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.