Electrical interconnect integrity measuring method
US5459672A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 5, 1993 |
| Grant date | Oct 17, 1995 |
| Priority date | — |
| Expiry date | Feb 5, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/14
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A method of bond quality monitoring wherein a bonding machine is fitted with a touchdown mechanism including a pair of contacts (23, 24), which normally open upon touchdown of a bonding tool (27) raised and lowered by a bond head carriage (13). As the tool (27) is lowered towards a bonding surface (31), the bonding machine's computer (61) performs a test (103) to sense production of a touchdown signal produced by opening of the contacts (23, 24). If touchdown is sensed, the carriage (13) proceeds to an overtravel position. Upon reaching the overtravel position, a second test (108) is performed to confirm touchdown, and energy is then applied to the bond site. During energy application, the logic state of the touchdown mechanism is checked to ensure that the contacts do not close for example to check for application of inadequate force during bonding. If a contact closure is sensed, the bond site location is logged for further examination such as a nondestructive pull test. When the carriage ascends, the distance it travels before closure of the contacts ( 23, 24) is used as a measure of bond deformation and, hence, bond quality.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.