Bipolar transistor characterization apparatus with lateral test probe pads
US6605825B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 14, 2002 |
| Grant date | Aug 12, 2003 |
| Priority date | — |
| Expiry date | Feb 14, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/0002
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Test probe pads are located lateral to, and spaced from, the emitter, base or collector region of a bipolar transistor, preferably on separate pedestals, and connected to their respective transistor regions by air bridges. The probe pads, transistor contacts and air bridges are preferably formed as common metallizations. In the case of an HBT, a gap in the subcollector below the air bridges insulates the test transistor from capacitor loading by the probe pads. The test transistors can be used to characterize both themselves and functional circuit transistors fabricated with the same process on the same wafer by testing at an intermediate stage of manufacture, thus allowing wafers to be discarded without completing the manufacture if their transistors do not meet specifications.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.