Array-based early threshold voltage recovery characterization measurement
US7868640B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 2, 2008 |
| Grant date | Jan 11, 2011 |
| Priority date | — |
| Expiry date | Nov 24, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/3004
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and test circuit provide measurements to aid in the understanding of time-varying threshold voltage changes such as negative bias temperature instability and positive bias temperature instability. In order to provide accurate measurements during an early stage in the threshold variation, a current generating circuit is integrated on a substrate with the device under test, which may be a device selected from among an array of devices. The current generating circuit may be a current mirror that responds to an externally-supplied current provided by a test system. A voltage source circuit may be included to hold the drain-source voltage of the transistor constant, although not required. A stress is applied prior to the measurement phase, which may include a controllable relaxation period after the stress is removed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.