Low temperature control of rapid thermal processes
US6130415A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 22, 1999 |
| Grant date | Oct 10, 2000 |
| Priority date | — |
| Expiry date | Apr 22, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/67248
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
An apparatus for processing a semiconductor substrate mounted in a thermal processing chamber includes a heating system for heating the substrate, which includes lamps facing a front side of the substrate and a power supply system providing power to at least one of the lamps with a DC power component and an AC power component at a selected frequency. The AC power component is a selected fraction of the DC power component. The apparatus also has a sensor facing a back side of the substrate for providing a detected signal indicative of measured radiation from the back side of the substrate. A lock-in system provides a lock-in signal indicative of a magnitude of an AC component of the detected signal at the selected frequency in response to the detected signal and a reference signal at the selected frequency. A processing system is adapted to determine a transmitted portion of the measured radiation that is transmitted through the substrate based upon the lock-in signal, the detected signal and the selected fraction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.