Sensor for semiconductor device manufacturing process control
US5293216A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 31, 1990 |
| Grant date | Mar 8, 1994 |
| Priority date | — |
| Expiry date | Dec 31, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L22/12
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A fiber-optic sensor device (210) for semiconductor device manufacturing process control measures polycrystalline film thickness as well as surface roughness and spectral emissivity of semiconductor wafer (124). The device (210) comprises a sensor arm (212) and an opto-electronic interface and measurement box (214), for directing coherent laser energy in the direction of semiconductor wafer (124). Opto-electronic interface/measurement unit (214) includes circuitry for measuring the amounts of laser power coherently reflected in the specular direction from the semiconductor wafer (124) surface, scatter reflected from the semiconductor wafer (124) surface, coherently transmitted in the specular direction through the semiconductor wafer (124), and scatter transmitted through the semiconductor wafer (124). The present invention determines the semiconductor wafer (124) surface roughness and spectral emissivity values using the measured optical powers of incident, specular reflected, scatter reflected, specular transmitted, and scatter transmitted beams.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.