Patent · US Expired

Emissivity correction apparatus and method

US4919542A · kind A · utility

118Cited by
8References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 27, 1988
Grant dateApr 24, 1990
Priority date
Expiry dateApr 27, 2008

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01J2005/0074
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Radiation detectors and method measure the emissivity of a remote, heated semiconductor wafer in the presence of ambient radiation. Incident radiation within a selected waveband from a controlled source intermittently radiates the remote wafer, and reflected radiation therefrom is detected in synchronism with the intermittent incident radiation to yield output indications of emissivity of the wafer under varying processing conditions. The temperature of the wafer is monitored by another radiation detector (or detectors) operating substantially within the same selected waveband, and the temperature indications thus derived are corrected in response to the output indications of emissivity to provide indications of the true temperature of the wafer.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.