Patent · US Expired

Method of and apparatus for evaluating crystal rate in silicon thin film

US5314831A · kind A · utility

20Cited by
4References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 23, 1992
Grant dateMay 24, 1994
Priority date
Expiry dateOct 23, 2012

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L22/12
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Light in an ultraviolet region is applied to a first sample of single-crystalline silicon substrate and a sample of silicon thin film to be evaluated respectively, to obtain wavelength dependency of a ratio (reflection intensity ratio) K(.lambda.) between reflection light intensity values of the samples. A straight line connecting points indicating reflection intensity values at wavelengths 235 nm and 320 nm is obtained to subtract an actual reflection intensity ratio Kr from a virtual reflection intensity ratio Ki provided by the straight line with respect to a wavelength of 270 nm, thereby obtaining an index .DELTA.Ks. In a similar manner, an index .DELTA.Ka is obtained as to a second sample of silicon which is composed of only true amorphous phases. The degree of non-crystallization of the silicon thin film to be obtained is evaluated by comparing the index .DELTA.Ks with the index .DELTA.Ka.

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