US 5,314,831 AGranted

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

AssigneeDainippon Screen Mfg. Co., Ltd.

InventorsSadao Hirae, Noriyuki Kondo, Seiichiro Sato

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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.

Claims11

Dependent claims

A method of evaluating a crystal rate in an objective silicon film including a crystal phase and an amorphous phase, said method comprising the steps of:

(a) preparing a first sample of at least one single-crystal silicon and a second sample of pure amorphous silicon;
(b) applying ultraviolet light to said first sample to obtain a first reflection intensity Ic of said ultraviolet light reflected by said first sample;
(c) applying said ultraviolet light to said second sample to obtain a second reflection intensity Ia of said ultraviolet light reflected by said pure amorphous silicon;
(d) applying said ultraviolet light to said objective silicon film that is being evaluated to obtain a third reflection intensity Is of said ultraviolet light reflected by said objective silicon film;
(e) comparing said first and second reflection intensities Ic and Ia with each other to obtain a first index value .DELTA.Ka;
(f) comparing said first and third reflection intensities Ic and Is with each other to obtain a second index value .DELTA.Ka;
and
(g) comparing said first and second index values .DELTA.Ka and .DELTA.Ks with each other to evaluate said crystal rate in said objective silicon film.

5 more elements

Dependencies are inferred from the claim text.

Facts

Application: 07/965,996Filed 23 Oct 1992
Priority: JP 3-30682024 Oct 1991
Granted: 24 May 1994
Term ends: Not estimatedThe source records don’t support an estimate.

Classification5 codes

G01N 21/8422
Systems specially adapted for particular applications: investigating thin films, e.g. matrix isolation method
G01N 21/33
Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry:…
H10P 74/203
Characterised by the properties tested or measured, e.g. structural or electrical properties: structural properties, e.g. testing or measuring…
G01N
Investigating or analysing materials by determining their chemical or physical properties