Sumco Corporation

Ryuji Ohno

Masataka Hourai

Yasuo Koike

Kei Matsumoto

Shin Uchino

Hisao Iga

An aspect of the present invention relates to a method of evaluating metal contamination in a semiconductor sample by DLTS method, which includes obtaining a first DLTS spectrum by measuring a DLTS signal while varying a temperature, the DLTS signal being generated by alternatively and cyclically applying to a semiconductor junction on a semiconductor sample a reverse voltage Vto form a depletion layer and a weak voltage Vto trap carriers in the depletion layer; obtaining a second DLTS spectrum by measuring a DLTS signal while varying a temperature, the DLTS signal is being generated by cyclically applying the Vto the semiconductor junction; obtaining a differential spectrum of the first DLTS spectrum with a correction-use spectrum in the form of the second DLTS spectrum or a spectrum that is obtained by approximating the second DLTS spectrum as a straight line or as a curve.

Method of evaluating metal contamination in semiconductor sample and method of manufacturing semiconductor substrate

An aspect of the present invention relates to a method of analyzing an iron concentration of a boron-doped p-type silicon wafer by a SPV method, which comprises subjecting the wafer to Fe&#x2014;B pair separation processing by irradiation with light and determining the iron concentration based on a change in a minority carrier diffusion length following the separation processing. The iron concentration is calculated with a calculation equation comprising a minority carrier diffusion length Lmeasured after the separation processing, a minority carrier diffusion length Lmeasured after a prescribed time has elapsed following measurement of L, and dependence on time of recombination of Fe&#x2014;B pairs separated by the separation processing. The calculation equation is derived by assuming that the irradiation with light causes boron atoms and oxygen atoms in the wafer to form a bonded product, and by assuming that the bonded product has identical influences on Land L.

Method of analyzing iron concentration of boron-doped P-type silicon wafer and method of manufacturing silicon wafer

A method of evaluating a silicon wafer includes obtaining first surface distribution information indicating an surface distribution of photoluminescence intensity on a surface of a silicon wafer; after obtaining the first surface distribution information, subjecting the silicon wafer to a thermal oxidation treatment, and then obtaining second surface distribution information indicating an surface distribution of photoluminescence intensity on the surface of the silicon wafer; obtaining difference information for the first surface distribution information and third surface distribution information, with the third surface distribution information having been obtained by correcting the second surface distribution information with a correction coefficient of less than 1; and based on the difference information obtained, evaluating an evaluation item selected from the group consisting of absence or presence of oxygen precipitates and surface distribution of oxygen precipitates in the silicon wafer being evaluated.

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Saitama, Japan

Ryuji Ohno