Sumco Corporation

Olympus Corporation

Shinya Fukushima

Takehiro Tsunemori

Hiroyoshi Kobayashi

Satoru Kikuchi

Osamu Konno

Koichi Maegawa

Hiromu Ikeda

Tsuyoshi Kubota

Mitsuo Yoshihara

Masahiko Mizuta

A method of measuring the concentration of Fe in a p-type silicon wafer by an SPV method enabling improvement in the measurement accuracy for Fe concentrations of 1×10/cmor less. The method of measuring the concentration of Fe in a p-type silicon wafer includes measuring an Fe concentration in the p-type silicon wafer based on measurement using an SPV method. The measurement is performed in an atmosphere in which the total concentration of Na, NH, and Kis 1.750 μg/mor less, and the total concentration of F, Cl, NO, PO, Br, NO, and SOis 0.552 μg/mor less.

Method of measuring concentration of Fe in p-type silicon wafer and SPV measurement apparatus

Provided is a method of measuring the concentration of Fe in a p-type silicon wafer by an SPV method enabling improvement in the measurement accuracy for Fe concentrations of 1&#xd7;10/cmor less. The method of measuring the concentration of Fe in a p-type silicon wafer includes measuring an Fe concentration in the p-type silicon wafer based on measurement using an SPV method. The measurement is performed in an atmosphere in which the total concentration of Na, NH, and Kis 1.750 &#x3bc;g/mor less, and the total concentration of F, Cl, NO, PO, Br, NO, and SOis 0.552 &#x3bc;g/mor less.

Provided is a method of measuring the Fe concentration in a p-type silicon wafer by the SPV method, by which the detection limit for the Fe concentration can be lowered, and the measurement can be performed in a short time. The measurement by the SPV method is performed in a measurement mode in which irradiation with a plurality of lights having mutually different wavelengths is performed during the same period under conditions where (i) Time Between Readings is 35 ms or more and 120 ms or less and Time Constant is 20 ms or more, or Time Between Readings is 10 ms or more and less than 35 ms and Time Constant is 100 ms or more, and (ii) Number of Readings is 12 times or less.

Method of measuring Fe concentration in p-type silicon wafer

An aspect of the present invention relates to a method of evaluating metal contamination in a boron-doped p-type silicon wafer, which comprises measuring over time by a microwave photoconductive decay method a recombination lifetime following irradiation with light of a silicon wafer being evaluated and obtaining information on change over time of the recombination lifetime, and comparing the information on change over time of the recombination lifetime that has been obtained with reference information on change over time that has been obtained by calculation or actual measurement of a recombination lifetime of an Fe-contaminated boron-doped p-type silicon wafer to determine whether or not metal contamination other than Fe is present in the silicon wafer being evaluated.

Method of evaluating metal contamination in boron-doped P-type silicon wafer, device of evaluating metal contamination in boron-doped P-type silicon wafer, and method of manufacturing boron-doped P-type silicon wafer

An appropriate stereoscopic image of a subject is readily acquired. Provided is a stereoscopic endoscope device including two image capture elements spaced apart from each other and disposed at a distal end of an insertion section to be inserted into a subject; an angle changing mechanism that changes a relative angle between optical axes of the image capture elements; a distance sensor that detects the distance from the image capture elements to the subject; and a controller that controls the angle changing mechanism on the basis of the distance detected by the distance sensor.

Stereoscopic endoscope device having mechanism that changes an angle between optical axes of two imaging sensors

Provided is a continuous casting method of a silicon ingot for continuously casting the silicon ingot by arranging, inside an induction coil, a bottomless cold crucible having a part along an axial direction that is circumferentially divided into a plurality of strip elements, forming molten silicon inside the cold crucible through electromagnetic induction heating by the induction coil, and solidifying the molten silicon while pulling it down from the cold crucible, wherein as the cold crucible, used is a cold crucible with Ni&#x2014;B alloy plating on a portion in the inner surface thereof that faces the outer side surface of the molten silicon and the outer surface of the silicon ingot. The method can reduce the damage to the inner surface of the cold crucible, in addition to the contamination of cast ingots with impurities.

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Tokyo, Japan

Shinya Fukushima