Shin-Etsu Handotai Co., Ltd.

Shin-Etsu Handotai Company Limited of Japan

Yutaka Kitagawara

Takao Takenaka

Ryoji Hoshi

Masaro Tamatsuka

Susumu Kuwahara

Hiroshi Kubota

Ken Aihara

Tomosuke Yoshida

Hisayuki Saito

Kazuhisa Takamizawa

The present invention provides an evaluation method for a crystal defect in a silicon single crystal wafer based on an infrared laser scattering tomograph method, wherein at least, the silicon single crystal wafer is irradiated with a laser beam, and light that enters the silicon single crystal wafer is scattered by a crystal defect, and the scattered light is detected to evaluate a Direct Surface Oxide Defect (DSOD) and a void defect smaller than the DSOD in the silicon single crystal wafer. As a result, the evaluation method for a crystal defect in a silicon single crystal wafer that can simply and precisely evaluate, e.g., a small DSOD, which can be conventionally evaluated based on a Cu deposition method alone, without requiring a wasteful cost.

Evaluation method for crystal defect in silicon single crystal wafer

A method and apparatus for evaluating an oxygen concentration in a semiconductor silicon single crystal highly doped with boron at a low cost with a high sensitivity and high reproducibility. The single crystal, which is doped with boron of a high concentration of 10.sup.17 atoms/cm.sup.3 or higher, is irradiated with a light having a greater energy than that of bandgap of the semiconductor silicon while holding the single crystal at a temperature of room temperature to 50 K and photoluminescence intensities in the vicinity of a photon energy of 0.96 eV of a photoluminescence spectrum emitted from the single crystal under the above irradiation are measured to evaluate an oxygen concentration in the single crystal.

Method for evaluating oxygen concentrating in semiconductor silicon

A lifetime related quality evaluation method, used with a semiconductor wafer having a semiconductor thin layer over the main surface of a semiconductor substrate, for evaluating the lifetime related quality of the semiconductor thin layer and/or the vicinity thereof, characterized by: generating electron-hole pairs in the vicinity of a surface of the semiconductor thin layer by the use of excitation light having a larger energy than the band gap of a semiconductor to be tested; then detecting the intensity at a particular wavelength of light emitted by recombination of the electron-hole pairs; and evaluating the lifetime related quality of the semiconductor thin layer and/or the vicinity thereof based on the detected intensity. The lifetime related quality evaluation method realizes a non-contact, non-destructive quality evaluation of the epitaxial semiconductor wafer.

Method of evaluating lifetime related quality of semiconductor surface

The height x.sub.i (i=1, 2, . . . , N) of a plurality of measuring points on a silicon wafer from a reference plane is measured by means of an AFM (atomic force microscope), the autocorrelation function R.sub.j represented by the equation below is determined: ##EQU1## Where x denotes: ##EQU2## is determined, an arbitrary number of autocorrelation function R.sub.j with large value from said autocorrelation function R.sub.j are selected, and the microroughness on said silicon wafer is analyzed based on the distances between the point R.sub.j=0 and said selected points R.sub.j 's with large value except for R.sub.j=0.

Method of evaluating silicon wafers

The substitutional carbon concentration in a silicon single crystal is determined by determining by FT-IR the infrared absorbance spectrum using as a reference a substantially carbon-free silicon single crystal having substantially the same degree of free carrier absorption and produced by the same process as the sample. A subtraction factor used in the determination is calculated from the infrared absorbance spectra of the sample and the reference. A subtraction spectrum indicating the difference between the sample and the reference at the relevant wave number for carbon is computed, and the carbon concentration in the sample is determined from the distance of the absorption peak of the subtraction spectrum of the localized vibration of substitutional carbon in the sample from a base line of the subtraction spectrum. An FT-IR carbon concentration determination apparatus embodying the method is also disclosed.

Determining carbon concentration in silicon single crystal by FT-IR

A method and apparatus disclosed by this invention allows determination of the interstitial oxygen concentration in a silicon single crystal to be effected stably and accurately without being appreciably affected by change of the temperature of a sample under test. The interstitial oxygen concentration in the silicon single crystal is determined on the basis of the value of:

Method and apparatus for determination of interstitial oxygen

Spatial distribution of deep level concentration near the surface of a semiconductor wafer is evaluated quickly and accurately by a method which comprises at least a step of scanning the surface of the semiconductor wafer in the X and Y direction with a laser beam for carrier excitation from a laster beam source in accordance with the room-temperature photoluminescence (PL) process thereby measuring the wafer map (M.sub.D) of deep level PL intensity (I.sub.D) and wafer map (M.sub.B) of band edge PL intensity (I.sub.B) in the semiconductor wafer and a step of dividing the wafer map (M.sub.D) of PL intensity (I.sub.D) by the .nu.'th power of the wafer map (M.sub.B) of PL intensity (I.sub.B) {the magnitude of the .nu.'th power presenting the numerical value obtained by empirically confirming the dependence of the band edge PL intensity (I.sub.B) on the power of the excitation laster mean} thereby determining the spatial distribution (M.sub.N) of the relative value of deep level concentration (N.sub.D) and performing the evaluation of the distribution of relative deep level concentration on the basis of the spatial distribution (M.sub.N) of the relative deep level concentration (N.sub.D).

Method for evaluation of spatial distribution of deep level

A heat-treating method for an indium-doped dislocation-free gallium arsenide monocrystal having a low carbon concentration and grown in the Liquid Encapsulated Czochralski method, comprising a two-step heat treatment:

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Gunma, Japan

Yutaka Kitagawara