Kabushiki Kaisha Toshiba

Atsuko Kubota

Shuichi Samata

Norihiko Tsuchiya

Yoshiaki Matsushita

Masanori Numano

Moriya Miyashita

Masakatu Kojima

Yoshihiro Ueno

Mokuji Kageyama

Hiroyuki Fukui

Hachiro Hiratsuka

Yoshiaki Ohwada

Makiko Wakatsuki

Provided is a process for producing a semiconductor silicon wafer by which an intrinsic gettering effect can be improved and at the same time the top side can be made free from faults. A silicon ingot is produced and sliced to obtain silicon wafers. Then, a polycrystal silicon depositing film is formed on one side of a silicon wafer, which is subjected to a heat treatment in an inert gas, a reducing gas or a mixture thereof to discharge oxygen from the vicinity of the other side. Alternatively, after discharging oxygen from the silicon wafer by a heat treatment, a polycrystal silicon depositing film may be formed on one side of the silicon wafer.

Semiconductor silicon wafer and process for producing it

Process for producing Semiconductor silicon wafer

There are provided a method of inspecting and evaluating semiconductor substrates, good quality semiconductor substrates, a method of manufacturing good quality semiconductor substrates, and a method of manufacturing semiconductor devices using good quality semiconductor substrates. A semiconductor substrate is processed with aqueous basic solution. In this process, the substrate is dipped in the aqueous solution or exposed to a vapor of the aqueous solution. With this process, the surface of the substrate is selectively etched. The substrate surface after the etching process is radiated with a laser beam to measure a light scattered point density. The quality of the substrate can be judged in accordance with the measured density. A thermal treatment may be carried out before or after processing the substrate with the aqueous basic solution. The thermal treatment considerably changes the fine defect density on the surface of the substrate. In accordance with such a change, the quality of the substrate may be judged. If a substrate judged as having a good quality is used, a semiconductor device having a good quality substrate can be obtained.

Semiconductor substrate, method of manufacturing semiconductor substrate

A system for analyzing a metal impurity at the surface of a single crystal semiconductor comprising: an incident device for allowing X-ray to be incident, at an incident angle less than a total reflection angle, onto the surface of a wafer in the form of a thin plate comprised of a single crystal semiconductor (e.g., silicon); a wafer fixing/positioning stage wherein when it is assumed that the wafer surface is partitioned by a lattice having an interval d, and that the wavelength of the X-ray from the incident device is .lambda., an angle that the X-ray and the wafer surface form is .theta., and an arbitrary integer is n, the stage is adapted to fix the crystal orientation of the wafer so as to satisfy the condition of '2d sin .theta..noteq.n.lambda.', and to allow sample points to which X-ray is incident to be subjected to positioning by a horizontal movement; and analyzing device for measuring a light quantity of a fluorescent X-ray generated as the result of the fact that the incident X-ray excites atoms at the wafer surface to analyze a quantity of the metal impurity attached on the wafer surface under the condition that the Bragg reflection causing measurement noises does not take place.

System for analyzing metal impurity on the surface of a single crystal

First, silicon wafers are formed by cutting silicon monocrystalline ingot into slices. Then back side and main surfaces of the wafers are subjected to lapping and etching processes. Next, the wafers are submerged into substantially pure water and ultrasonic waves are applied to the wafer surface via the water to clean at least one of the surfaces of each of the wafers and form gettering damage on the wafer surface. After this, the main surfaces of the wafers which have been subjected to the cleaning and damage-forming process and on which semiconductor elements are to be formed are polished into mirror finish.

Wafer processsing method for manufacturing wafers having

In a method for predicting a density of micro crystal defects to be generated in a semiconductor element, an infrared absorption spectrum associated with a silicon wafer, which is used for the manufacture of the semiconductor element, is formed by a spectrum forming system. The spectrum has a first oxygen absorption peak at the wavenumber range of 1150 to 1050 cm.sup.-1 and a second oxygen absorption peak at 530 to 500 cm.sup.-1. First and second coefficients indicating oxygen concentrations at the first and second peaks are read by a reading unit. The density of the micro crystal defects are predicted by using a ratio of the first and second coefficients as a monitor.

Method for predicting density of micro crystal defects in semiconductor

Growing community of inventors

Yokohama, Japan

Atsuko Kubota