Shin-etsu Handotai Co., Ltd.

Fumio Tahara

Wei Feng Qu

Yuuki Ooi

Kiyoshi Mitani

Tsuyoshi Ohtsuki

Ryoji Hoshi

Takatoshi Nagoya

Ken Aihara

Tomosuke Yoshida

Fumitaka Kume

Satoshi Tobe

Naohisa Toda

Shu Sugisawa

A silicon wafer heat treatment method includes: placing a silicon wafer on a SiC jig and into a heat treatment furnace; performing heat treatment on the silicon wafer in the heat treatment furnace in a first non-oxidizing atmosphere; reducing the temperature; and carrying the silicon wafer out of the heat treatment furnace. In the heat reduction step, after the temperature is reduced to the temperature at which the silicon wafer can be carried out of the heat treatment furnace, the first non-oxidizing atmosphere is switched to an atmosphere containing oxygen, an oxide film having a thickness of 1 to 10 nm is formed on the surface of the SiC jig in the atmosphere containing oxygen, and the atmosphere containing oxygen is then switched to a second non-oxidizing atmosphere. A silicon wafer heat treatment method can prevent carbon contamination from a jig and an environment during a heat treatment process.

Silicon wafer heat treatment method

A method for detecting a crystal defect in a silicon single crystal wafer doped with nitrogen, the silicon single crystal wafer whose initial oxygen concentration is 8 ppma (JEIDA) or lower. The method further includes the steps of: making a crystal defect of defect size of 25 nm or smaller apparent and detectable by implanting oxygen into the crystal defect by performing heat treatment on the silicon single crystal wafer in an oxygen atmosphere; and detecting the crystal defect of the silicon single crystal wafer after the heat treatment temperature is set such that, when the ratio between the oxygen solid solubility and the initial oxygen concentration of the silicon single crystal wafer heat treatment is set at &#x3b1;=the oxygen solid solubility/the initial oxygen concentration, &#x3b1; falls within a range from 1 to 3.

Method for detecting crystal defects

The present invention provides a method for manufacturing a silicon single crystal wafer, in which a heat treatment is performed with respect to a silicon single crystal wafer having oxygen concentration of less than 7 ppma and nitrogen concentration of 1&#xd7;10to 1&#xd7;10atoms/cm, which is obtained from a V-region silicon single crystal ingot grown by the Czochralski method, in a non-nitriding atmosphere at 1150 to 1300&#xb0; C. for 1 to 120 minutes. As a result, a method for manufacturing a low-cost silicon single crystal wafer which is applicable to an IGBT by using a V-region wafer that is manufactured by the CZ method which can cope with an increase in diameter, by making a bulk have no defects and by providing a radial resistivity distribution, which is substantially equal to that when the neutron irradiation is effected, without performing the neutron irradiation is provided.

Method for manufacturing silicon single crystal wafer and annealed wafer

The invention provides a method for manufacturing a bonded substrate by bonding a base substrate to a bond substrate through an insulator film, including: a porous layer forming step of partially forming a porous layer or forming a porous layer whose thickness partially varies on a bonding surface of the base substrate; an insulator film forming step of changing the porous layer into the insulator film, and thereby forming the insulator film whose thickness partially varies on the bonding surface of the base substrate; a bonding step of bonding the base substrate to the bond substrate through the insulator film; and a film thickness reducing step of reducing a film thickness of the bonded bond substrate to form a thin-film layer. As a result, there is provided the method for manufacturing a bonded substrate that enables obtaining an insulator film whose thickness partially varies with use of a simple method.

Bonded substrate and manufacturing method thereof

A method for manufacturing a bonded substrate that has an insulator layer in part of the bonded substrate includes: partially forming a porous layer or forming a porous layer whose thickness partially varies on a bonding surface of the base substrate; performing a heat treatment to the base substrate having the porous layer formed thereon to change the porous layer into the insulator layer, and thereby forming the insulator layer whose thickness partially varies on the bonding surface of the base substrate; removing the insulator layer whose thickness varies by an amount corresponding to a thickness of a small-thickness portion by etching; bonding the bonding surface of the base substrate on which an unetched remaining insulator layer is exposed to a bond substrate; and reducing a thickness of the bonded bond substrate and thereby forming a thin film layer.

Method for manufacturing bonded substrate having an insulator layer in part of bonded substrate

A method for manufacturing a silicon single crystal wafer, having at least: a step of preparing a silicon single crystal ingot; a step of slicing the silicon single crystal ingot to fabricate a plurality of sliced substrates; a processing step of processing the plurality of sliced substrates into a plurality of substrates by performing at least one of lapping, etching, and polishing; a step of sampling at least one from the plurality of substrates; a step of measuring surface roughness of the substrate sampled at the sampling step by an AFM and obtaining an amplitude (an intensity) of a frequency band corresponding to a wavelength of 20 nm to 50 nm to make a judgment of acceptance; and a step of sending the substrate to the next step if a judgment result is acceptance or performing reprocessing if the judgment result is rejection.

Method for evaluating oxide dielectric breakdown voltage of a silicon single crystal wafer

A silicon epitaxial layeris grown in vapor phase on a silicon single crystal substratemanufactured by the Czochralski method, and doped with boron so as to adjust the resistivity to 0.02 &#x3a9;&#xb7;cm or below, oxygen precipitation nucleiare formed in the silicon single crystal substrate, by carrying out annealing at 450&#xb0; C. to 750&#xb0; C., in an oxidizing atmosphere, for a duration of time allowing formation of a silicon oxide film only to as thick as 2 nm or below on the silicon epitaxial layeras a result of the annealing, and thus-formed silicon oxide filmis etched as the first cleaning after the low-temperature annealing, using a cleaning solution. By this process, the final residual thickness of the silicon oxide film can be suppressed only to a level equivalent to native oxide film, without relying upon the hydrofluoric acid cleaning.

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Annaka, Japan

Fumio Tahara