US 5,508,207 AGranted

Method of annealing a semiconductor wafer in a hydrogen atmosphere to desorb surface contaminants

AssigneeSumitomo Sitix Corporation

InventorsMasataka Horai, Naoshi Adachi, Hideshi Nishikawa, Masakazu Sano

Life of this patent

Estimating the term…

Loading patent…

Abstract

The present invention provides a method of manufacturing a semiconductor wafer whereby (1) deterioration of a micro-roughness in a low temperature range in hydrogen atmospheric treatment and increase of resistivity due to outward diffusion of an electrically active impurity in a high temperature range are prevented; (2) in the heat treatment in a hydrogen gas atmosphere, the concentration of gas molecules in the atmosphere, such as water, oxygen and the like, are brought to 5 ppm or less in water molecule conversion; and a reaction is suppressed in which a substrate surface is oxidized unequally and the micro-roughness deteriorates; and (3) the same kind of impurity as the electrically active impurity contained in a Si substrate is mixed into the atmosphere and the outward diffusion of the impurity in the vicinity of the Si substrate surface is prevented to prevent variation of the resistivity.

Claims1

Dependent claims

In a method of manufacturing a semiconductor wafer, a method of heat treatment of a semiconductor silicon substrate during loading of the semiconductor silicon substrate in a furnace having an internal temperature of greater than room temperature by 300.degree. C. or less, said method of heat treatment comprising:

(a) loading the semiconductor silicon substrate onto a loading table which is in turn loaded in the furnace and thereafter replacing atmospheric gas in the furnace with a nitrogen gas atmosphere;
(b) subsequently replacing the nitrogen gas atmosphere with a hydrogen gas atmosphere and raising the internal temperature to 750.degree. C. to 800.degree. C. in the hydrogen gas atmosphere, and maintaining this temperature for 10 to 30 minutes to desorb water and oxygen molecules, wherein replacement with the hydrogen gas atmosphere makes total concentration of water and oxygen molecules less than 5 ppm in water conversion;
and (c) raising the internal temperature in the hydrogen gas atmosphere to a temperature in a range of from 950.degree. C. to 1200.degree. C. for heat treatment of the semiconductor silicon substrate in the hydrogen gas atmosphere.

Dependencies are inferred from the claim text.

Facts

Application: 08/199,170Filed 26 Apr 1994
Priority: JP 4-19657629 Jun 1992
Granted: 16 Apr 1996
Term ends: Not estimatedThe source records don’t support an estimate.

Classification10 codes

H10P 95/94
Generic processes or apparatus for manufacture or treatments not covered by the other groups of this subclass: hydrogenation or deuterisation,…
H10P 36/03
Gettering within semiconductor bodies: within silicon bodies
H10P 95/402
Treatments of semiconductor bodies to modify their internal properties, e.g. to produce internal imperfections: of silicon bodies
Y10S 117/906
Single-crystal, oriented-crystal, and epitaxy growth processes; non-coating apparatus therefor: special atmosphere other than vacuum or inert