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US 5,171,708 AGranted
Method of boron diffusion into semiconductor wafers having reduced stacking faults
AssigneeShin-Etsu Handotai Co., Ltd.
InventorsMasatake Katayama, Shoichi Fujiya, Isao Moroga, Masaru Shinomiya
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Abstract
A method of diffusing boron into semiconductor wafers is disclosed which essentially includes boron deposition and boron diffusion. The deposition is performed from 900.degree. to 1,000.degree. C. and the diffusion at a temperature of 890.degree. to 1000.degree. C. Oxidation induced stacking faults are greatly reduced.
Claims4
A method of diffusing boron into semiconductor wafers, comprising the steps of:
- (a) applying a boron source into a semiconductor wafer;
- (b) calcining the source at a temperature from 450.degree. to 800.degree. C. and in an oxygen atmosphere of lower than 20% by volume in concentration;
- (c) performing boron deposition at a temperature from 900.degree. to 1,000.degree. C. and in a nitrogen atmosphere;
- (d) removing a boron glass layer from the wafer;
- and
- (e) thereafter, effecting boron diffusion at a drive-in charge temperature of 890.degree. to 1,000.degree. C.
3 more elements
Dependencies are inferred from the claim text.