The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 07, 1995
Filed:
Dec. 12, 1991
Yukihiro Kiyota, Kodaira, JP;
Tohru Nakamura, Mitaka, JP;
Takahiro Onai, Ome, JP;
Taroh Inada, Tokyo, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
An impurity diffusion method which can control a surface atomic concentration from a low to a high surface atomic concentration with a good uniformity is provided. Natural oxide is removed from the surface of a semiconductor substrate with a deoxidizing atmosphere gas as a diffusion atmosphere gas in advance, and then an impurity gas is passed thereto, while passing the deoxidizing atmosphere gas thereto, thereby conducting the diffusion. Flow rate or concentration of impurity of the impurity gas is so set that the impurity atomic concentration of the diffusion layer can be controlled by the flow rate or the concentration of impurity of the impurity gas. The impurity atomic concentration of the diffusion layer can be controlled by adjusting the flow rate or concentration of impurity of the impurity gas, and a diffusion layer having a low impurity atomic concentration can be formed. A shallow junction having a depth of not more than 50 nm can be formed.