Highly reliable ultra-thin SiO/sub 2/ films formed by rapid thermal processing

Author

Fukuda, H. ; Arakawa, T. ; Ohno, S.

Author_Institution

Oki Electr. Ind. Co. Ltd., Tokyo, Japan

fYear

1989

fDate

3-6 Dec. 1989

Firstpage

451

Lastpage

454

Abstract

A reliable method of forming ultrathin SiO/sub 2/ films has been developed by using rapid thermal processing (RTP). In this study, both RTP oxidation (RTO) and RTP cleaning (RTC) are attempted. As a result, the dielectric strength of SiO/sub 2/ film is greatly improved by an RTO-1/RTC/RTO-2 cycle under reduced gas pressure. TDDB (time-dependent dielectric breakdown) measurements show that, with decreasing SiO/sub 2/ film thickness, short-time breakdown (<10/sup -1/ s) decreases drastically below 6 nm. High-resolution TEM (transmission electron microscope) measurements indicate that, by this RTP cycle, an extremely flat SiO/sub 2/-Si interface, ordered within one to two atomic layers, is obtained. Furthermore, in MOS capacitors having ultrathin SiO/sub 2/, the quantum oscillation in the Fowler-Nordheim tunneling current is clearly observed even at 300 K. It is confirmed that the proposed method is very effective in reducing defects such as broken Si-O bonds in bulk SiO/sub 2/ and/or SiO/sub 2/-Si interface.<>

Keywords

electric breakdown of solids; incoherent light annealing; insulating thin films; metal-insulator-semiconductor devices; reliability; semiconductor technology; semiconductor-insulator boundaries; silicon compounds; transmission electron microscope examination of materials; tunnelling; Fowler-Nordheim tunneling current; MOS capacitors; RTO-1/RTC/RTO-2 cycle; RTP; RTP cleaning; RTP cycle; RTP oxidation; TEM; atomic layers; defects; dielectric strength; flat SiO/sub 2/-Si interface; quantum oscillation; rapid thermal processing; reduced gas pressure; reliable method; short-time breakdown; time-dependent dielectric breakdown; ultrathin films; Atomic layer deposition; Atomic measurements; Cleaning; Dielectric breakdown; Dielectric measurements; MOS capacitors; Oxidation; Rapid thermal processing; Thickness measurement; Transmission electron microscopy;

fLanguage

English

Publisher

ieee

Conference_Titel

Electron Devices Meeting, 1989. IEDM '89. Technical Digest., International

Conference_Location

Washington, DC, USA

ISSN

0163-1918

Print_ISBN

0-7803-0817-4

Type

conf

DOI

10.1109/IEDM.1989.74319

Filename

74319