A gate-quality dielectric system for SiGe metal-oxide-semiconductor devices

Author

Iyer, S.S. ; Solomon, Paul M. ; Kesan, Vijay P. ; Bright, A.A. ; Freeouf, John L. ; Nguyen, Thao N. ; Warren, Alan C.

Author_Institution

IBM Thomas, J Watson Res. Center, Yorktown Heights, NY, USA

Volume

12

Issue

5

fYear

1991

fDate

5/1/1991 12:00:00 AM

Firstpage

246

Lastpage

248

Abstract

The authors present a high-quality dielectric system for use with Si/sub 1-x/Ge/sub x/ alloys. The system employs plasma-enhanced chemical vapor deposited (PECVD) SiO/sub 2/ on a thin (6-8-nm) layer of pure silicon grown epitaxially on the Si/sub 1-x/Ge/sub x/ layer. The buffer layer and the deposited oxide prevent the accumulation of Ge at the oxide-semiconductor interface and thus keep the interface state density within acceptable limits. The Si cap layer leads to a sequential turn-on of the Si/sub 1-x/Ge/sub x/ channel and the Si cap channel as is clearly observed in the low-temperature C-V curves. The authors show that this dual-channel structure can be designed to suppress the parasitic Si cap channel. The MOS capacitors are also used to extract valence-band offsets.<>

Keywords

Ge-Si alloys; dielectric thin films; insulated gate field effect transistors; metal-insulator-semiconductor structures; plasma CVD; semiconductor materials; semiconductor technology; silicon compounds; 6 to 8 nm; MOS capacitors; MOSFETs; PECVD; Si buffer layer; Si cap channel; Si cap layer; Si/sub 1-x/Ge/sub x/ alloys; Si/sub 1-x/Ge/sub x/ channel; Si/sub 1-x/Ge/sub x/-Si-SiO/sub 2/; SiGe MOS devices; dual-channel structure; gate-quality dielectric system; high-quality dielectric system; interface state density; low-temperature C-V curves; valence-band offsets; Buffer layers; Chemicals; Dielectrics; Germanium alloys; Germanium silicon alloys; Interface states; MOS capacitors; Plasma chemistry; Silicon alloys; Silicon germanium;

fLanguage

English

Journal_Title

Electron Device Letters, IEEE

Publisher

ieee

ISSN

0741-3106

Type

jour

DOI

10.1109/55.79571

Filename

79571