Physical and electrical characteristics of HfN gate electrode for advanced MOS devices

Author

Yu, H.Y. ; Lim, H.F. ; Chen, J.H. ; Li, M.-F. ; Zhu, Chunxiang ; Tung, C.H. ; Du, A.Y. ; Wang, W.D. ; Chi, D.Z. ; Kwong, D.L.

Author_Institution

Dept. of Electr. & Comput. Eng., Nat. Univ. of Singapore, Singapore

Volume

24

Issue

4

fYear

2003

fDate

4/1/2003 12:00:00 AM

Firstpage

230

Lastpage

232

Abstract

In this letter, the physical and electrical properties of physical vapor deposited (PVD) hafnium nitride (HfN) is studied for the first time as the metal gate electrode for advanced MOS devices applications. It is found that HfN possesses a midgap work function in tantalum nitride (TaN)/HfN/SiO/sub 2//Si MOS structures. TaN/HfN stacked metal-gated MOS capacitors exhibit negligible variations on equivalent oxide thickness (EOT), leakage current, and work function upon high-temperature treatments (up to 1000 /spl deg/C), demonstrating the excellent thermal stability of HfN metal gate on SiO/sub 2/. Our results suggest that HfN metal electrode is an ideal candidate for the fully depleted SOI and/or symmetric double gate MOS devices application.

Keywords

MIS devices; MOS capacitors; hafnium compounds; heat treatment; leakage currents; semiconductor device metallisation; thermal stability; vapour deposited coatings; work function; 1000 degC; HfN gate electrode; MOS device; TaN-HfN-SiO/sub 2/-Si; TaN/HfN stacked metal-gated MOS capacitor; TaN/HfN/SiO/sub 2//Si MOS structure; electrical characteristics; equivalent oxide thickness; heat treatment; leakage current; physical vapor deposition; thermal stability; work function; Atherosclerosis; Dielectric substrates; Electric variables; Electrodes; Hafnium; MOS capacitors; MOS devices; Sputtering; Thermal stability; Tin;

fLanguage

English

Journal_Title

Electron Device Letters, IEEE

Publisher

ieee

ISSN

0741-3106

Type

jour

DOI

10.1109/LED.2003.812143

Filename

1206847