Impact of tantalum composition in TaC/HfSiON gate stack on device performance of aggressively scaled CMOS devices with SMT and strained CESL

Author

Goto, M. ; Tatsumura, K. ; Kawanaka, S. ; Nakajima, K. ; Ichihara, R. ; Yoshimizu, Y. ; Onoda, H. ; Nagatomo, K. ; Sasaki, T. ; Fukushima, T. ; Nomachi, A. ; Inumiya, S. ; Oguma, H. ; Miyashita, K. ; Harakawa, H. ; Inaba, S. ; Ishida, T. ; Azuma, A. ; Aoy

Author_Institution

Center for Semicond. R&D, Toshiba Corp., Yokohama

fYear

2008

fDate

17-19 June 2008

Firstpage

132

Lastpage

133

Abstract

We report TaC_x/HfSiON gate stack CMOS device with simplified gate 1^st process from the viewpoints of fixed charge generation and its impact on the device performance. Moderate Metal Gate / High-K dielectric (MG/HK) interface reaction is found to be a dominant factor to improve device performance. By optimizing TaC_x composition, fixed charge free TaC_x/HfSiON device is successfully fabricated. Also, we have demonstrated that the strain effect in deeply scaled devices can be enhanced by eliminating the fixed charges in HfSiON, for the first time. Utilizing Stress Memorization Technique (SMT) and strained Contact Etch Stop Layer (CESL), L_g = 35 nm high performance TaC_x/HfSiON devices is achieved.

Keywords

CMOS integrated circuits; etching; hafnium compounds; high-k dielectric thin films; stress effects; tantalum compounds; CMOS devices; SMT; TaC/HfSiON gate stack; device performance; fixed charge generation; metal gate/high-K dielectric interface reaction; strain effect; strained CESL; strained contact etch stop layer; stress memorization technique; tantalum composition; Atherosclerosis; CMOS process; Capacitive sensors; Composite materials; Degradation; Dielectric devices; Dielectric materials; Large scale integration; Research and development; Surface-mount technology;

fLanguage

English

Publisher

ieee

Conference_Titel

VLSI Technology, 2008 Symposium on

Conference_Location

Honolulu, HI

Print_ISBN

978-1-4244-1802-2

Electronic_ISBN

978-1-4244-1803-9

Type

conf

DOI

10.1109/VLSIT.2008.4588591

Filename

4588591