Impacts of HF etching on ultra-thin core gate oxide integrity in dual gate oxide CMOS technology

Author

Lee, Da-Yuan ; Lin, Horng-Chih ; Chen, Chia-Lin ; Huang, Tiao-Ywan ; Wang, Tahui ; Lee, Tze-Liang ; Chen, Shih-Chang ; Liang, Mong-Song

Author_Institution

Inst. of Electron., Nat. Chiao-Tung Univ., Hsin-Chu, Taiwan

fYear

2003

fDate

24-25 April 2003

Firstpage

77

Lastpage

80

Abstract

In this paper, we investigate the effects of HF etching on the integrity of ultra-thin oxides in dual gate oxide (DGO) CMOS technologies. We found that both the HF concentration in the etching solution and the over etching (OE) time are important parameters that greatly affect the device performance and reliability. Our results indicate that, with a proper over etching period, using a concentrated HF solution results in better ultra-thin gate oxides in terms of reduced defect density, improved device performance and reliability, compared to using diluted HF solution. It is also found for the first time that negative-bias-temperature instability (NBTI) immunity for PMOSFETs is improved by using concentrated HF solutions.

Keywords

CMOS integrated circuits; MOSFET; etching; hydrogen compounds; integrated circuit reliability; semiconductor device reliability; HF; HF concentration; HF etching; PMOSFETs; concentrated HF solution; defect density; device performance; dual gate oxide CMOS technology; etching solution; negative-bias-temperature instability immunity; over etching time; reliability; ultra-thin core gate oxide integrity; CMOS technology; Etching; Fabrication; Hafnium; Laboratories; MOSFETs; Niobium compounds; Semiconductor device manufacture; Titanium compounds; Transconductance;

fLanguage

English

Publisher

ieee

Conference_Titel

Plasma- and Process-Induced Damage, 2003 8th International Symposium

Print_ISBN

0-7803-7747-8

Type

conf

DOI

10.1109/PPID.2003.1200921

Filename

1200921