By Topic

Ultrathin SiO2 layer with an extremely low leakage current density formed in high concentration nitric acid

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $31
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

3 Author(s)
Kim, Woo-Byoung ; Institute of Scientific and Industrial Research, Osaka University, and CREST, Japan Science and Technology Agency, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan ; Matsumoto, Taketoshi ; Kobayashi, Hikaru

Your organization might have access to this article on the publisher's site. To check, click on this link: 

An ultrathin silicon dioxide (SiO2) layer of 1.2–1.4 nm thickness has been formed by immersion of Si wafers in nitric acid (HNO3) aqueous solutions, and its electrical characteristics and physical properties are investigated as a function of the HNO3 concentration. Measurements of transverse optical and longitudinal optical phonons of Si–O–Si asymmetric stretching vibrational mode for SiO2 indicate that the atomic density of the SiO2 layer increases with the HNO3 concentration. X-ray photoelectron spectroscopy measurements show that the valence band discontinuity energy at the SiO2/Si interface also increases and the concentration of suboxide species decreases with the HNO3 concentration. The leakage current density of the <Al/SiO2/Si(100)> metal-oxide-semiconductor (MOS) diodes with the SiO2 layer formed in HNO3 aqueous solutions decreases with the HNO3 concentration and also decreases by postmetallization annealing (PMA) treatment at 250 °C in 5 vol % hydrogen atmosphere. For the MOS diodes with the SiO2 layer formed in 98 wt % HNO3, the leakage current density measured after PMA is much lower than that for thermally - grown SiO2 with the same thickness and even lower than that for silicon oxynitride with the same effective oxide thickness. The decrease in the leakage current density by PMA is attributed to (i) elimination of interface states, (ii) elimination of slow states, and (iii) increase in the band discontinuity energy at the SiO2/Si interface.

Published in:

Journal of Applied Physics  (Volume:105 ,  Issue: 10 )