Relationship between passivation properties and band alignment in O3-based atomic-layer-deposited AlOx on crystalline Si for photovoltaic applications. (17th July 2015)

• Record Type: Journal Article
• Authors: Ikeno, Norihiro; Yamashita, Yoshihiro; Oji, Hiroshi; Miki, Shohei; Arafune, Koji; Yoshida, Haruhiko; Satoh, Shin-ichi; Hirosawa, Ichiro; Chikyow, Toyohiro; Ogura, Atsushi
• Is Part Of: Japanese journal of applied physics. Volume 54:Number 8(2015:Aug.)Supplement 1
• Publication Date: 2015-07-17
• Subjects: Physics -- Periodicals; 621.05
• DOI: 10.7567/JJAP.54.08KD19
• Languages: English
• ISSNs: 0021-4922

Abstract

Abstract: The passivation properties and band structures in aluminum oxide (AlO x ) deposited by ozone-based atomic layer deposition (ALD) at room temperature on p-type crystalline silicon were investigated by X-ray photoelectron spectroscopy (XPS). The effective carrier lifetime depends on the thickness of AlO x films, since the field effects induced in the films by fixed charges depend on film thickness. The fixed charges are different by two orders of magnitude between films with thicknesses of 10 and 30 nm. At the 30-nm-thick AlO x /Si interface, the completely accumulated band bending of the Si surface was observed. On the other hand, a thin depletion layer was formed at the 10-nm-thick AlO x /Si interface. From the time-dependent XPS measurements, a hole trap was observed toward AlO x, in which trapping centers existed.