Band alignment and photovoltaic effect of epitaxial α-PbO thin films. (17th June 2015)

• Record Type: Journal Article
• Authors: Majima, Eishi; Kozuka, Yusuke; Uchida, Masaki; Nakamura, Masao; Kawasaki, Masashi
• Is Part Of: Applied physics express. Volume 8:Number 7(2015:Jul.)
• Publication Date: 2015-06-17
• Subjects: Physics -- Periodicals; Technology -- Periodicals; 621.05
• DOI: 10.7567/APEX.8.074001
• Languages: English
• ISSNs: 1882-0778

Abstract

Abstract: To explore a p-type semiconductor lattice-matched with perovskite transition-metal oxides, we have grown α-PbO(001) thin films on (Nb-doped) SrTiO3 (001) and GdScO3 (110) substrates by pulsed laser deposition. The photovoltaic effect in a Au/α-PbO/Nb:SrTiO3 heterojunction is enhanced compared with that in a Au/Nb:SrTiO3 Schottky junction. The band alignment is deduced from photocurrent action spectra. We conclude that α-PbO facilitates the separation of electron–hole pairs generated at the interface of the SrTiO3 side in the ultraviolet light region and of the α-PbO side in the visible light region. Our results indicate that α-PbO is a promising candidate for photovoltaic heterojunctions involving strongly correlated oxides.