Title :
Direct measurement of conduction miniband structure in superlattice by visible-light photoemission spectroscopy
Author :
Ichihashi, Fumiaki ; Shimura, Daisuke ; Nishitani, Kenji ; Kawaguchi, Tatsuki ; Kuwahara, Masashi ; Ito, Takao ; Harada, Shingo ; Katsuno, Hiroyasu ; Tagawa, Masaki ; Ujihara, Toru
Author_Institution :
Dept. of Mater. Sci. & Eng., Nagoya Univ., Nagoya, Japan
Abstract :
We have proposed a novel angle-resolved photoemission spectroscopy to measure the conduction electrons emitted from a surface with negative electron affinity state. We call this method visible-light photoemission spectroscopy (VPS). In the present study, the conduction miniband structure formed in a superlattice was evaluated by the VPS method. As a result, we succeeded to obtain the dispersion of the miniband. In addition, the effective mass of the miniband was quantitatively determined from the observed dispersion. Therefore, we believe that VPS is a quite powerful tool for the evaluation of intermediate-band solar cells.
Keywords :
aluminium compounds; conduction bands; effective mass; electron affinity; gallium arsenide; indium compounds; photoelectron spectra; semiconductor quantum wells; semiconductor superlattices; InGaAs-AlGaAs; angle-resolved photoemission spectroscopy; conduction electrons; conduction miniband structure; effective mass; miniband dispersion; negative electron affinity state; superlattice; visible-light photoemission spectroscopy; Dispersion; Energy measurement; Epitaxial growth; Epitaxial layers; Indexes; Optical variables measurement; Thickness measurement; intermediate-band solar cells; negative electron affinity surface; photoemission spectroscopy; superlattice structure;
Conference_Titel :
Photovoltaic Specialist Conference (PVSC), 2014 IEEE 40th
Conference_Location :
Denver, CO
DOI :
10.1109/PVSC.2014.6925534
