Title :
CIGS solar cells using a novel window Zn1-xMgxO film
Author :
Negami, T. ; Minemoto, Takashi ; Hashimoto, Yo
Author_Institution :
Matsushita Electr. Ind. Co. Ltd., Kyoto
Abstract :
The authors propose a new window layer of Zn1-xMgx O thin films with a controllable bandgap as an alternative window layer to a CdS film. Measurements of valence band offset and bandgap indicate that a conduction band offset of Zn1-xMgxO/CIGS layers can be controlled by Mg content of the Zn1-xMgxO film. They fabricated CIGS solar cells consist of an ITO/Zn1-xMgxO/CIGS/Mo/Glass structure. The Zn1-xMgxO/CIGS solar cells show performance close to that of the cells using CdS films, when the conduction band of Zn1-xMgxO is higher than that of CIGS. An appropriate conduction band offset of Zn1-xMgxO/CIGS layers decreases the recombination via defects at the interface between majority carriers. Control of conduction band offset has an effect on improving an efficiency of Cd free CIGS solar cells
Keywords :
conduction bands; copper compounds; electron-hole recombination; energy gap; gallium compounds; indium compounds; magnesium compounds; semiconductor device measurement; semiconductor device testing; solar cells; valence bands; zinc compounds; CIGS solar cells; Cu(In,Ga)Se2 solar cells; CuInGaSe2; Zn1-xMgxO window layer; ZnMgO; bandgap measurements; conduction band offset; controllable bandgap; defects; majority carriers; photovoltaic performance; recombination; valence band offset measurements; Conductive films; Glass; Optical films; Photonic band gap; Photovoltaic cells; Plasma measurements; Plasma temperature; Spectroscopy; Transistors; Zinc;
Conference_Titel :
Photovoltaic Specialists Conference, 2000. Conference Record of the Twenty-Eighth IEEE
Conference_Location :
Anchorage, AK
Print_ISBN :
0-7803-5772-8
DOI :
10.1109/PVSC.2000.915923
