Systematic studies on electronic structures of CuInSe2and the other chalcopyrite related compounds by first principles calculations

✍ Scribed by Maeda, T. ;Takeichi, T. ;Wada, T.

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 213 KB
• Volume: 203
• Category: Article
• ISSN: 0031-8965
• DOI: 10.1002/pssa.200669539

✦ Synopsis

Abstract

We have systematically studied electronic structure of chalcopyrite‐type CuInSe~2~ and the other chalcopyrite compounds, ABX ~2~ (A = Cu, Ag; B = In, Ga, Al; X = Se, S). First‐principles calculations were performed within a density functional theory with the generalized gradient approximation (GGA), using a plane‐wave pseudopotential method. Valence band maximum (VBM) of Cu__BX__ ~2~ is an antibonding state of Cu 3d and Se 4p (S 3p), while conduction band minimum (CBM) is also an antibonding state derived from B n s and Se 4p (S 3p). Theoretical band gap increases at the order of In, Ga, Al and the values of sulfides, Cu__B__ S~2~ were larger than those of the corresponding selenides, Cu__B__ Se~2~. In present study, we found that the lowest unoccupied n s orbital of B atom in the conduction band shift up to higher energy. Therefore, the band gaps of Cu__B__ Se~2~ (Cu__B__ S~2~) increase at the order of In, Ga, Al with shifting of n s orbital for B atom. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)