Effects of Sodium on Cu(In, Ga)Se2-Based Thin Films and Solar Cells
- 1 February 1997
- journal article
- Published by IOP Publishing in Japanese Journal of Applied Physics
- Vol. 36 (2R)
- https://doi.org/10.1143/jjap.36.732
Abstract
Cu(In, Ga)Se2 (CIGS) films were deposited with intentionally incorporated Na2Se by a multi-step process onto SiO x /soda-lime glass substrates at elevated temperatures. The effects of sodium on film properties were investigated using X-ray diffraction, X-ray photoelectron spectroscopy and Hall effect measurements. By the addition of Na2Se, the hole concentration of the CIGS-based films (Ga/(In+Ga) ratio=0.37–0.39) increased dramatically to the 1016–1017 c m -3 range for a wide range of Cu/(In+Ga) ratios from 0.4 to 0.8. The increased hole concentration resulted in improved CIGS-based solar cells with efficiencies of 10–13.5% over an extremely wide Cu/(In+Ga) ratio range of 0.51–0.96. P-type Cu(In, Ga)3Se5 phase films with hole concentrations high enough to be used as absorber layers of photovoltaic devices were obtained for the first time by the Na control technique. The possibility of a new type of solar cell with a ZnO:Al/buffer/ p-Cu(In, Ga)3Se5 heterojunction structure is suggested.Keywords
This publication has 6 references indexed in Scilit:
- Preparation and characterization of Cu(In1−xGax)3Se5 thin filmsApplied Physics Letters, 1995
- Structure, chemistry, and growth mechanisms of photovoltaic quality thin-film Cu(In,Ga)Se2 grown from a mixed-phase precursorJournal of Applied Physics, 1995
- Accelerated publication 17.1% efficient Cu(In,Ga)Se2‐based thin‐film solar cellProgress In Photovoltaics, 1995
- Phase relations in the ternary system Cu-In-SeJournal of Materials Science, 1987
- The phase relations in the Cu,In,Se system and the growth of CuInSe2 single crystalsSolar Cells, 1986
- Analysis of the electrical and luminescent properties of CuInSe2Journal of Applied Physics, 1975