Electronic Materials Letters , vol. 4, no. 1, pp.13-18, March, 2008

DOI :

Effect of Cu Content on the Photovoltaic Properties of Cu(In,Ga)Se₂ Solar Cells Prepared by the Evaporation of Binary Selenide Sources

Doo Youl Lee, Min Sik Kim, Liudmila Larina, and Byung Tae Ahn^*
Korea Advanced Institute of Science and Technology

Abstract : A Cu(In,Ga)Se₂ light-absorbing layer was prepared by a three-stage process employing the evaporation of In₂Se₃, Ga₂Se₃, and Cu₂Se. The Cu content in the layer was adjusted by controlling the third-stage evaporation time. A sturdy n-CdS/p-CIGS junction was realized when the Cu content in Cu_x(In_0.66Ga_0.34)Se₂ was approximately 0.87, and the diode and photovoltaic parameters were also improved. At this condition, the doping concentration and junction depth were 7×10¹⁵cm^-3 and approximately 650 nm, respectively. The current collection efficiency in red light and longer wavelengths was improved in the sturdy junction. The efficiency of CdS/Cu(In,Ga)Se₂ solar cell was 13.4% when the composition of CIGS film was Cu_0.87 (In_0.66Ga_0.34)Se₂.

Keyword : solar cell, CIGS, Cu content, doping concentration, selenide source