Defect level signatures in CuInSe2 by photocurrent and capacitance spectroscopy

• Published in: Thin solid films 2013-05, Vol.535, p.366-370
• Main Authors: Krysztopa, A., Igalson, M., Gütay, L., Larsen, J.K., Aida, Y.
• Format: Article
• Language: English
• Subjects: Applied sciences; Capacitance spectroscopy; CIGSe; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Defect levels; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Electronic transport phenomena in thin films and low-dimensional structures; Energy; Exact sciences and technology; Meyer–Neldel; Natural energy; Photoconduction and photovoltaic effects; photodielectric effects; Photovoltaic conversion; Physics; PICTS; Solar cells; Solar cells. Photoelectrochemical cells; Solar energy; Surface and interface electron states; Surface states, band structure, electron density of states
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2012.12.084

Results of defect levels spectroscopy on epitaxial and polycrystalline CuInSe2 by photocurrent and capacitance methods are presented. Electronic parameters of defect levels found by photocurrent methods are compared with those obtained through the use of capacitance spectroscopy on CuInSe2 solar cells. In the discussion, we include the Meyer–Neldel plot as a method of differentiation between the levels in the case of parameter variation between samples and depending on measurement conditions. The levels common for all compounds from the Cu(In,Ga)Se2 family are specified. The origin of the N1 and N2 defect levels frequently observed in the capacitance spectra of solar cells is discussed and the coincidence of the N2 level and the E4 bulk level is shown. ► Parameters of seven defect levels in CuInSe2 are collected. ► Some that are observed in CuGaSe2 defects are confirmed in CuInSe2. ► Candidate for recombination center is observed in CuInSe2 and CuGaSe2. ► First database of defect levels in CuInSe2 is created.