Conference paper

Publication year: 1999

Pages: 930-933

Journal: Physica B: Condensed Matter

Volume number: 273-4

ISSN: 0921-4526

eISSN: 1873-2135

DOI Link: https://doi.org/10.1016/S0921-4526(99)00557-8

Conference: 20th International Conference on Defects in Semiconductors (ICDS-20)

Publisher: Elsevier

Abstract: 
Thin(similar to 1 mu m) CuIn(Ga)Se-2 layers were grown by the rapid thermal processing technique under In-rich conditions. The as-grown samples were slightly p-type but highly compensated. They showed strong positron trapping in vacancies, indicated by a large valence annihilation parameter S. In order to identify the vacancies, we applied a novel PAS-method. In that, we compare the element-specific high-momentum part of the annihilation momentum distribution f(p) in CuInSe2 with f(p) from the pure elements constituting the material (i.e. with Cu, In and Se). The results provide direct evidence that the vacancies in our as-grown CuInSe2 layers are related to Cu vacancies. Annealing under Ar atmosphere did not alter the annihilation characteristics, i.e. it did not affect the vacancies. However, after annealing in air the samples become more heavily p-type and less compensated, whereas S is drastically reduced. PAS measurements as a function of temperature revealed that this effect is not due to a reduction of the vacancy concentration but due to the additional presence of negatively charged ions introduced by the annealing process. According to recent results, these ions are attributed to oxygen accepters O-Se. These new accepters account for the increase of p-type conductivity after air annealing. (C) 1999 Elsevier Science B.V. All rights reserved.

Harvard Citation style: Börner, F., Gebauer, J., Eichler, S., Krause-Rehberg, R., Dirnstorfer, I., Meyer, B., et al. (1999) Defects in CuIn(Ga)Se₂ solar cell material characterized by positron annihilation:: post-growth annealing effects, Physica B: Condensed Matter, 273-4, pp. 930-933. https://doi.org/10.1016/S0921-4526(99)00557-8

APA Citation style: Börner, F., Gebauer, J., Eichler, S., Krause-Rehberg, R., Dirnstorfer, I., Meyer, B., & Karg, F. (1999). Defects in CuIn(Ga)Se₂ solar cell material characterized by positron annihilation:: post-growth annealing effects. Physica B: Condensed Matter. 273-4, 930-933. https://doi.org/10.1016/S0921-4526(99)00557-8