Affiliation of Author(s):材料科学与技术学院

Journal:JOURNAL OF ALLOYS AND COMPOUNDS

Key Words:Cu(InGa)Se-2 thin film Cu(InGa)Se-2 solar cell CaF2 post-deposition treatment CdS/Cu(InGa)Se-2 interface

Abstract:It is considered that alkaline elements (such as Na, K, Rb) introduced through post-deposition treatment are able to modify the near-surface region of Cu(InGa)Se-2 thin films. However, research on the effects of Ca element on properties of Cu(InGa)Se-2 thin films is hardly reported. In this paper, Cu(InGa)Se-2 thin films were prepared on quartz glass by e-beam evaporation via two-step process. Study of structural property showed that a certain amount of CaF2 through post-deposition treatment was beneficial to the uniform composition distribution of Cu(InGa)Se-2 thin films. Near-surface region of Cu(InGa)Se-2 thin films was more Cu-depleted by increasing introduced amount of Ca element. It was inferred that Ca diffused into the Cu(InGa)Se-2 thin films substituted the In sites as Ca-In so as to increase the carrier concentration. By calculation, the spike barrier of CdS/Cu(InGa)Se-2 heterojunction was shown to decrease with increased thickness of CaF2 layers. As a result, Cu(InGa)Se-2 solar cell subjected to 20 nm CaF2 postdeposition treatment, which possessed higher fill factor, open circuit voltage and short circuit current density, achieved the optimal power conversion efficiency. An efficiency of Cu(InGa)Se-2 solar cell was enhanced by 2.9% after 20 nm CaF2 post-deposition treatment. (c) 2018 Elsevier B.V. All rights reserved.

ISSN No.:0925-8388

Translation or Not:no

Date of Publication:2018-10-25

Co-author:陈洁仪,翟子豪,Lily,衣云鸽,林宇星,于闯,顾泽钰

Correspondence Author:shl