Since its bandgap is close to optimum value, AgGaTe2 is regarded as a promising material for solar cells. This paper reports the result of photoluminescence (PL) experiments on AgGaTe2 thin films prepared by the two-step closed space sublimation method. In particular, the effect of by-products including Ag2Te or AgGa5Te8 on PL properties of AgGaTe2 is investigated. The radiative recombination process is also explored. PL measurements of thin films are performed by changing the excitation intensity and measured temperature. It is confirmed that the emission band probably derived from defects and impurities exists near 1.02 eV and the emission band derived from free exciton (FE) exists around 1.32 eV, and the variation of FE emission intensity is affected by the Ag/Ga ratio in AgGaTe2. It is also investigated that the activation energy (EA) of the FE emission is about 7.8 meV.
|ジャーナル||Physica Status Solidi (A) Applications and Materials Science|
|出版ステータス||Published - 2019 1月 9|
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