[10a-PB3-1~14] 13.9 Compound solar cells

△ [10a-PB3-3] Optical Properties of Cr doped CuGaS₂ Thin Films

〇(M1)Myeongok Kim¹, Nazmul Ahsan², Hiroya Matsubayashi³, Zacharie Li Kao Jehl², Kalainathan Sivaperuman⁴, Yoshitaka Okada^2,3 (1.Grad. Arts and Sci. UTokyo, 2.RCAST. UTokyo, 3.Elec. Eng. UTokyo, 4.VIT Univ.)

Keywords:Chalcopyrite, Intermediate band, RF magnetron sputtering deposition

CuGaS₂ (CGS) has been researched for various applications, such as laser or artificial photosynthesis. For CGS has a wide band gap and CGS intermediate band solar cells (IBSCs) are expected to have a theoretical efficiency of 47%, this research investigated the optical properties of Cr doped CGS for its potential application in IBSCs. Photoluminescence (PL) and absorption spectra measurements were conducted on samples made by RF magnetron sputtering. For compositional analysis, energy dispersive X-ray spectrometry (EDX) was measured.
It is found from absorption spectra measurement that Cr doping causes red shift of band edge. This may be due to the formation of intermediate band. From PL measurement, peak intensity has increased by Cr doping. Increased intensity may attribute to reduction in defects due to Cr doping. Since current research has investigated PL in short wavelength region, future work will be conducted on longer wavelength region for intermediate band analysis.