The 67th JSAP Spring Meeting 2020

Presentation information

Poster presentation

13 Semiconductors » 13.9 Compound solar cells

[14a-PA5-1~23] 13.9 Compound solar cells

Sat. Mar 14, 2020 9:30 AM - 11:30 AM PA5 (PA)

9:30 AM - 11:30 AM

[14a-PA5-19] Controlling Optical Properties of Sputtered CuGaS2 by Sulfurization

〇(M2)Myeongok Kim1, Nazmul Ahsan2, Nanaki Miura3, Zacharie Jehl4, Yoshitaka Okada2,3 (1.Grad. Arts and Sci. UTokyo, 2.RCAST UTokyo, 3.Elec. Eng. UTokyo, 4.IREC)

Keywords:CuGaS2, Sputtering, Posts sulfurization

For its high absorption coefficient and wide band-gap, CuGaS2 (CGS) is a promising material for optical devices. However, due to challenges in making CGS thin films with high crystallinity, there is few previous study on CGS device performance. This research, therefore, investigated the effect of sulfurization on optical properties of sputtered CGS expecting sulfurization improves quality of the film.
CGS thin films were sputtered using stoichiometric CGS target at 200oC. The samples were annealed at 550oC with sulfur powder under N2 gas atmosphere. PL measurement were conducted at room temperature using 405nm laser. PL signals at 2.46eV, which correspond to the band-edge of CGS, were measured. There were other signals around 1.5eV from deep defective state, but the intensity could be suppressed by controlling sulfurization condition. Further studies on material properties are crucial for understanding the mechanism of defect suppression by sulfurization and further improving the optical properties of CGS.