[19p-A404-1~19] 3.7 Laser processing

△ [19p-A404-8] Formation of GeSn Thin Films by Pulsed Laser Deposition

〇(B)Teppei Nakashima¹, Toshihumi Kikuchi^2,1, Kaname Imokawa^2,1, Daisuke Nakamura¹, Hiroshi Ikenoue^2,1 (1.ISEE, Kyushu Univ., 2.Dept. of Gigaphoton, Kyushu Univ)

Keywords:pulsed laser deposition, group IV materials, silicon-photonics

It is known that GeSn films, which is group Ⅳ materials, with substitutional Sn concentration above 8% has the direct-transition band-structures. Therefore, it is expected that GeSn films can be used as optical materials for silicon-photonics devices. However, the GeSn films with high substitutional Sn concentration is difficult to form, because thermal equilibrium solid-solubility of Sn in Ge is approximately 2 %.
We propose that high Sn concentration GeSn can be formed by pulsed laser deposition (PLD) with control of Ar partial pressure. In this presentation, we will introduce crystallinity and deposition mechanism of GeSn prepared by the PLD.