[16a-D511-1~10] 15.5 Group IV crystals and alloys

▲ [16a-D511-3] Optical properties of highly strained n-Ge films grown by CW laser annealing

〇Rahmat Hadi Saputro^1,2, Ryo Matsumura¹, Tatsuro Maeda³, Naoki Fukata^1,2 (1.NIMS, 2.Univ. of Tsukuba, 3.AIST)

Keywords:Germanium, Strain, Photoluminescence

Recently, germanium (Ge) is considered as a promising material for optoelectronic devices integration. Even though Ge is an indirect-band semiconductor like Silicon (Si), the small gap (0.136 eV) between direct and indirect-band can be reduced by introducing tensile strain. Furthermore, it was reported that in 0.2-0.3% tensile strained Ge, n-type doping in the order of 10¹⁹ cm^-3 shows quasi direct-band emission behavior. We have successfully grown 0.55-0.62% tensile strained Ge on quartz substrate by continuous wave laser annealing (CWLA). In this study, we applied the CWLA for the Sb-doped n-type Ge film and characterize the band structure in relation to its tensile strain.