[26a-E301-1~9] 3.13 Semiconductor optical devices

▲ [26a-E301-7] Formation of Ge_1−xSn_x/Si_xGe_1−x−ySn_y double quantum wells structure and its photoluminescence mechanism

〇Shiyu Zhang¹, Shigehisa Shibayama¹, Osamu Nakatsuka^1,2 (1.Nagoya Univ., 2.IMaSS, Nagoya Univ.)

Keywords:GeSn, quantum well, photoluminescence

Replacing metallic interconnect by optical interconnect has been considered as a powerful method to reduce power dissipation in the future Si LSI technology. Ge_1-xSn_x is one of the important candidates to realize a light source for optical interconnect as it has a potential of direct transition energy bandgap and a good affinity with Si LSI platform. Our group has previously reported the epitaxial growth of Ge_1−xSn_x/Si_xGe_1−x−ySn_y and n⁺-Ge_1−xSn_x/n-Si_yGe_1−y single-quantum well (QW) structure and demonstrated the enhancement of the photoluminescence (PL) intensity by specific heterostructure designs.
In this study, to further increase PL performance, we achieved the epitaxial growth of a double quantum wells (QWs) Ge_1−xSn_x/Si_xGe_1−x−ySn_y structure and found that its PL intensity was improved at low temperature compared to the single-QW structure. This mechanism will be discussed from the perspective of energy band alignment, wave function extensions, and overlaps to give a better understanding of the PL property of group-IV semiconductor quantum well structures.