Laryn, Tsimafei Chu, Rafael Jumar Kim, Yeonhwa Madarang, May Angelu Lung, Quang Nhat Dang Ahn, Dae-Hwan Han, Jae-Hoon Choi, Won Jun Jung, Daehwan 2024-06-13T02:30:11Z 2024-06-13T02:30:11Z 2024-06-13 2024-06 1944-8244 https://pubs.kist.re.kr/handle/201004/150068 Monolithic integration of III-V quantum dot (QD) lasers onto a Si substrate is a scalable and reliable approach for obtaining highly efficient light sources for Si photonics. Recently, a combination of optimized GaAs buffers and QD gain materials resulted in monolithically integrated butt-coupled lasers on Si. However, the use of thick GaAs buffers up to 3 mu m not only hinders accurate vertical alignment to the Si optical waveguide but also imposes considerable growth costs and time constraints. Here, for the first time, we demonstrate InAs QD lasers epitaxially grown on a 700 nm thick GaAs/Si template, which is approximately four times thinner than the conventional III-V buffers on Si. The optimized 700 nm GaAs buffer yields a remarkably smooth surface and low threading dislocation density of 4 x 10(8) cm(-2), which is sufficient for QD laser growth. The InAs QD lasers fabricated on these ultrathin templates still lase at room temperature with a threshold current density of 661 A/cm(2) and a characteristic temperature of 50 K. We believe that these results are important for the monolithically integrated III-V QD lasers for Si photonics applications. English American Chemical Society Reduction of GaAs Buffer Thickness and Its Impact on Epitaxially Integrated III-V Quantum Dot Lasers on a Si Substrate Article 10.1021/acsami.4c04597 1 ACS Applied Materials & Interfaces, v.16, no.23, pp.30209 - 30217 ACS Applied Materials & Interfaces 16 23 30209 30217 N scie scopus 001238283400001 Nanoscience & Nanotechnology Materials Science, Multidisciplinary Science & Technology - Other Topics Materials Science Article TEMPERATURE GROWTH quantum dot epitaxy silicon photonics quantum dot laser photoluminescence defect