2020-03-012024-05-16https://scholars.lib.ntu.edu.tw/handle/123456789/667035摘要：11<br> Abstract: While marketing for the 5G communications have been just started, the pursuing for the infrastructures, both in hardware and software, of 6th genesis (6G) that integrate satellite communication and serving as the bridge for separate 5G networks, has come into the focus of the major research branches. This range of operation require device with super-fast operation speed, ultra-low bandgap, high stability, and of course, cost effective and mass-production enable. To support the comprehensive coverage of the next generation communications, two of the directions come into focus: ultra-low bandgap materials and perovskite. 　The development of ultra-low bandgap materials, aiming for the spectrum area (4~8μm), with wavelength large enough to cover the satellite communications. So far, the pursuing of ultra-low band materials is limited by the capabilities of reliably shrinking bandgap of the semiconductor materials. Among all the applicable candidate, GeSn is the best candidate whose bandgap are controlled by the Sn concentration, and direct bandgap for Sn >12%, and is compatible, cheap, and MOCVD applicable for large amount reparation. However, the GeSn becomes vulnerable to temperature as the Sn concentration reach higher than 21% inside the lattice structures, which currently cap the bandgap of GeSn to only 0.3eV (~4μm). This restrains the capabilities of using GeSn as the emitter, receiver, detector, and even the THz transistors in 6G regime. Thus, the pursuing of GeSn with high Sn concentration becomes the limit factor in designing the hardware in the next generation satellite communications. Moreover, the defective growth buffer layer, as shown in Fig. 1, used in the GeSn epitaxial deposition are built in the GeSn applications that significantly reduce the optical properties due to the trap-assisted recombination within this region. This also made the GeSn based laser still under development. In this proposal, we will focus on the release of GeSn from its growth substrate and apply the mature nanomembranes printing-transfer techniques to print the GeSn nanomembranes back to designate substrate. Upon the release of the GeSn film, we can apply the selective wet-etching process to remove the defective layer happened during the growth approaches. In this way, we can engineer and maintain the top GeSn nanomembrane with its superior material properties. Meanwhile, the excessive and external strain engineering can be applied to the release membrane to elevate the valley of the lightly holes to further shrinking the material properties.鈣鈦礦鍺化錫奈米薄膜轉置衛星通訊PerovskiteGeSnNanomembranePrintingSatellite communication