Epitaxy of Ge Layers on Blanket and Patterned Si(001) for Nanoelectronics and Optoelectronics

Growth and Characterization of SiGe/SiO2 Core/Shell Nanocrystals on Insulators

“…Silicon–germanium alloy (Si 1– x Ge x ) is emerging as a crucial material for future advances in silicon-based devices. This composite presents a preparation technique that is fully compatible with existing silicon technology, paving the way to various applications. − Notably, it is recommended as a substitute for silicon in several applications in nanoelectronics and photonics due to several properties, such as the low melting temperature of germanium compared to silicon, as well as favorable physical properties at lower temperatures than those required for silicon. − The ability to process the Si 1– x Ge x alloy at lower temperatures is of particular importance, aligning with the current trend in submicrometer integrated circuit device fabrication, where high temperatures are increasingly less compatible. In addition, Si 1– x Ge x alloy crystals offer a new degree of freedom to optimize their optoelectronic properties by modifying the relative proportions of silicon and germanium. − Si 1– x Ge x alloy nanocrystals present a unique opportunity to control the band gap energy by tuning the germanium content .…”

An FDTD Investigation of Compact and Low-Voltage Waveguide-Integrated Plasmonic Ge/SiGe Multiple Quantum Wells Photodetectors

“…Nevertheless, as the structures of Ge/SiGe MQWs also contain SiGe barriers, compared to bulk Ge waveguide photodetectors, Ge/SiGe MQWs waveguide photodetectors will generally have less Ge absorbing layers, which contributes to the longer device length required to obtain competitive detection performance [8]. Moreover, contrary to the case of Ge on Si in which high quality Ge can be grown directly on Si thanks to annealing techniques [23][24][25], a Ge-rich SiGe relaxed buffer is usually required to grow Ge/SiGe MQWs on Si [7,26,27], and the presence of additional buffer layers further reduces the optical overlap between the guided optical mode and the absorbing Ge/SiGe MQWs region [12,21,22]. As a result, at present the reported Ge/SiGe MQWs waveguide photodetector still require at least 80-100 µm absorption length in order to attain comparable detection performance to that of state-of-the-art bulk Ge waveguide photodetectors with almost five times shorter absorption length of ~ 10-20 µm, at similar values of intrinsic region thickness and bias voltage.…”