近年來將鍺整合於矽基板上製做成電子元件與光電元件已逐漸成為趨勢， 利用鍺的高吸收係數、高電子電洞遷移率以及窄能帶的優點；矽的高電離係數，易解離出新的電子電洞對可做為累增型光偵測器的增益層，且可整合在CMOS製程上。而矽鍺之間有著4.2%的晶格不匹配其整合上有一定的難度。一般將鍺磊晶在矽基板的方法主要是使用昂貴的高真空磊晶機台如分子束磊晶(MBE)、超高真空化學氣相沉積(UHVCVD)…等等，以上機台製程上都非常昂貴且成長速度慢。 本論文使用快速熱熔融磊晶成長法製作單晶鍺，較一般高真空機台更簡單快速且可降低成本。在SOI 基板上進行兩次快速熱熔融磊晶成長法，第一層為50nm的鍺緩衝層；第二層為500 nm 的鍺吸收層，第一層的緩衝層能夠侷限鍺矽介面所產生的差排且可作為第二層鍺的晶種點，成長為高品質的鍺吸收層，並利用TEM、SEM 及Raman 光譜進行材料分析。最後製做為分離式吸收、電荷、累增層之鍺矽光測器，並量測其光暗電流及光響應度。;Recently, silicon(Si)-based electronics integrated with germanium(Ge) are widely adopted due to the fact that Ge has a narrow band gap as absorption material for infrared wavelength and CMOS-compatible process, while Si has a favorable ionization coefficient ratio as avalanche multiplication material. However, it’s difficult to grow Ge on Si because of the large lattice mismatch (4.2%) between Si and Ge.Generally, epitaxial growth of Ge on Si relies on ultra-high vacuum chemical vapor deposition, which was expensive and time-consuming. In this report, we used rapid-melting-growth method to grown high-quality Ge on SOI (silicon-on-insulator), and then we can obtain a high-quality Ge absorption layer. Defect analysis was conducted by TEM, SEM and Raman Spectrometer.Furthermore, the SACM Ge/Si avalanche photodetector by rapid-melting-growth was fabricated and measured I-V characteristics of the fabricated device were studied.
