Integration of Sb-based III-V materials grown directly onto Silicon by MBE

现代高性能光电器件已将III-V族半导体材料广泛纳入其结构中，特别是在技术上重要的近红外和中红外光谱范围附近工作时。这些材料由于其宽范围的可能的带隙、带偏移沿着高的电子和空穴迁移率而在许多领域引起了极大的兴趣。这些特性对探测器、光电子学和电信激光工业非常有用。就激光器而言，目前的技术已经达到了效率和带宽的极限，需要一种新的方法来满足不断增长的工业需求。然而，将III-V族材料直接集成到其他III-V族衬底（如InAs或GaSb）上并不是最有效的方法，这是由于可用的晶片尺寸小、成本高、导热性差和表面氧化层未优化。另一方面，集成到硅上在技术上具有挑战性，但对于任何设备的大规模生产和实施来说都是一个重要的发展。例如，GaSb和硅之间的大晶格失配（~13%）使得在没有以保护要在芯片上生长的器件的方式管理材料内部的内应力的技术的情况下，这种在硅晶片上的直接外延生长变得困难。这项工作的基础上，最近在兰开斯特开发的硅上的化合物半导体光电器件的实施的开创性工作，并导致了一个最低的报告线程缺陷密度的GaSb在Si上使用MBE。

Modern high-performance optoelectronic devices have widely incorporated III-V semiconductor materials into their structure, especially when operating near the technologically important near-IR and mid-IR spectral ranges. These materials have attracted great interest in many sectors due to their wide range of possible bandgaps, band offsets along with high electron and hole mobilities. Properties which are useful for detectors, photovoltaics and the telecoms laser industry. With respect to lasers, the current technology has hit the limit for efficiency and bandwidth and requires a new approach for growing industrial demands.However direct integration of III-V's onto other III-V substrates such as InAs or GaSb, is not the most effective approach due to the small wafer sizes available and their high cost, bad thermal conductivity and non-optimised surface oxide layers. Integration onto Silicon on the other hand is technologically challenging, but is an important development for large-scale production and implementation of any devices. The large lattice mismatch (~13%) between for example GaSb and Silicon makes this direct epitaxial growth onto Silicon wafers difficult without techniques to manage the internal stresses inside the material in a way that protects the device to be grown on the chip. This work builds upon the pioneering work on the implementation of compound semiconductor optoelectronic devices on Silicon recently developed at Lancaster, and has resulted in one of the lowest reported threading defect densities of GaSb on Si using MBE.