Investigation of the role of Threading Dislocation Density on Interband Cascade LEDs grown on Silicon substrates via Molecular Beam Epitaxy

In this work we examine the impact of Threading Dislocation Density (TDD) on the performance of ICLEDs grown on GaSb-on-Si buffers and techniques for reducing the TDD. Antimonides have shown to be a useful platform for integrating optoelectronic devices on Silicon substrates. The buffer in this study consists of an AlSb layer to assist with nucleation on Silicon substrates and a thick GaSb buffer. Interband cascade LED structures grown on this buffer design have exhibited comparable performance compared to the native III-V substrate, but there is room for improvement in buffer quality and consistency in device performance. The threading dislocations in these devices are characterized and quantified using cross-sectional Transmission Electron Microscopy (XTEM) and X-Ray Diffraction reciprocal space mapping (RSM). The ICLED performance is demonstrated through electrical and optical characterization.