Growth of droplet-free InSbBi on GaAs substrate

Indium antimonide bismide (InSbBi) has emerged as a highly promising material for long-wavelength infrared photodetection devices due to its unique small energy bandgap (<0.17 eV) compared to existing III–V compound semiconductors. Despite its potential, experimental studies on InSbBi are still incomplete and scarce. Furthermore, the challenges associated with incorporating Bi and producing high-quality, defect-free samples are yet to be adequately addressed. To tackle these issues, we systematically investigated the growth of InSbBi on a GaAs substrate in this study. We incorporated up to 3.4% of Bi into InSbBi material. Our research contributes significantly to the field by demonstrating a technique for growing high-quality InSbBi material with Bi content of up to 2.3%, which is free of droplets and features a smooth surface. We achieved this goal by dynamically adjusting the Sb flux, carefully controlling the interplay between the Bi flux and the growth temperature, and implementing a post-growth annealing process. Our work is crucial for developing InSbBi technology as it contributes to the understanding of the growth process and surface morphology of InSbBi. Moreover, our results provide a path toward producing high-quality InSbBi samples.