Doped InSb Detached Crystals by VDS Technique: Its Substrates for Infrared Devices and Physics Concept

Dattatray Gadkari

In this paper, the vertical directional solidification (VDS) detached crystal growth process in our laboratory in which a gap exists between a growing crystal and the ampoule wall is described. However, this phenomenon is more complex due to the hydrostatic pressure, and the existence of the buoyancy convections. Important characteristics of the detached growths are the self-stabilizing gas pressure difference and self-detachment crystal growth process into VDS on earth. The hydrostatic pressure decreases during the growth, the pressure at the bottom decreases such that the liquid meniscus remains unchanged all along the growth axis. Gap formation mechanism is not totally understood yet, but experimental observations can be seen that the gas passing upwards inside ampoules for grown ingots presence of the thin oxide layer. Detachment in VDS is self controlled and the self-applied pressure difference should be of the order of the hydrostatic pressure. In our references, characterization of high quality InSb and doped InSb substrates suitable for use in the infrared devices, and VDS technologies to deliver larger substrate is explained. Here, the physics behind detached growth and technology to develop the junction devices from these substrates is highlighted.