Passivation of InSb photodetectors with atomic layer deposited Al2O3

Abstract

The preparation of surface passivation layers on InSb is essential in the process of device fabrication. An Al2O3 passivation film was deposited on the surface of medium wave InSb film by atomic layer deposition (ALD). A series of variable area photodiode devices with different P/A ratios were fabricated. The performance of the device is characterized at 77K. The effects of ALD Al2O3 and anodic oxidation on the leakage current of diode devices were investigated. The surface leakage current of the passivated photodetectors was reduced by an order of magnitude over the anode sulfidation passivated photodetectors. Moreover, the metal-insulator-semiconductor (MIS) device were developed respectively, and the effects of different films as a dielectric layer on the interfacial characteristics were investigated.

High-Affinity Ligand-Enhanced Passivation of Group III–V Colloidal Quantum Dots for Sensitive Near-Infrared Photodetection

“…Infrared (IR) photodetectors are widely used in bioimaging, machine vision, augmented reality, and autonomous driving. , Colloidal quantum dots (CQDs) are promising next-generation IR-absorbing materials that can overcome the limitations of conventional materials that require high-quality single-crystalline substrates and high-temperature vacuum processing for epitaxial growth, such as InGaAs, InSb, and Hg 1– x Cd x Te. − The solution processability of CQDs enables low-cost mass production of large-area specimens regardless of the substrate materials. − Additionally, the optoelectronic properties of CQDs can be readily fine-tuned by adjusting their size, shape, and surface chemistry. Particularly, PbS-CQD-based IR photodetectors have been studied extensively in recent years because PbS CQDs exhibit high bandgap tunability from visible to short-wavelength IR regions and a high intrinsic absorption coefficient (>10 4 cm –1 ) in the IR region.…”