Atomic Mechanism of Interfacial-Controlled Quantum Efficiency and Charge Migration in InAs/GaSb Superlattice

Abstract

A series of systematic electron microscopy imaging evidence are illustrated to prove that a high-quality interface is vital for enhancing quantum efficiency from 23 to 50% effectively, because improved crystal quality of each layer can suppress the disordered atom arrangement and enhance the carrier lifetime via decreasing the overall residual strain. The distribution width of charge rises and then falls as bias increasing, revealing the existence of an optimum operating voltage, which could be attributed to the proper energy band bending. Our results provide new insights into the understanding of the association between macro-property and microstructure of the superlattice system.

Heterointerface‐Driven Band Alignment Engineering and its Impact on Macro‐Performance in Semiconductor Multilayer Nanostructures

“…III–V compound semiconductor family has been recognized as the next‐generation mainstream in the post‐Si era owing to their intrinsic advantages of direct bandgap and high electron mobility . With excellence in emitting and detecting light, they have broad application in laser diodes, infrared detectors, and light‐emitting diodes . For semiconductor devices, the interplay between microstructure, energy band and macro‐performance enables design flexibility.…”

“…For semiconductor devices, the interplay between microstructure, energy band and macro‐performance enables design flexibility. Through precise control on scale, shape, and composition, envelope wave function could be regulated through quantum confinement, achieving the tuning and tailoring of device performance . Such a method, nowadays known as band engineering, was originated by Esaki et al in 1970 .…”

“…The rapid advance on molecular beam epitaxy (MBE) in the 1980s further prospered the design‐to‐order methodology . Since then, semiconductor quantum confined structures, with diverse dimensionalities and band structures, have experienced a booming development, including quantum dots, nanowires, quantum wells (QW), and superlattices …”

“…Among all factors, with its inherent determination on actual band alignment, heterointerface is at the heart. It could be effectively regulated by strain, charge, distortion, and defect, which alter macro‐performance and even induce an emergent phenomenon . For instance, in AlGaAs/GaAs heterostructures, nearly impurity‐free interfaces could be formed with a concerted growth sequence, achieving electron mobility as unprecedentedly high as >35 million cm 2 V −1 s −1 .…”

“…From another perspective, due to its decisive influence on the distribution and aggregation of charges, band alignment is frequently exploited to regulate macro‐performance by modulating microstructures . For example, insertion of ZnGeN 2 into InGaN/GaN transforms the initial type‐Ⅰ band alignment into type‐Ⅱ, enhancing the wave function overlap to boost spontaneous emission rate .…”