Barrier рBn-Structure Based on GaAsSb/AlAsSb/InAsSb for Detection of IR Radiation in the Spectral Range of 3.1–4.2 µm

Abstract

In the study, a new рBn-architecture based on a GaAsSb/AlAsSb/InAsSb heterostructure of III-V group materials with an n-type AlAsSb barrier layer, an n-type InAsSb absorption layer, and a р-type GaAsSb collector layer, designed for detection of radiation in the mid-wavelength infrared range of 3.1-4.2 μm has been developed and investigated. The proposed structure has no valence band offset, which enables operation in a wide bias voltage range without depletion of the base n-type InAsSb active layer. The barrier in the conduction band, due to the presence of a wide-gap AlAsSb layer in the structure, is ∼1.0 eV, which is sufficient to eliminate the electron current component. The dark currents and performance of the рBn-structure have been analyzed, with the result that, at an operating temperature of Т ≈ 150 K and dark current density of J ≤ 6 × 10 -10 A/cm 2 , the detectivity value reaches D* ≥ 2.5 × 10 12 (cm W -1 Hz 1/2 ).