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The quantum efficiency of an InAs/InAsSb type-II superlattice (T2SL) high operating temperature (HOT) long-wavelength infrared (LWIR) photodetector may be significantly improved by integrating a two-dimensional subwavelength hole array in a metallic film (2DSHA) with the detector heterostructure. The role of the metallic grating is to couple incident radiation into surface plasmon polariton (SPP) modes whose field overlaps the absorber region. Plasmon-enhanced infrared photodetectors have been recently demonstrated and are the subject of intensive research. Optical modelling of the three-dimensional detector structure with subwavelength metallic components is challenging, especially since its operation depends on evanescent wave coupling. Our modelling approach combines the 3D finite-difference time-domain method (FDTD) and the rigorous coupled wave analysis (RCWA) with a proposed adaptive data-point selection for calculation time reduction. We demonstrate that the 2DSHA-based detector supports SPPs in the Sommerfeld-Zenneck regime and waveguide modes that both enhance absorption in the active layer. [ABSTRACT FROM AUTHOR]

This paper presents a behavioral model for a Si/Si1−xGex multi-quantum well (MQW) detector that predicts device characteristics to investigate the effect of increasing Ge content in Si/Si1−xGex MQW. The modeling approach in this paper is based on a physical instead of empirical approach, which allows to obtain a predictive behavioral analysis of high Ge content with only a few fitting parameters. The model is used to simulate device transfer characteristics with respect to various amounts of Ge content used for Si1−xGex layer in MQW. The simulation results of the proposed model are validated with the experimental data. The simulated and the experimental data are consistent over a wide range of Ge content varied from 30% up to 50%. The primary objective of this paper is to optimize Ge content in the Si/Si1−xGex MQW detector to achieve desired thermal sensitivity measured in terms of temperature coefficient of resistance for a potential microbolometer application. This is the first study in the literature to develop such a highly predictive behavioral model of a Ge-enriched Si/Si1−xGex MQW. The study also presents the effect of including the carbon delta layers at the Si/Si1−xGex heterointerface on the device transfer characteristics. The effect of Ge content on the overall noise is also investigated by the noise characterization of the test devices. [ABSTRACT FROM AUTHOR]

This paper presents a predictive device model implemented by a self-consistent solution of Poisson–Schrödinger drift-diffusion formulation for a thermally sensitive detector based on a ${\mathrm {Si/Si}}_{{1}-{x}}{\mathrm {Ge}}_{{x}}$ multiquantum-well structure. The physical phenomena governing the carrier transport were modeled to investigate the effect of physical design aspects (Ge content, well periodicity, and well thickness). In particular, we have analyzed the effect of these physical design parameters on the carrier dynamics quantified by the dc performance in terms of net current density. A fully integrated simulation framework was developed and employed to optimize Ge content and device doping for a desired figure of merits specified by temperature coefficient of resistance (TCR) and dc resistance (${R}$). This methodology was successfully utilized to realize device profiles for various amounts of Ge content and optimization of (${R}$) geared for both high TCR and low noise. The dc performance metrics of the optimized profiles obtained by modeling presented here are compared and validated with the fabricated test devices. [ABSTRACT FROM AUTHOR]