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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]

In this study, we have designed, fabricated, characterized, and analyzed plasma-enhanced chemical vapor deposition (PECVD) diamond-based Schottky diodes for high power electronics applications. We have elaborated four critical issues in the synthetic-diamond semiconductor technology: 1) growth, 2) doping, 3) Schottky contact, and 4) different device structures in order to achieve better performance parameters. We have obtained 500 V of breakdown voltage on one device and 100 A/[cm.sup.2] of current density on another device, optimized for different applications. These values are among the highest reported with the polycrystalline diamond-based devices. We have utilized different fabrication techniques for the growth of PECVD-diamond, different metals as a Shottky contact on diamond film and also optimized structural parameters such as diamond film thickness and doping concentration in order to achieve a high-performance power diodes. Analysis of the current conduction mechanisms of these devices in this study revealed a space-charge-limited current conduction mechanism in the forward bias region while thermionic field emission controlled current conduction mechanism in the reverse bias region. Performance parameters such as forward voltage drop, barrier height, and current density were analyzed as a function of temperature and type of metal Schottky contacts. Index Terms--Diamond, diode, power, Schottky.