Analysis and Performance Study of III–V Schottky Barrier Double-Gate MOSFETs Using a 2-D Analytical Model

The optimization of high power terahertz monolithic integrated circuit (TMIC) is systemically studied based on the physical model of the Schottky barrier varactor (SBV) with interface defects and tunneling effect. An ultra-thin dielectric layer is added to describe the extra tunneling effect and the damping of thermionic emission current induced by the interface defects. Power consumption of the dielectric layer results in the decrease of capacitance modulation ration (C max/C min), and thus leads to poor nonlinear C–V characteristics. The proposed Schottky metal-brim (SMB) terminal structure could improve the capacitance modulation ration by reducing the influence of the interface charge and eliminating the fringing capacitance effect. Finally, a 215 GHz tripler TMIC is fabricated based on the SMB terminal structure. The output power is above 5 mW at 210–218 GHz and the maximum could exceed 10 mW at 216 GHz, which could be widely used in terahertz imaging, radiometers, and so on. This paper also provides theoretical support for the SMB structure to optimize the TMIC performance.

Section: Description Of the Simulation Processmentioning

confidence: 99%

Optimization of terahertz monolithic integrated frequency multiplier based on trap-assisted physics model of THz Schottky barrier varactor

Qi¹,

Jin²,

Liu³

et al. 2020

“…The electrical simulations described in this paper are performed using Sentaurus TCAD tools. [11] The simulations with metal-interfacial layer-semiconductor (MIS) model which is shown in Fig. 3 are based on the literature in Refs.…”

Section: Fabrication and Simulationmentioning

confidence: 99%

Improvements in reverse breakdown characteristics of THz GaAs Schottky barrier varactor based on metal-brim structure

Liu

Jin

et al. 2020

The excellent reverse breakdown characteristics of Schottky barrier varactor (SBV) are crucially required for the application of high power and high efficiency multipliers. The SBV with a novel Schottky structure named metal–brim is fabricated and systemically evaluated. Compared with normal structure, the reverse breakdown voltage of the new type SBV improves from –7.31 V to –8.75 V. The simulation of the Schottky metal–brim SBV is also proposed. Three factors, namely distribution of leakage current, the electric field, and the area of space charge region are mostly concerned to explain the physical mechanism. Schottky metal–brim structure is a promising approach to improve the reverse breakdown voltage and reduce leakage current by eliminating the accumulation of charge at Schottky electrode edge.

“…The electrical simulations of the metal-interfacesemiconductor (MIS) model [22] which is described in this paper are performed using the Sentaurus TCAD tool. [23] The model is based on the basic drift-diffusion and Poisson equations for direct current (DC), breakdown characteristics, and small-signal simulation. This basic drift-diffusion model includes the Fermi statistics, mobility with doping dependence and high-velocity saturation model, carrier generation, recombination, non-local tunneling, and band to band tunneling.…”

Section: Introductionmentioning

confidence: 99%

High frequency doubling efficiency THz GaAs Schottky barrier diode based on inverted trapezoidal epitaxial cross-section structure

Liu¹,

Zhang²,

Wang³

et al. 2023

A high-performance terahertz Schottky Barrier Diode (SBD) with an inverted trapezoidal epitaxial cross-section structure featuring high varactor characteristics and reverse breakdown characteristics is reported in this paper. Inductively coupled plasma dry etching and dissolution wet etching are used to define the profile of the epitaxial layer, by which the voltage-dependent variation trend of the thickness of the metal-semiconductor contact depletion layer is modified. The simulation of the inverted trapezoidal epitaxial cross-section SBD is also proposed, to explain the physical mechanism of electric field and space charge region area. Compared with the normal structure, the grading coefficient M increased from 0.47 to 0.52, and the capacitance modulation ratio (C max/C min) increased from 6.70 to 7.61. Inverted trapezoidal epitaxial cross-section structure is a promising approach to improve the Variable-capacity ratio by eliminating the accumulation of charge at the Schottky electrode edge. A 190 GHz frequency doubler based on inverted trapezoidal epitaxial cross-section SBD also shows a doubling efficiency of 35% compared to a normal SBD of 30%.