Polarization modulation in GaN-based double-barrier resonant tunneling diodes

Abstract

The effect of polarization modulation on GaN-based double-barrier resonant tunneling diodes is theoretically investigated. The polarization field is shown to improve the performance of these devices by increasing the peak current, peak-to-valley ratio, and negative differential conductance. The high sensitivity of the quantum-well bound energy state with the applied bias explains the observed characteristics. We have further demonstrated that a thin In0.1Ga0.9N layer can significantly improve the performance of the devices by introducing an additional polarization field beyond the second barrier, which reduces the device series resistance and increases the effective second barrier height and width.

A Restrain Method of Polarization Effect in GaN/AlGaN RTD

“…The proposed GaN/AlGaN RTDs are featured of the same order current as the result in [10], [12] and [15] at much lower peak and valley voltages. Moreover, the peak and valley currents and all feature voltages increase nonlinearly with  as illustrated in Figure IV }, which is enough to satisfy the PVCR requirement for low voltage and low power loss MVL and supercomputer design applications.…”

“…As a result, the GaN/AlGaN RTD with the crystal plane { 1 0 2 2 } as the initial crystal plane of substrate commence to appear practical NDR characteristic for low voltage and low power loss MVL application, which might be approximately defined as critical RT crystal plane. Even the NDR characteristic of a-plane RTD is observed at less than half peak and valley voltages of the result in [10], [12] and [15]. Besides, the GaN/AlGaN RTD with the crystal plane { 1 0 8 8 } as the initial crystal plane of substrate appears the maximum PVCR at about 34.09.…”

“…They are the optional materials for high frequency devices, high power devices, optoelectronic devices [1][2][3][4][5][6][7][8][9][10][11]. The main reason for this originates from their direct band gap tunable along a wide range of energies and that they appear higher electron mobility, thermal conductivity and wider band gap than silicon counterparts.…”

“…The main reason for this originates from their direct band gap tunable along a wide range of energies and that they appear higher electron mobility, thermal conductivity and wider band gap than silicon counterparts. With the development of III-Nitrides materials and devices, more and more attention are paid to the studies on GaN/AlGaN-based RTD (resonate tunneling diode) [7][8][9][10]12]. Resonant tunneling diodes (RTDs) which display a Negative Differential Resistance (NDR) are exploited in digital applications (Multi-Value Logic) as well as in analog applications (ADC, frequency divider or multiplier, oscillator), leading to simpler circuits, with a large gain in low power consumption and high frequency performance [7,8,10,12,13].…”

A novel quantum well RTD with intensive and continuous current oscillation in the bias voltage range higher than 3.15 V

“…signifies the charge increment in the i th layer at given bias voltage than in thermal equilibrium, i  signifies the pure polarization sheet charge density at i th interface and each can be calculated precisely and respectively as 1.4075e13 q/cm -2 , -5.4686e12 q/cm -2 , 1.3102e13 q/cm -2 and -7.4010e12 q/cm -2 by combining the nonlinear polarization model and Vegard's low according to the references [5,7,8].…”