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In this paper, systematic characterization and the corresponding suppression strategies of dynamic OFF-state leakage current (${I}_{ \mathrm{\scriptscriptstyle OFF}}$) in Schottky-type p-GaN gate high-electron-mobility transistors (HEMTs) are presented based on fast pulsed ${I}$ – ${V}$ measurement and consecutive switching measurement. It is found that the high ${I}_{ \mathrm{\scriptscriptstyle OFF}}$ under dynamic pulse mode without hole injection is a result of the reduced voltage blocking capabilities (both lateral and vertical) with weaker trapping effect in the buffer, and the dynamic ${I}_{ \mathrm{\scriptscriptstyle OFF}}$ induced by ON-state hole injection is caused by further increased lateral conductivity through the buffer from source to drain. The corresponding behaviors under continuous waveforms with different switching conditions are analyzed to identify effective approaches for the suppression of dynamic ${I}_{ \mathrm{\scriptscriptstyle OFF}}$ in practical switching operations. A higher temperature is shown to be beneficial to the reduction of the dynamic ${I}_{ \mathrm{\scriptscriptstyle OFF}}$ induced by ON-state hole injection. To completely eliminate the dynamic ${I}_{ \mathrm{\scriptscriptstyle OFF}}$ caused by ON-state hole injection and minimize the OFF-state power consumption in practical power switching applications, a sufficiently large negative OFF-state gate bias (e.g., ${V}_{\text {GS}, \mathrm{\scriptscriptstyle OFF}}\le -{3}$ V) is recommended in the gate driver turn-off voltage design for the Schottky-type p-GaN gate HEMTs. [ABSTRACT FROM AUTHOR]

A p-type shield region (p-shield) under the gate trench is typically adopted in a SiC trench MOSFET for achieving a lower oxide field and reverse transfer capacitance ( Crss) . This paper comparatively studies the effects of a grounded p-shield and a floating p-shield. Device simulations using Sentaurus TCAD are carried out in this paper to reveal the devices’ internal dynamics. The floating p-shield can effectively reduce the OFF-state oxide field as a grounded p-shield does, without degrading its static performance. However, after being switched from the OFF-state, the ON-state oxide field in the trench MOSFET with a floating p-shield (FS-MOS) is dramatically elevated. Compared with the trench MOSFET with a grounded p-shield, the FS-MOS also exhibits a higher C{{\text {rss}}} and a consequently slower switching speed. Furthermore, the FS-MOS exhibits a degradation of dynamic R{ \mathrm{ON}} during switching operation. A charge storage mechanism is then presented to explain the dynamics in FS-MOS. Upon a high V{{\text {DS}}} , holes are emitted from the floating p-shield when the parasitic p-n-p structure consisting of p-shield, p-body, and n-region between them is punched through, leaving negative charges in the floating p-shield even when the high V{{\text {DS}}} is removed. Based on this mechanism, the behaviors of the FS-MOS are well explained. [ABSTRACT FROM AUTHOR]

In this paper, we present a comprehensive reviewand discussion of the state-of-the-art device technology and application development of GaN-on-Si power electronics. Several device technologies for realizing normally off operation that is highly desirable for power switching applications are presented. In addition, the examples of circuit applications that can greatly benefit from the superior performance of GaN power devices are demonstrated. Comparisonwith other competingpower device technology, such as Si superjunction-MOSFET and SiC MOSFET, is also presented and analyzed. Critical issues for commercialization of GaN-on-Si power devices are discussed with regard to cost, reliability, and ease of use. [ABSTRACT FROM AUTHOR]

In this paper, static and dynamic performances of an AlGaN/GaN-on-Si power FET utilizing the integrated photonic-ohmic drain (PODFET) were systematically investigated. The operational mechanisms of the PODFET, including both the conditions of photon generation and the related physical processes, were explained. The dynamic switching tests were carried out under two types of hard switching conditions. With the photon generation and channel current inherently switched ON and OFF in synchronization, the dynamic performances of the PODFET can be significantly enhanced owing to photon pumping of deep electron traps. In addition, the generated photons were proved to be confined in proximity of the drain terminal without causing adverse effects on the device performances (e.g., the OFF-state leakage degradation). [ABSTRACT FROM PUBLISHER]

We investigate in detail the influence of AlN passivation on dynamic ON-resistance ( \(R_{\mathrm{{\scriptstyle ON}}}\) ) and electric field ( \(E\) -field) distribution in high-voltage AlGaN/GaN high electron mobility transistors (HEMTs) on a Si substrate based on pulsed \(I\) – \(V\) measurements, electroluminescence (EL) microscopy, and 2-D physics-based numerical device simulations. It is found that the dynamic \(R_{\mathrm{{\scriptstyle ON}}}\) increase has been significantly suppressed to below 10% at various temperatures ranging from −50 to 200 °C owing to the effective and robust compensation of deep acceptor-like trap states at the AlN/GaN (passivation/cap) interface by the additional positive polarization charges induced in the epitaxial AlN thin passivation layer grown in a plasma-enhanced atomic layer deposition system. To the best of our knowledge, this is the first time that highly suppressed current collapse in an AlGaN/GaN HEMT on a Si substrate within a wide temperature range is ever reported. By monitoring the dynamic \(R_{\mathrm{{\scriptstyle ON}}}\) for 100 consecutive 133-kHz switching cycles, its variation is observed to be less than 2.5%, indicating excellent stability of the passivation effectiveness. The electric field in an AlN-passivated device is found to be well confined at the drain-side gate edge, as shown in EL measurement and numerical simulation results. This phenomenon directly suggests that the virtual gate effect arising from surface trap charging has been effectively alleviated by the AlN passivation technique. [ABSTRACT FROM AUTHOR]