Lateral diffusion eGaN HEMT device integrating reverse diode and embedded drain electrode field plate

Abstract

The invention discloses a lateral diffusion eGaN HEMT device integrating a reverse diode and an embedded drain electrode field plate. The device comprises a GaN buffer layer, an AlGaN barrier layer, agate electrode, an under-gate insulating layer, a source electrode, a source electrode extension section, a source electrode field plate, an MIS schottky diode extension section, an MIS schottky diode insulating layer, a p-type GaN or groove, a drain electrode, a passivation layer and an AlN staggered-layer drain electrode embedded field plate, wherein the MIS schottky diode insulating layer is prepared in the middle region, towards the MIS schottky diode extension section and the AlGAN barrier layer surface, of the source electrode field plate; the side, close to the drain electrode, of thediode adopts the p-type GaN or groove, so that the breakdown characteristic of the device is improved; the embedded staggered-layer field plate is adopted below the drain electrode, so that anti-breakdown capability of the drain electrode to the substrate is improved; the design of the staggered layer is suitable for the gradual change distribution of the drain electrode electric field from rightto left, so that the breakdown characteristic of the device is improved; and the source electrode field plate is extended, the gate electrode is wrapped, the MIS schottky diode is formed on the gate drain side, and the diode is made into a block isolation mode, so that the drain electrode current is greatly improved.

Description

technical field [0001] The invention relates to the field of semiconductor devices, in particular to a lateral diffusion eGaN HEMT device integrating reverse diodes and embedded drain field plates. Background technique [0002] The third-generation semiconductor materials represented by GaN and AlGaN have extremely strong spontaneous polarization. When GaN / AlGaN heterojunction is formed, the piezoelectric polarization caused by the difference in lattice constant is also very strong. In addition, there is a large conduction band discontinuity in the conduction bands of GaN and AlGaN materials, so that a natural bulk density of up to 10 can be formed in the GaN / AlGaN heterojunction 19 The order of magnitude of high-concentration two-dimensional electron gas (2DEG). [0003] Compared with Si-based MOSFET, the structure of high electron mobility transistor (GaN HEMT) made of GaN / AlGaN heterostructure is simpler, no doping is required, and the interlayer material has a high band...

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Problems solved by technology

[0005] At this stage, the conventional eGaN HEMT device structure mainly has the following two major disadvantages: there is no integrated reverse diode, and when the device works in the reverse direction, the work loss is large due to the high reverse conduction voltage drop; in addition, its reverse There is also the problem that the conduction characteristics deteriorate sharply with the increase of current and temperature; there is no light depletion region near the drain side of the gate, and there is no embedded field plate, and the device has a strong peak electric field on the gate side, making the device's The gate and drain are easily broken down, so the breakdown characteristics are poor

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