Gallium nitride heterojunction MIS grid-control power diode and manufacturing method thereof

Abstract

The invention relates to the technical field of semiconductor devices, in particular to a gallium nitride heterojunction MIS grid-control power diode and a manufacturing method thereof. The gallium nitride heterojunction MIS grid-control power diode is characterized in that the two-dimensional electron gas below Schottky metal is exhausted by etching the barrier layer below the anode Schottky metal, insulating media and Schottky metal are precipitated in the etched groove to form a Schottky metal / insulting medium / semiconductor (MIS) grid-control structure, the MIS grid-control structure can control the on and off of a device and can effectively reduce the reverse leakage of the device and increase the reverse voltage resistance of the device; an Ohm / Schottky metal short-circuit mixed anode is formed at the anode of the diode, and low positive turning-on voltage of the device can be achieved. The gallium nitride heterojunction MIS grid-control power diode has the advantages of high reverse voltage resistance, high breakover currents, low turning-on voltage, low breakover resistance, low power consumption and the like. The manufacturing method is especially applicable to the gallium nitride heterojunction diode.

Description

technical field [0001] The invention relates to the technical field of semiconductor devices, in particular to a gallium nitride heterojunction MIS (Schottky metal / insulator / semiconductor) gate-controlled power diode and a manufacturing method thereof. Background technique [0002] As a typical representative of the third-generation wide-bandgap semiconductor, gallium nitride (GaN) has many excellent characteristics: high critical breakdown electric field (~3.5×10 6 V / cm), high electron mobility (~2000cm 2 / v·s), high two-dimensional electron gas (2DEG) concentration (~10 13 cm -2 ) and good high temperature working ability, etc. High electron mobility transistor (HEMT) based on AlGaN / GaN heterojunction (or heterojunction field effect transistor HFET, modulation doped field effect transistor MODFET, hereinafter collectively referred to as HEMT devices) has been applied in the semiconductor field, especially in The field of radio frequency / microwave has been applied in wi...

AI Technical Summary

Problems solved by technology

However, limited by the metal-semiconductor contact between the Schottky metal and the GaN semiconductor, the traditional GaN heterojunction Schottky diode has a large turn-on voltage and the reverse leakage and withstand voltage are not ideal.

At present, people have proposed a variety of technologies to realize the low turn-on voltage and high withstand voltage of gallium nitride heterojunction diodes. In terms of forward turn-on voltage, there are groove technology and fluorine ion implantation technology, but its reverse leakage is limited. Due to the limitation of the Tertky contact barrier, the withstand voltage is still not ideal; in terms of reverse withstand voltage, there is a junction terminal structure, but the forward current of the device is limited by the current carrying capacity of the Schottky contact, and a larger turn-on voltage will Increase the forward working loss of the device, so the development of a GaN-based power diode with low forward turn-on voltage and high reverse withstand voltage is of great significance for practical applications

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