Epitaxial structure of power semiconductor device and its preparation method

Abstract

The invention discloses an epitaxial structure of a power semiconductor device and a preparation method thereof, belonging to the technical field of semiconductors. The epitaxial structure of the power semiconductor device includes a Si substrate, an AlN buffer layer, and a GaN epitaxial layer stacked in sequence, and the floating bonds on the first surface of the AlN buffer layer include one of Al bonds, Ga bonds, and N bonds or Multiple, the first surface is the surface on which the GaN epitaxial layer is provided for the AlN buffer layer. The present invention sets the suspended bonds on the surface of the GaN epitaxial layer by changing the AlN buffer layer, which can effectively avoid the -OH bond and -O bond from affecting the growth of the GaN crystal, so that the growth rate of the GaN crystal on each region of the AlN buffer layer is basically the same, Reduce the formation of defects, improve the crystal quality of GaN epitaxial layer, realize high-quality GaN layer, and ensure the performance of power semiconductor devices.

Description

technical field [0001] The invention relates to the technical field of semiconductors, in particular to an epitaxial structure of a power semiconductor device and a preparation method thereof. Background technique [0002] Power semiconductor devices, also known as power electronic devices (English: Power Electronic Device), are high-power electronic devices used for power conversion and control circuits of power equipment (the current is tens to thousands of amps, and the voltage is hundreds of volts or more. ). Power semiconductor devices include insulated gate bipolar transistors (English: Insulated Gate Bipolar Transistor, referred to as: IGBT), metal oxide semiconductor field effect transistors (English: Metal-Oxide-Semiconductor Field-Effect Transistor, referred to as: MOSFET) and other devices, these The epitaxial structure at the bottom of the device is the same. [0003] With the rapid development of wide bandgap semiconductor materials represented by silicon carb...

AI Technical Summary

Problems solved by technology

-OH suspension bonds and -O suspension bonds will affect the growth of GaN crystals, resulting in inconsistent growth rates of GaN crystals in different regions of the AlN layer, forming defects in the GaN layer, reducing the crystal quality of the GaN layer, resulting in the inability to obtain high-quality GaN layer, which seriously affects the performance of power semiconductor devices

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