Power diode device and preparation method thereof

Abstract

The invention discloses a power diode device. The power diode device comprises a substrate, a buffering layer, an epitaxial layer, an ALN (Aluminum nitride) layer, a field limiting ring, an annular field plate and a metal layer which are arranged in a cascading manner, wherein the metal layer forms a schottky junction; the epitaxial layer is electrically connected with a cathode; the metal layer is connected with an anode; a plurality of annular concave and convex parts are formed on the annular field plate; the highest point of a convex part of the annular field plate is gradually raised from the inner side of a power component to the outer side; the lowest point of the annular field plate is gradually raised from the inner side of the power component to the outer side; the projection of the annular field plate closest to the center of the power diode device on the epitaxial layer is positioned in the filed limiting ring closest to the center; and the metal layer covers each concave part of the annular field plate.

Description

technical field [0001] The invention relates to a power diode device and a preparation method thereof. Background technique [0002] For power diode devices to be able to withstand high voltages, advanced terminal structure designs must be used in the device structure. Its structure is as attached figure 1 As shown, the function of this terminal structure is to weaken the electric field enhancement peak at the edge of the electrode, flatten the electric field distribution, and avoid premature breakdown of the device. Therefore, in the design process of high-power Schottky devices, after determining the doping concentration and thickness of the voltage blocking layer, the design of the terminal structure around the Schottky electrodes will determine whether the device can withstand the required high voltage. [0003] The guard ring is the most commonly used terminal structure for power diode devices. Its manufacturing process is very mature for silicon-based devices. As sho...

AI Technical Summary

Problems solved by technology

In the traditional silicon device process, the lattice damage caused by ion implantation can be completely removed only by thermal annealing (generally at a temperature of about 1100 degrees); It is possible to remove the lattice damage caused by ion implantation only with a high degree of heat treatment

The heat treatment at 1500 degrees can decompose the GaN material on the surface of the device, reduce the Schottky barrier, increase th

Images