Power diode and preparation method thereof

Abstract

The invention provides a power diode. The power diode comprises a substrate of a first conductivity type, a first epitaxial layer of a second conductivity type, buried layers of a second conductivitytype, a second epitaxial layer of a second conductivity type, a first injection region of a first conductivity type, a second injection region of a second conductivity type, a gate pole metal layer, anegative electrode metal layer and a positive electrode metal layer, wherein the first epitaxial layer of the second conductivity type is formed on the substrate; the buried layers of the second conductivity type are formed at intervals and extend from the upper surface of the first epitaxial layer to the interior of the first epitaxial layer; the second epitaxial layer of the second conductivitytype is formed on the first epitaxial layer; the first injection region of the first conductivity type is formed in the second epitaxial layer and corresponds to the buried layers; the second injection region of the second conductivity type is located on the upper surface of the second epitaxial layer; the gate pole metal layer is positioned on the upper surface of the first injection region; thenegative electrode metal layer is formed on the upper surface of the second injection region; and the positive electrode metal layer is formed on the lower surface of the substrate. The invention further provides a preparation method of the power diode. The reverse breakdown voltage of the power diode is improved, and the leakage current and the power consumption of the circuit are reduced.

Description

technical field [0001] The invention relates to the field of design and manufacture of semiconductor discrete devices, in particular to a power diode and a preparation method thereof. Background technique [0002] Power diodes are the most basic components in the field of power electronics, and their unidirectional conductivity can be used for rectification, clamping, and freewheeling of high-voltage circuits. Power rectifier diodes have a much larger junction area than ordinary diodes, and can pass thousands of amperes of current. Power rectifier diodes are mainly used in various rectification, switching, and freewheeling circuits. [0003] With the development of power electronics technology, higher technical index requirements are put forward for power diodes, mainly including low forward voltage drop, low on-resistance, higher reverse breakdown voltage and fast and soft reverse recovery characteristics. At present, power diodes using traditional structures and processe...

AI Technical Summary

Problems solved by technology

At present, power diodes using traditional structures and processes often only have a high reverse breakdown voltage, while other characteristics are not very good, especially the long reverse recovery time and hard reverse recovery characteristics, which not only cause the entire circuit The waste of system power consumption is more likely to cause adverse current and voltage oscillations in the circuit due to too sudden reverse recovery, resulting in power supply ripple or electromagnetic interference, destroying the entire circuit, and even causing the failure of components in the circuit

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