Preparation method of low-voltage fast recovery diode and diode

Abstract

The invention provides a preparation method of a low-voltage fast recovery diode and a diode. The preparation method comprises the following steps of preparing an N-type semiconductor substrate, and forming an N-type epitaxial layer on the substrate, forming a thermal oxide layer on the N-type epitaxial layer through field oxygen, exposing the N+ open ion implantation window region through exposure and etching of an N+ cut-off ring mask, performing high-energy ion implantation of ion phosphorus in the window region of the N+ open, exposing and etching a PLS main junction region through a PLS main junction mask, and injecting boron into high-energy ions, performing high-temperature propulsion to form a P well and an N well, sputtering aluminum on the front surface of the device, and forming a positive electrode through exposure and etching of a metal mask, depositing a passivation layer on the surface of the positive electrode, and forming a device protection structure through exposure and etching of a passivation layer mask, and evaporating on the back surface of the N-type semiconductor substrate to form a metal silver layer, and leading out a negative electrode. Under the condition that the characteristics are not changed, a hole-level process is omitted, so that the production efficiency of a product is improved, and the production cost of the device is reduced.

Description

technical field [0001] The invention belongs to the technical field of diodes, and in particular relates to a preparation method of a low-voltage fast recovery diode and the diode. Background technique [0002] Fast recovery diode (FRD for short) is a semiconductor diode with good switching characteristics and short reverse recovery time. It is mainly used in electronic circuits such as switching power supplies, PWM pulse width modulators, and frequency converters. Freewheeling diodes or damping diodes are used. [0003] The fast recovery diode adopts gold-doped, simple diffusion and other processes in the manufacturing process, which can obtain high switching speed and high withstand voltage at the same time. At present, the high-performance fast recovery diode processing technology mainly adopts five-layer photolithography, which has low production efficiency and high production cost. [0004] To sum up, there is an urgent need for a process that can solve the above-ment...

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Problems solved by technology

[0005] In view of the shortcomings of the above-mentioned prior art, the object of the present invention is to provide a method for preparing a low-voltage fast recovery diode and the diode, aiming at solving the problems of low production efficiency and high production cost in the prior art

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