Semiconductor device and manufacturing method thereof

Abstract

The invention discloses a semiconductor device and a manufacturing method thereof, and belongs to the technical field of semiconductors. The semiconductor device comprises a plurality of cells which are the same in structure and are sequentially connected with one another, wherein each cell comprises an N-type doped substrate, an N-type lightly doped epitaxial layer, a diffused P-type well region, a first P-type heavily dope region, an N-type heavily dope region, an oxidation layer, a metal cathode, a second P-type heavily doped region and a metal anode; the N-type lightly doped epitaxial layer is located on the N-type doped substrate; the diffused P-type well region is located in the N-type lightly doped epitaxial layer; the first P-type heavily dope region and the N-type heavily dope region are located in the diffused P-type well region; the oxidation layer is located on the upper surfaces of the N-type lightly doped epitaxial layer and the diffused P-type well region; the metal cathode covers the overall cells; and the second P-type heavily doped region and the metal anode are located on the lower surface of the N-type doped substrate. According to the semiconductor device disclosed by the invention, a semiconductor material which is opposite to the substrate in the doping type is injected into the back surface of the substrate, so that, on one hand, holes are injected into the N-type substrate and the N-type lightly doped epitaxial layer through P-type heavily doped back injection, the semiconductor device has two carrier currents, namely a hole current and an electron current, and the current density of the device is increased; and on the other hand, the reverse withstand voltage of the device can be improved.

Description

technical field [0001] The invention belongs to the technical field of semiconductors, and in particular relates to a semiconductor device and a manufacturing method thereof. Background technique [0002] The constant current source is a commonly used electronic equipment and device, and it is widely used in electronic circuits. The constant current source is used to protect the entire circuit, even if the voltage is unstable or the load resistance changes greatly, it can ensure the stability of the supply current. A constant current diode (CRD, Current Regulative Diode) is a semiconductor constant current device, which uses a two-terminal junction field effect transistor as a constant current source instead of an ordinary constant current source composed of multiple components such as transistors, voltage regulator tubes, and resistors. It can maintain a constant current value within a certain working range. When it works in the forward direction, it is a constant current ...

AI Technical Summary

Problems solved by technology

However, the current constant current devices are still turned on when the reverse voltage is applied, and the range of the constant current region is generally narrow, and the constant current that can be provided is also low.

Images