High voltage diode and manufacturing method thereof

Abstract

The invention provides a manufacturing method of a high-voltage diode, which comprises the following steps: providing a first substrate of a first conductivity type and a second substrate of a secondconductivity type; extending upwards from the upper surface of the first substrate to form a first epitaxial layer of the second conductivity type, and extending upwards from the lower surface of thesecond substrate to form first sub-doped regions of the first conductivity type which are arranged at intervals; connecting the lower surface of the second substrate with the upper surface of the first epitaxial layer through a bonding process; extending downwards from the upper surface of the second substrate to form second sub-doped regions of the first conductivity type, and the first sub-dopedregions and the second sub-doped regions jointly forming a first doped region; extending upwards from the upper surface of the second substrate to form a second epitaxial layer of the second conductivity type; extending downward from the upper surface of the second epitaxial layer to form a second doped region of the second conductivity type; forming a front metal layer on the upper surface of the second doped region; and forming a back metal layer on the lower surface of the first substrate. The invention also provides a high-voltage diode.

Description

technical field [0001] The invention relates to the field of semiconductor chips, in particular to a high-voltage diode and a manufacturing method thereof. Background technique [0002] High-voltage diodes are usually able to withstand very high voltages, usually above 2000V, and can pass large currents. They are semiconductor devices that are widely used. According to different application occasions, high-voltage diodes have different requirements on their performance, so the focus of design is also different. When applied to ordinary rectification, high breakdown voltage and low forward voltage drop are required, and the requirements for reverse recovery characteristics are not very high. When applied to switching circuits, the switching speed is required to be high, so the key to design is to shorten the reverse recovery time and reduce the forward voltage drop. When applied to freewheeling circuits, not only must it have fast recovery speed and low forward voltage drop...

Images