Semiconductor device including trench contact structure and manufacturing method

Abstract

A semiconductor device including a trench contact structure and a manufacturing method are provided. The semiconductor device is proposed. A trench gate structure 102 extends from a first surface 104into a silicon carbide semiconductor body 106 along a vertical direction y. A trench contact structure 108 extends from the first surface into the silicon carbide semiconductor body along the verticaldirection. A source region 130 of a first conductivity type and a body region 110 of a second conductivity type adjoin a first sidewall 112 of the trench gate structure 102. A diode region 114 of thesecond conductivity type adjoins a second sidewall 116 of the trench gate structure opposite to the first sidewall. A shielding region 118 of the second conductivity type adjoins a bottom 120 of thetrench contact structure, the shielding region being arranged at a lateral distance ld to the trench gate structure.

Description

technical field [0001] The present disclosure relates to semiconductor devices, in particular to semiconductor devices comprising a trench contact structure in a silicon carbide semiconductor body. Background technique [0002] Semiconductor devices based on silicon carbide (SiC) benefit from SiC's high bandgap and breakdown strength. However, at the interface between the SiC semiconductor body and the dielectric layer, for example the gate dielectric of a transistor cell of a SiC-MOSFET (SiC Metal-Oxide-Semiconductor Field-Effect Transistor), a large number of interface states are formed, Depending on the operating state of the SiC-MOSFET, the interface states can be occupied by more or less charge carriers. The charge carriers occupying the interface state affect the mobility and concentration of the free charge carriers that form the field-controlled transistor channel when the transistor cell is switched on. Furthermore, the high breakdown strength of SiC is often not ...

AI Technical Summary

Problems solved by technology

Furthermore, the high breakdown strength of SiC is usually not fully exploited because the electric field strength occurring in the gate dielectric and the reliability of the gate dielectric often limit the dielectric strength of SiC-MOSFETs

Images