Patent ID: 11961904
Assignee: INFINEON TECHNOLOGIES AG
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 20:
21. A method of manufacturing a semiconductor device, the method comprising:
implanting first dopants through a first surface section, exposed by an implant mask opening, of a first surface of a silicon carbide body;
forming a trench extending from the first surface, through which the first dopants were implanted, into the silicon carbide body, wherein the trench comprises a first sidewall surface and an opposite second sidewall surface;
forming a spacer mask covering at least the first sidewall surface;
implanting second dopants through a portion of a bottom surface of the trench exposed by the spacer mask, wherein the first dopants and the second dopants have a same conductivity type; and
activating the first dopants and the second dopants, wherein:
the first dopants form a doped top shielding region adjoining the second sidewall surface; and
the second dopants form a doped buried shielding region adjoining the bottom surface,

at least one of:
wherein:
at least a portion of the second dopants are implanted with an implantation beam axis tilted with respect to a vertical direction at an implant angle in a vertical plane orthogonal to a horizontal longitudinal extension of the trench; and
the implantation beam axis is directed to the second sidewall surface;

wherein forming the spacer mask comprises exposing and recessing a portion of the bottom surface of the trench; or
wherein forming the spacer mask comprises:
forming an auxiliary mask layer filling the trench and covering the first surface; and
selectively removing a first auxiliary mask layer portion that adjoins the second sidewall surface, wherein a residual second auxiliary mask layer portion covering at least the first sidewall surface forms the spacer mask.