公开(公告)号：US20240072180A1

公开(公告)日：2024-02-29

申请号：US17896711

申请日：2022-08-26

Applicant: GlobalFoundries U.S. Inc.

Inventor： Saloni Chaurasia ,  Jeffrey Johnson ,  Vibhor Jain ,  Crystal R. Kenney ,  Sudesh Saroop ,  Teng-Yin Lin ,  John J. Pekarik

IPC: H01L29/93 ,  H01L29/10 ,  H01L29/66

CPC classification number: H01L29/93 ,  H01L29/1095 ,  H01L29/66174

Abstract: Structures for a varactor diode and methods of forming same. The structure comprises a first semiconductor layer including a section on a substrate, a second semiconductor layer on the section of the first semiconductor layer, a third semiconductor layer on the second semiconductor layer, and a doped region in the section of the first semiconductor layer. The section of the first semiconductor layer and the doped region have a first conductivity type, and the second semiconductor layer comprises silicon-germanium having a second conductivity type opposite to the first conductivity type, and the third semiconductor layer has the second conductivity type. The doped region contains a higher concentration of a dopant of the first conductivity type than the section of the first semiconductor layer. The second semiconductor layer abuts the first section of the first semiconductor layer along an interface, and the doped region is positioned adjacent to the interface.