公开(公告)号：US10217852B1

公开(公告)日：2019-02-26

申请号：US15948486

申请日：2018-04-09

Applicant: GLOBALFOUNDRIES Inc.

Inventor： Qizhi Liu ,  Vibhor Jain ,  James W. Adkisson ,  James R. Elliott

IPC: H01L23/552 ,  H01L29/737 ,  H01L29/10 ,  H01L21/306 ,  H01L29/06 ,  H01L29/66 ,  H01L29/04

Abstract: Device structures and fabrication methods for heterojunction bipolar transistors. A trench isolation region surrounds an active region that includes a collector, and a base layer includes a first section composed of a single-crystal semiconductor material that is arranged over the active region and a second section composed of polycrystalline semiconductor material that is arranged over the trench isolation region. A first semiconductor layer of the second section of the base layer is removed selective to a second semiconductor layer of the second section of the base layer to define a gap arranged in a vertical direction between the second semiconductor layer of the second section of the base layer and the trench isolation region. An emitter is formed on the first section of the base layer.

公开(公告)号：US09231087B2

公开(公告)日：2016-01-05

申请号：US14677303

申请日：2015-04-02

Applicant: GLOBALFOUNDRIES INC.

Inventor： John J. Benoit ,  James R. Elliott ,  Peter B. Gray ,  Alvin J. Joseph ,  Qizhi Liu ,  Christa R. Willets

IPC: H01L29/732 ,  H01L29/66 ,  H01L29/06 ,  H01L29/737

CPC classification number: H01L29/732 ,  H01L29/0649 ,  H01L29/0821 ,  H01L29/0826 ,  H01L29/66272 ,  H01L29/7371 ,  H01L29/7378

Abstract: Device structures, design structures, and fabrication methods for a bipolar junction transistor. A first layer comprised of a first semiconductor material and a second layer comprised of a second semiconductor material are disposed on a substrate containing a first terminal of the bipolar junction transistor. The second layer is disposed on the first layer and a patterned etch mask is formed on the second layer. A trench extends through the pattern hardmask layer, the first layer, and the second layer and into the substrate. The trench defines a section of the first layer stacked with a section of the second layer. A selective etching process is used to narrow the section of the second layer relative to the section of the first layer to define a second terminal and to widen a portion of the trench in the substrate to undercut the section of the first layer.