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.