Dismiss
InnovationQ will be updated on Sunday, Oct. 22, from 10am ET - noon. You may experience brief service interruptions during that time.
Browse Prior Art Database

Fully Planarized Double Poly Self Aligned Bipolar Transistor with Self Aligned Chem Mech Polished Emitter and Collector Contact

IP.com Disclosure Number: IPCOM000109561D
Original Publication Date: 1992-Sep-01
Included in the Prior Art Database: 2005-Mar-24
Document File: 3 page(s) / 197K

Publishing Venue

IBM

Related People

Chuang, C: AUTHOR [+2]

Abstract

Disclosed is a structure/process for a high performance, double-poly self-aligned bipolar transistor with self-aligned chem-mech polished emitter and collector contact. The structure/process offers fully-planarized in-line emitter, base, and collector contacts to ease the contact/stud process and BEOL integration.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

Fully Planarized Double Poly Self Aligned Bipolar Transistor with Self Aligned Chem Mech Polished Emitter and Collector Contact

       Disclosed is a structure/process for a high performance,
double-poly self-aligned bipolar transistor with self-aligned
chem-mech polished emitter and collector contact.  The
structure/process offers fully-planarized in-line emitter, base, and
collector contacts to ease the contact/stud process and BEOL
integration.

      Double-poly self-aligned bipolar transistor has been known for
its high performance and is now an industrial standard.  However, the
severe topography of the double-poly structure has been limiting its
interfacing/integration with the BEOL processes and the extendibility
to scaled design rules.  As shown in the schematic cross-section in
Fig. 1, the topography of a double-poly self-aligned bipolar
transistor consists of the base-poly stack, the dielectric stack over
the base-poly, and the emitter-poly stack.  The severe topography has
direct impact on the emitter-poly definition process where emitter-
poly rail can form along the edges of the base-poly stack during the
emitter-poly definition process and substantial over-etch is
necessary to eliminate the rail, thus impacting directly on the
groundrules, such as the emitter-poly to emitter-opening overlay,
emitter-poly to emitter-poly spacing, and emitter-poly to base
contact spacing.  The severe topography may also cause problems in
step coverage and etch- stop in stud/contact hole etching process as
well as possible void formation in stud filling process.

      The disclosed structure/process possesses the following
features to alleviate the aforementioned problems/concerns:
(A)  Self-aligned fully-planarized chem-mech polished (CMP) emitter-
and collector-contact: After the emitter-poly deposition and
implantation of As into the emitter-poly (as in the con...