Browse Prior Art Database

Simplified Process Flow for Complementary Metal Oxide Semiconductor Manufacturing

IP.com Disclosure Number: IPCOM000114784D
Original Publication Date: 1995-Jan-01
Included in the Prior Art Database: 2005-Mar-29
Document File: 2 page(s) / 40K

Publishing Venue

IBM

Related People

Rauscher, W: AUTHOR

Abstract

Disclosed is a process for Complementary Metal Oxide Semiconductor (CMOS) manufacturing simplified by using thermal and pyrolytic silicon oxides as cell isolation and a selectively deposited silicon epitaxial layer as planarisation layer.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 83% of the total text.

Simplified Process Flow for Complementary Metal Oxide Semiconductor
Manufacturing

      Disclosed is a process for Complementary Metal Oxide
Semiconductor (CMOS) manufacturing simplified by using thermal and
pyrolytic silicon oxides as cell isolation and a selectively
deposited silicon epitaxial layer as planarisation layer.

      Essential steps of the CMOS manufacturing process flow are the
cell isolation by a thick field oxide (SROX) and the electrical
connection between storage trench and source/drain region by a thin
strap of selectively deposited epitaxial silicon and titanium
silicide.

      In the conventional CMOS process the formation of the SROX
leads to an unwanted topography of the wafer surface and the minimum
cell size is limited by the birds beak of the SROX.  This limitation
could be avoided by a shallow trench isolation which complicates the
process flow and requires processes which are not yet well tested
under manufacturing conditions.  Other problems inherent are the
demolition of the strap and shorts between wordline and substrate.
So-called "titan stringers" affect the reliability of the devices.

      In the proposed process flow the pad films already deposited
are used as cell isolation and the trenches between the cell
isolations are filled with selectively deposited epitaxial silicon.
This step simultaneously leads to a reliable and electrically
conductive connection between storage trench and source/drain region
and avoids th...