Browse Prior Art Database

High Conformality/High Quality Films by Thermal CVD/RTP

IP.com Disclosure Number: IPCOM000121158D
Original Publication Date: 1991-Jul-01
Included in the Prior Art Database: 2005-Apr-03
Document File: 1 page(s) / 44K

Publishing Venue

IBM

Related People

Dobuzinsky, DM: AUTHOR [+3]

Abstract

A process is described in the fabrication of semiconductors for depositing tetraethylorthosilicate (TEOS) oxide films which are of good quality suitable for trench isolation.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 90% of the total text.

High Conformality/High Quality Films by Thermal CVD/RTP

      A process is described in the fabrication of semiconductors for
depositing tetraethylorthosilicate (TEOS) oxide films which are of
good quality suitable for trench isolation.

      Thermal chemical vapor deposition (CVD) of TEOS/O3 films show
excellent conformality and good trench fill properties up to 1.3
aspect ratio; however, they tend to have cracks and defects when
thick (>700nm) films are deposited. This limits the use to thin oxide
trench collar fabrication. A new multistep conformal CVD trench fill
process is shown that results in improved quality, eliminates thick
film cracking, and extends the use of high conformal thermal CVD TEOS
films.

      Using conventional CVD equipment, a film is deposited with
TEOS/O3/O2 gases at 50 Torr pressure and 400 degrees C. This step is
followed by a rapid thermal anneal process (RTP) using a system
capable of annealing up to 1150 degrees C. When a film about 300-400
nm thick is deposited with TEOS/ozone and annealed in a RTP system
for 30 seconds at 800-1150 degrees C in Ar ambient or (N2, O2),
densification and stress reduction results.  The thermal CVD TEOS/RTP
process is repeated until the desired film thickness is achieved. RTP
annealing reduces the film thickness range from 6 to 12% in the
temperature range cited.

      Thick films of 1.26 mm can be deposited without defects or
cracking when the multistep process is used. Densified TEOS oxide
e...