Browse Prior Art Database

Epitaxial Growth of Bismuth Silicate by CVD

IP.com Disclosure Number: IPCOM000119348D
Original Publication Date: 1991-Jan-01
Included in the Prior Art Database: 2005-Apr-01
Document File: 1 page(s) / 38K

Publishing Venue

IBM

Related People

Taylor, RC: AUTHOR

Abstract

Disclosed is a simple method for deposition of epitaxial films of bismuth silicate using only a single source material and a subsequent reaction involving the substrate. Previous chemical vapor deposition methods [1,2] have required two source materials and a bismuth silicate substrate.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 86% of the total text.

Epitaxial Growth of Bismuth Silicate by CVD

      Disclosed is a simple method for deposition of epitaxial
films of bismuth silicate using only a single source material and a
subsequent reaction involving the substrate. Previous chemical vapor
deposition methods [1,2] have required two source materials and a
bismuth silicate substrate.

      Bismuth silicate (Bi12SiO20) is of interest since it exhibits
both photoconductivity and electro-optic effects and has potential
for many applications, such as spatial light modulators and holograms
recording devices.  Single crystal thin films would be beneficial for
some of these applications.  Films of bismuth silicate (Bi4Si3O12)
have been grown on fused quartz plates by hydrolysis of BiCl3 vapor
on the plates at 850oC.   The BiCl3 is vaporized at 180oC and carried
by inert gas to the substrate where it is hyrolyzed to Bi2O3 by a
separately introduced stream of H2O and O2 gases.  The Bi2O3 solid
then undergoes an interfacial reaction with the quartz to produce
polycrystalline Bi4Si3O12 .  By appropriate adjustment of growth
temperature and vapor species concentration it would be possible to
grow single-crystal Bi12SiO20 is cubic with a lattice parameter a =
10.107 Ao while SiO2 is hexagonal with a = 4.913 Ao . Twice the SiO2
lattice parameter is 9.83, less than a 3 percent mismatch to
Bi12SiO20, so that an epitaxial accommodation seems impossible,
though slightly strained, on c-axis SiO2 .  A similar accommodation
oc...