Process forms stoichiometric, continuous, strongly bonded titanium hydrogen isotopic films. Films have thermal and electrical conductivities approximately the same as bulk pure titanium, ten times greater than those of usual thin films

Alger, D. L.

Cooper, D. W.

Steinberg, R.

English

NASA Technical Reports Server

Mah 1975	 B75-10001 
NASA TECH BRIEF 
Lewis Research Center 
NASA Tech Briefs announce new technology derived from the U.S. space program. They are issued to encourage 
commercial application. Tech Briefs are available on a subscription basis from the National Technical Information 
Service, Springfield, Virginia 22151. Requests for individual copies or questions relating to the Tech Brief program may 
be directed to the Technology Utilization Office, NASA, Code KT, Washington, D.C. 20546. 
A Superior Process for Forming
Titanium Hydrogen Isotopic Films 
I.
A unique process has been developed for forming 
stoichiometric, continuous, strongly bonded titanium 
hydrogen isotopic films. The films have thermal and 
electrical conductivities approximately the same as bulk 
pure titanium, ten times greater than those of usual thin 
films. 
Continuous thin films of stoichiometric titanium dthy-
dride, dideuteride, or ditritide can be formed by this 
process. Films made with deuterium or tritium are useful 
as superior neutron generator targets, corrosion resistant 
coatings, hydrogen diffusion barriers, or for storing 
hydrogen. Previously, TiH 2 and TiD2 compounds have 
been formed but only as powder. Titanium films partly 
loaded with deuterium or tritium are in general use as 
neutron generator targets, however, such films approxi-
mate TiD 1 or TiT 1 and consist of a two-phase mixture of 
titanium metal and titanium deuteride or tritide. Pre-
viously made films are porous and brittle, have poor 
electrical and thermal conductivity, and flake into powder 
at near stoichiometric conditions. 
This film forming process is carried out in a modified 
commercial ultrahigh vacuum system capable of approxi-
mately 10- 1 1 torr vacuum. The substrates are chemically 
cleaned and then placed in-the vacuum system for final 
surface preparation by sputter etching in a low pressure 
argon atmosphere. The argon is pumped out and a 
titanium sublimator first coats the shroud surrounding the 
substrate holder with a thin film of titanium to getter 
contaminant gas molecules, and then deposits titanium on 
the substrates until the desired film thickness is achieved. 
A commercial quartz crystal thickness monitor is used to 
measure film thickness in situ. After the titanium film is 
formed, the hydrogen isotope gas is bled into the vacuum 
chamber where it is absorbed by the titanium.
Titanium deuteride films approximately three mi-
crometers thick have been made by this process which had 
a chemical composition of T0 196 . The titanium films 
were deposited in 16 to 18 hours with the sublimator 
running at an 0.5 grams/hour rate. Approximately 100 
hours were required to form the titanium dideuteride film 
in a deuterium atmosphere of 10- s torr and with the 
substrates at a temperature of 282 K (48°F). Films were 
formed on platinum, glass and copper substrates. Stoichio-
metric films can also be formed at higher pressures or 
higher substrate temperatures in correspondingly shorter 
times provided that the rate of gas diffusion into the 
titanium film is greater than the rate of adsorption at the 
surface. 
Notes: 
1. This process can also be utilized for hydride, deuteride 
or tritide formation of other materials that absorb and 
diffuse hydrogen readily, e.g., zirconium and erbium. 
2. Requests for further information may be directed to: 
Technology Utilization Officer 
Lewis Research Center 
21000 Brookpark Road 
Cleveland, Ohio 44135 
Reference: B75-10001 
Patent Status:. 
Inquiries concerning rights for the commercial use of 
this invention should be addressed to: 
NASA Patent Counsel 
Mail Stop 500-113 
Lewis Research Center 
21000 Brookpark Road 
Cleveland, Ohio 44135 
Source: R. Steinberg, D.L. Alger, 
and D.W. Cooper
Lewis Research Center
(LEW- 12083) 
Category 03,05 
This document was prepared under the sponsorship of the National 	 Government assumes any liability resulting from the use of the 
Aeronautics and S pace Administration. Neither the United States 	 information contained in this document, or warrants that such use 
Government nor any person acting on behalf of the United States 	 will be free from privately owned rights.
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A superior process for forming titanium hydrogen isotopic films

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