Vapor phase deposition process forms a heavily doped n-region on a melt-grown p-type gallium antimonide substrate. HCl transports gallium to the reaction zone, where it combines with antimony hydride and the dopant carrier, hydrogen telluride. Temperatures as low as 400 degrees C are required

Clough, R.

Richman, D.

Tietjen, J.

English

NASA Technical Reports Server

November 1970	 Brief 70-10500 
NASA TECH BRIEF . 
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 Clearinghouse for Federal Scientific and Technical 
Information, Springfield, Virginia 22151. Requests for individual copies or questions relating to the Tech Brief program may 
be directed to the Technology Utilization Division, NASA, Code UT, Washington, D.C. 20546. 
P-N Junctions Formed in Gallium Antimonide 
1	 HTe+H2 
4	 SbH+H2 
H2
	
GaSb	 Continues 
Substrate to Exhaust 
4	
I' 
I _ _ Ii- 
__ 
HCI+H2'	 'Ga)	 I I Gallium I Reaction I	 Deposition I 
Zone	 Zone	 Zone
Vapor-Deposited. 
Tellurium-Doped GaSb
Melt-Grown 
GaSb Substrate 
Figure 1. Vapor Deposition Apparatus 
A recent prediction that a Gunn oscillator (source 
of microwave energy) prepared from gallium antimo-
nide (GaSb) should have desirable properties of lower 
threshold field and higher efficiency than a device 
prepared from gallium arsenide, has generated consid-
erable interest in developing new techniques for the 
preparation of p-n junctions in single crystal GaSb. 
Undoped GaSb is inherently p-type and would require 
a suitable n-type dopant, e.g., tellurium or selenium 
to form the n-region. 
A vapor phase deposition process has been devel-
oped, using the experimental apparatus shown in 
Figure 1, to form the heavily doped n-region. A melt-
grown p-type GaSb substrate is placed in the deposi-
tion zone; HCl is introduced over the gallium boat 
to transport the gallium (predominately a subchloride) 
to the reaction zone, where it combines with antimony 
hydride (SbH 3 ) and the dopant carrier, hydrogen
Figure 2. Cross Section of GaSb Device 
Formed with Vapor Deposited n-Layer 
telluride (H 2Te), to form n-type GaSb on the sub-
strate. Since the growth rate of GaSb is quite low, 
less than 5 microns/hr, and Te has a high diffusion 
constant, temperatures as low as 400°C are required 
to prevent out-diffusion of Te into the substrate. 
A cross section of a typical n-p structure is shown 
in Figure 2. Net electron concentrations of 2 X 1017 
e/cm 3
 in the n-region have been obtained. Funda-
mental factors which limit the growth of GaSb from 
the vapor phase are the low melting point of GaSb 
(712T) and the low vapor pressure of antimony 
(1 mm). 
Notes: 
1. Further development of the vapor deposition would 
enable Gunn diodes, electroluminescent devices 
and transistors to be fabricated from high quality 
GaSb. (continued overleaf) 
This document was prepared under the sponsorship of the National 
Aeronautics and Space Administration. Neither the United States 
Government nor any person acting on behalf of the United States
Government assumes any liability resulting from the use of the 
information contained in this document, or warrants that such use 
will be free from privately owned-rights.
https://ntrs.nasa.gov/search.jsp?R=19700000482 2020-03-17T00:35:05+00:00Z
2. Requests for further information may be directed 
to:
Technology Utilization Officer 
Headquarters 
National Aeronautics 
and Space Administration 
Washington, D.C. 20546 
Reference: B70-10500
Patent status: 
Inquiries about obtaining rights for the commercial 
use of this invention may be made to NASA, Code 
GP, Washington, D.C. 20546. 
Source: J. Tietjen, R. Clough, D. Richman of

RCA Laboratories
under contract to

Electronic Research Center
(ERC- 10302) 
Brief 70-10500	 Category 01


P-n junctions formed in gallium antimonide

Abstract

Similar works

Full text

Available Versions

NASA Technical Reports Server