The extremely fast ionization process in semiconductors offers a means of generating pulses that have sub -nanosecond rise times and high peak powers. There are several important applications of these pulses which require the duration of the generated pulse to be variable. This thesis investigates three methods of producing variable...
Vacuum evaporated dielectrics for use in MOS structures
were studied in this research project. Dielectric
films were deposited on substrates by electron bombardment
evaporation of sapphire and quartz source materials.
These deposited films were studied using infrared spectroscopy,
index of refraction, density, and dielectric constant
measurements. Etching tests were also...
The
experimental
procedure
for
evaporating
silicon
monoxide
together
with
the
methods
for
measuring
the film
thickness
have
been
investigated.
The
effects
of
various
process
parameters
on
the
rate
of
deposition,
such
as
source
temperature
and
source-substrate
distance,
have
been
studied.
The
uniformity
of
silicon
monoxide
films
deposited
by
this
particular...
The recent development of the laser has made possible
communications with a beam of coherent light.
Since coherent light offers great advantages over radio
in the areas of beam directivity and information capacity,
optical communication systems have been proposed
for many uses.
The first section of this thesis gives a...
Wideband tunnel-diode amplifiers using common-base
transistor stages for isolation were investigated for
stability criteria, frequency response, and the effects
of temperature and voltage supply fluctuations. For the
first time the full frequency spectrum of a tunnel-diode,
from d-c to the gigahertz (GHz) range, was able to be
utilized in an...
Some important factors that affect the dimensional
control of oxide films on silicon were studied. Both N- and
P-type silicon with resistivities in the range of
0.014 to 200 ohm-cm and a (111) surface orientation
were employed in this experiment. The etching rates of
silicon dioxide in hydrofluoric acid (111)...
This thesis presents a limited investigation of the effects
of various etches on the surface properties of silicon. Surface
recombination velocities of silicon under different etching treatments
are compared by using the photoelectromagnetic effect. A
measure of the minority carriers lifetime by the photoconductive
decay method provides another means of...
The selective masking effect of a thermally grown layer of silicon
dioxide has been widely utilized as a technique for controlling the
geometry and impurity concentration in semi-conductor device technology.
It is also recognized that the passivation of the silicon surface
by the vitreous silicon dioxide envelope protects the underlying...
The theoretical characteristics of space-charge-limited
currents in solids are reviewed, and a survey of
suitable dielectric materials and experimental space-charge-limited devices is presented.
The properties of the gold-silicon contact as used
in space-charge-limited devices were experimentally investigated.
It was found that the observed characteristics
could be explained on the basis...
The experimental procedure for reactively sputtering
films of silicon nitride together with the methods for
measuring the film thickness have been investigated.
Some of the properties of these nitride films were studied.
These properties included: infrared spectrum,
etching properties, and index of refraction. The adherence
of the films was also...
The properties of flash- evaporated films of GaAs
and GaP were studied in this investigation. Films were
grown at various substrate temperatures, source temperatures,
source-to-substrate distances and rates of deposition
and were evaluated as to their structural,
optical and electric properties.
It was found that substrate temperature was the
major...
This thesis investigates a way to fabricate P-N junctions by
percussive welding. The theoretical basis of percussive welding, design
considerations of the apparatus used, and the electrical characteristics
of the junctions were the main objectives of this investigation.
P-type silicon wafers and gold wire doped with arsenic as a
N-type...
Application of automatic production techniques to the fabrication
of semiconductor devices has been somewhat limited by the requirements
of conventional alloying techniques. These alloying techniques
require an excessive amount of individual handling.
This thesis investigates the feasibility of applying percussive
welding to the fabrication of metal-semiconductor contacts, as a
solution...
The force, temperature, and time relationships were
investigated by using oscilloscope measurement techniques. Force was measured using a strain gage and the dynamic
response recorded with a polaroid oscilloscope camera.
Temperature was measured with a tungsten-rhenium thermocouple
and recorded in the same manner. Residual stress
measurements were made to determine...
This paper is concerned with the determination of
gallium arsenide resistivity by measurement of attenuation of microwave energy at 7500 megacycles transmitted
through a slice.
The first section of this paper describes gallium
arsenide properties as compared to silicon, germanium,
silicon carbide, and diamond. A description is then
given of...
In this paper, the theory of metal-semiconductor contacts was
applied to metal contacts on gallium arsenide. A model was discussed
which proposed that the contact resistance was due to a highly
resistive region between the metal and the semiconductor. In order
to evaluate this resistance, a technique using a VHF...