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Research was conducted to examine the electronic characteristics and isochronal annealing behavior of defects formed in epitaxially grown n-Si by 1 keV He, Ne- and Ar-ion bombardment using deep level transient spectroscopy. Two families of related defects were seen in the unannealed samples. Results indicate that most of the defects introduced by the low energy noble gas ions are different from the primary defects created by 5.4 MeV alpha-particle irradiation.

Free-carrier concentration changes in n-GaAs after it was processed in He plasma were studied using capacitance-voltage measurements. In addition, the electrical characteristics of the plasma-induced defects were examined. Results showed that a strong carrier reduction of up to 1 micron meter below the GaAs surface occurred following the He-plasma processing. He-plasma processing was also observed to control the fabrication of high barrier Schottky diodes on n-GaAs.

The use of deep level transient spectroscopy (DLTS) helps determine the electrical characteristics of defects developed during irradiation of undoped epitaxially grown GaAs by neutrons from a clinical source. GaAs with reduced free carrier concentration are used so that the influence of the electric field on emission characteristics is minimal. Analysis of the characteristics of electron traps En1, En2, En4 and En5 reveals En5 to be the major defect with an energy level of Ec-0.66 electron volts and En1, En2 and En4 are of a point defect nature.

Standard current-voltage measurements were used to investigate the effect of electron beam evaporation rate of Pt and the semiconductor carrier density on the characteristics of Pt/n-GaAs Schottky contacts. The results showed that shielding of the GaAs during Pt deposition resulted in high quality Schottky barrier diodes. Metallization without any electron shield resulted in several surface and subsurface defects.

Provides information on an experiment investigating the electric and annealing properties, determined by deep level transient spectroscopy (DLTS) of defects introduced in epitaxially grown n-Si during low energy (1 keV) He-ion bombardment. Methodology used to conduct the experiment; How the main defects introduced were derived; What was proposed about the defeects introduced; Results of the experiment.

A low-cost, spark-erosion cutter for stain-free cutting of conducting materials in samples of specific shapes, has been built. A servo system monitors the distance between tool and sample, and advances the tool towards the sample when necessary in a controlled way. Advancement rates of between 0.4 and 3.0 mm/h are presently used but with other gear ratios for the motor it could be changed to almost any practical value. Cutting rates of typically 1–1.5 mm/h are used. The cutter works quite well, is within the financial reach of smaller laboratories, and can be built in a local machine shop. [ABSTRACT FROM AUTHOR]

Examines the electrical and morphological properties of ruthenium-gold (Ru/Au) ohmic contact system grown on gallium arsenide substrates. Details on the surface morphology of Ru/Au contact system; Details on the thermal stability and specific contact resistance of Ru; Application of Ru contacts to heterojunction bipolar transistors and solid state lasers.

Examines the annealing characteristics and thermal stability of electron beam evaporated ruthenium (Ru) and n-gallium arsenide (n-GaAs) Schottky diode contacts. Fabrication of Ru Schottky diodes on n-GaAs; Influence of annealing temperature on effective and flatband barrier heights; Effect of atmospheric exposure of Ru/GaAs contact on diode properties.

Examines the electrical properties of defects introduced in n-gallium arsenide (GaAs) layers during dry etching in a silicon tetrachloride plasma. Use of deep-level transient spectroscopy to determine the electrical properties; Characteristics of the plasma introduced defects; Fabrication of Schottky barrier diodes on plasma etched n-GaAs surfaces.

Scandium (Sc) Schottky barrier diodes were fabricated by electron-beam (EB) deposition on epitaxially grown p-Si[sub 1-χ]Ge[sub χ] strained films with χ = 0.0-0.2. The EB deposition was performed either with or without shielding the Si[sub 1-χ]Ge[sub χ] samples. The barrier height and the defects introduced during EB deposition have been investigated as a function of Ge composition. Our results showed that the barrier height decreased as the band gap changed with increasing Ge content. The defect properties were studied with deep-level transient spectroscopy. The most prominent defect observed in p-Si was a hole trap H(0.53) at E[sub v] + 0.53 eV. Increasing the Ge content led to a decrease in the activation energy of this defect and this decrease followed the same trend as the band-gap variation, suggesting that the main defect detected in p-Si[sub 1-χ]Ge[sub χ] is the same as that observed in p-Si. [ABSTRACT FROM AUTHOR]

This note describes the design, construction, and test results of a modified sample holder used during low-temperature deep-level transient spectroscopy, current-voltage and capacitance-voltage measurements. This improved sample holder allows temperature scan rates of up to 6 K/min with a temperature shift of less than 1 K. High electrical isolation makes this sample holder also suitable for low-temperature current-voltage and capacitance-voltage measurements. [ABSTRACT FROM AUTHOR]