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The use of a DC glow discharge source with controlled plasma potential in plasma immersion ion implantation processing has been studied. The characteristics of the discharge source include medium densities, low temperatures, stable continuous DC operation and can be built inexpensively. A tridimensional implantation was realized when the plasma potential is held below 70 V. The plasma density of the discharge source has also been found to be linearly dependent on the potential.

Research was conducted to examine reciprocal space maps of PbTe/SnTe superlattices. To change the strain profile in the superlattices from completely pseudomorphic to partially relaxed, the individual layer thickness and number of repetitions were selected. Results demonstrate the importance of detailed structural characterization on the interpretation of electrical properties.

An examination of the electrical properties of Pb1-xSnxTe epitaxial layers with Sn composition covering the whole range was conducted. Samples were grown on (111) BaF2 substrates in a molecular beam epitaxy system by PbTe, SnTe and Te solid sources. As the alloy composition varies from PbTe to SnTe, the hole concentration increases exponentially from 10 (super 17) to 10 (super 20) cubic cm for Te-rich sources and from 10 (super 17) to 10 (super 19) cubic cm for stoichiometric ones.

Kinematical diffraction theory and optical coherence formation describe the X-ray diffraction in their layers having randomly placed defects. The diffracted intensity and the angular distribution are calculated by this method. Double crystal and triple crystal X-ray diffractometry experiments are also simulated by this method. Epitaxial ZnTe layers with mosaic structures are also investigated by using this method and by the application of different steps of chemical thinning.

Calculations using the dynamical theory of diffraction together with a sample model, which considers the segregation of indium atoms, are employed to fit the high-resolution x-ray spectra of strained InGaAs/GaAs quantum wells grown by molecular-beam epitaxy. The segregation coefficients obtained from the best fits to the experimental data of samples grown at different temperatures were in excellent agreement with the expected values and confirmed that x-ray diffraction was a valuable tool for the investigation of the segregation phenomenon.

Optical and electrical measurements were used to to study the bad inversion in the PbSnTe compound.

The characteristics of p-type CdTe epilayers grown by the hot-wall-beam epitaxy technique were investigated. The results showed that within the range p=4x10(super 14) to 2x10(super 18)cm(super -3), doping levels can be controlled. The hole concentration determined the Hall mobility. The growth rate was decreased while the incorporation of dopants was enhanced by photoassisted growth.

The p-type doping of PbTe with Ba[F.sub.2] is studied. The results have shown that a controlled p-type doping of PbTe with Ba[F.sub.2] is obtained up to [10.sup.19] [cm.sup.-3].

The strain and defect state of silicon implanted with nitrogen by plasma immersion ion implantation is examined using various spectroscopy methods. The close relationship between the calculated strain profiles and Auger electron spectroscopy (AES) nitrogen concentration profiles outside the amorphous regional signal has indicated interstitial nitrogen as the main source of strain.

An investigation is conducted on the electrical and optical characteristics of PbTe p-n junctions as a function of the electron concentration. Lead telluride mesa diodes were fabricated from a series of -n juctions in which the hole concentration p was kept constant and the electron concentration N varied.

The residual stress in diamond films grown on (001) silicon substrates, as a function of film thickness is determined using x-ray diffraction and micro-Raman spectroscopy. The type and magnitude obtained from these measurements agreed well for films thicker than 10 mu m and for films thinner than this value, and an opposite behavior between both results were seen, where this discrepancy was attributed to the domain size characteristic of each technique.

A series of Pb(sub 1-x)Eu(sub x) Te/PbTe multi-quantum well (MQW) samples were grown on (111) cleaved BaF2 substrate by molecular beam epitaxy. Using the in-plane lattice constant as the main fitting parameter, the strain in the PbTe well inside the MQW structure were obtained as a function of its width.