0.4-μm-thick polycrystalline silicon deposited in a low-pressure CVD reactor was implanted with B to a dose of 5×1014/cm2 and then irradiated in a cw laser scanning apparatus. The laser annealing produced an increase in grain size from ∼500 Å to long narrow crystals of the order of ∼25×2 μ, as observed by TEM. Each grain was found to be defect free and extended all the way to the underlying Si3N4. Electrical measurements show 100% doping activity with a Hall mobility of about 45 cm2/V sec, which is close to single-crystal mobility at the same carrier concentration. Thermal annealing produces material with an average grain size of 1000 Å and a resistivity higher by a factor of 2.2 than that obtained with the laser anneal. Laser annealing performed after a thermal anneal reduces the resistivity to approximately the same value obtained by laser annealing only.

Complete electrical activity was obtained by cw laser annealing of 7×1015 As/cm2 implanted into (100) Si at 100 keV. The peak concentration for these implantation conditions is 1.4×1021/cm3, both theoretically and experimentally. However, this peak concentration was found to be thermally unstable, relaxing to a value of 3×1020/cm3 in a period of less than 2 min at 900 °C. If the peak implanted concentration is below 3×1020/cm3, the electrical activation and crystal structure are unaffected by similar thermal processing. We conclude from these data that the solid solubility of As in Si at 900 °C is approximately 3×1020/cm3, which is almost an order of magnitude below the published value.

The correlation observed in CdTe between microscopic defects and the infrared absorption at 10.6 μm is reported. The data were obtained from transmission electron microscopy, scanning electron microscopy, infrared and optical microscopy, spectrophotometry, and laser calorimetry. For chlorine and indium doped samples it was determined that increasing the concentrations of In2Te3 and CdCl2 precipitate platelets subsequently increases the 10.6 μm infrared absorption coefficient in CdTe. Isolated dislocations, dislocation networks, tellurium precipitates, vacancy loops, and stacking faults were also shown to exercise an important influence on infrared absorption. Localized regions of defect aggregations in many samples were found to be responsible for the macroscopicabsorption sites typically observed by infrared microscopy. The significant differences between the present data and previously reported macroscopic defect models are discussed.

Mean lives of the 4 + to (12 + ) yrast states in 72 Se populated in the reaction 58 Ni( 16 0, 2p) were extracted from a line-shape analysis of the Doppler-broadened lines. The results strongly support the interpretation of the crossing of states built on near-spherical and deformed shapes in the yrast cascade. A least-squares fit of a collective Hamiltonian to the experimental data yielded a potential energy surface with spherical and strongly deformed prolate minima.