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Formation of Mo/Si contacts by implantation of phosphorus ions was studied. The implantation was carried out at temperatures of −196, 25, and 150 °C and a fluence ranging between 1015 and 1017 ions cm−2. The morphological and structural characterizations were done with scanning electron microscopy, transmission electron microscopy, and x‐ray diffraction. Hexagonal MoSi2 phase was identified in samples implanted with more than 1016 ions cm−2 at all three implantation temperatures. Traces of MoP were found in the sample implanted with 1017 ions cm−2 at 150 °C. Measured effective contact resistance showed ohmic behavior in as‐implanted samples except for samples implanted with 1015 ions cm−2 at 150 °C. Smooth surfaces of implanted MoSi2 structures remained after post‐implant annealing at 850 °C for 1/2 h in H2 ambient. The effect of post‐implant annealing is also discussed in terms of doping, microstucture, and contact resistance.

Solid phase regrowth of Si on sapphire has been investigated in the Si (amorphous)/Al (poly)/Al2O3 (crystal) system. Using transmission electron microscopy, scanning electron microscopy, Auger electron spectroscopy, and Hall‐effect measurements, it has been shown that Si is transported through an Al film at 550 °C to produce p‐type Si films on the sapphire substrate. The growth process has been shown to be initiated at Si nucleation sites on the substrate. These sites expand by mass accretion, forming island structures that coalesce to yield continuous large grained polycrystalline Si films on the sapphire surface.Solid phase regrowth of Si on sapphire has been investigated in the Si (amorphous)/Al (poly)/Al2O3 (crystal) system. Using transmission electron microscopy, scanning electron microscopy, Auger electron spectroscopy, and Hall‐effect measurements, it has been shown that Si is transported through an Al film at 550 °C to produce p‐type Si films on the sapphire substrate. The growth process has been shown to be initiated at Si nucleation sites on the substrate. These sites expand by mass accretion, forming island structures that coalesce to yield continuous large grained polycrystalline Si films on the sapphire surface.

Amorphous silicon has been produced on a single‐crystal silicon surface that was exposed to intense pulsed UV‐laser radiation at 266 nm. In addition, the formation of an oxide several tens of nanometers in thickness is observed when the irradiation takes place in an O2 or in an air ambient. Various experimental techniques including transmission electron microscopy, sputtered Auger electron spectroscopy, and differential Fourier‐transform IR spectroscopy have been employed to characterize the laser‐induced amorphous silicon and the oxide layer formed by this rapid melting and resolidification process. The present study suggests a new oxidation phenomena, namely, ’’laser‐induced oxidation.’’

Q‐switched laser irradiation has been used to anneal O+‐implanted silicon to form SiO2 layers. Results of differential Fourier‐transformed infrared spectroscopy and transmission electron microscopy confirm the formation of oxide layers. Segregation of oxygen toward the surface was observed by secondary ion mass spectroscopy and correlated with resolidification velocities, which vary as a function of laser energy densities.