A survey of the possible autocatalytic crystallization processes called explosive crystallization in liquid and solid states is given. The explosive liquid-phase epitaxy with laterally moving coupled interfaces of melting and crystallization in amorphous silicon layers on insulators is investigated by the use of an experimental equipment consisting of three synchronized lasers supplying the temperature pulses for ignition, spreading, and stopping of the explosive front. The velocity of this explosive crystallization front measured by use of time-resolved reflectivity of a test beam is compared with the results of model calculations. The results are in good agreement. The crystal structure was investigated by optical and transmission electron micrography and represents crystalline laminae grown preferentially in the 〈110〉 direction over a distance of about 100 μm. Areas of some millimeters in diameter can be crystallized by this method.

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A new type of p-channel CCD constructed on high-resistivity n-type silicon was exposed to 12 MeV protons at doses up to 1x10 11 protons/cm 2 . The charge transfer efficiency was measured as a function of radiation dose and temperature. We previously reported that these CCDs are significantly more tolerant to radiation damage than conventional n-channel devices. In the work reported here, we used pocket pumping techniques and charge transfer efficiency measurements to determine the identity and concentrations of radiation induced traps present in the damaged devices.

A single-beam thermowave technique is described, based on a two-frequency modulation of the laser beam used for both excitation and detection. The differential frequency content of the laser beam is used as a measure of the photothermal response. This technique provides frequency conversion to the low-frequency region and, to a certain degree, phase sensitivity without applying the lock-in detection method. By using a modulation set-up comprising two acousto-optical modulators and by applying a balance detector arrangement, an intermodulation content of 10-7 for zero response and a noise of 10-7 Hz-1/2 could be achieved. The new single-beam technique yields substantial evidence in the field of ion implantation and laser annealing of semiconductors, such as the dose of implanted species, annealing threshold, the defects generated by the ultrafast solidification and the homogeneity of the laser beam applied for irradiation.