Substrates can undergo major temperature excursions during ion implantation if they are not well heat sunk. At power densities on the order of 50 watts per cm−2 radiatively cooled Si will melt in a matter of seconds. Such power densities can be maintained over a few sq. cms with many of the beams produced by even the moderate current machines currently used for doping Si and the III-V's. We have made use of this fact to study pulsed ion-beam annealing of implanted Si. Two types of studies have been carried out. In the first, 5–20 sec proton irradiations were done at power densities of 3–35 watts cm−2 to produce sample temperatures of 500 to 1100°C. 2×1016 cm−2 280 keV B, BF2 , As and P implants were annealed in this manner. Sheet resistances, ρs, versus power density curves were obtained for each ion and compared to psρs vs T data obtained for furnace annealed companion samples. In the second study the 2×1016cm−2 280 keV implants were carried out at progressively higher current densities so that the dopant beam itself raised the sample temperature to 500–1000°C. For each ion (other than B) it was possible to obtain power densities which resulted in self-annealing implants whose sheet resistances were as low as those obtained with the optimal furnace anneal. Details of the experiments, electrical and physical properties of the pulsed ion-beam annealed layers and device applications will be presented in this paper.