The micro-structural and electrical properties of Al implanted 4H-SiC annealed using a halogen lamp furnace has been investigated. A significant improvement in the surface morphology, sheet resistance, and pn leakage currents were observed. However, a relatively high density of dislocation loops were observed for the lamp annealed samples. These micro-structural defects composed of clustered interstitial atoms residing on basal planes show a strong dependence on the annealing time. No correlation between the dislocation loop density and size on the pn junction leakage current was observed for the lamp annealed 4H-SiC. The possible formation kinetics of the micro-structural defects are discussed.