Ion implantation of phosphorus (P) into 4H-SiC at room temperature and 500 degreesC was investigated. The P profiles simulated with a TRIM (transport of ions in matter) program showed good agreement with experimental results. The sheet resistance (R-S) of implanted layers at both temperatures decreased with increases in the annealing temperature between 1200 degreesC and 1600 degreesC. Also, in the case of the implanted layer at 500 degreesC, a low sheet resistance of 71 Omega/square was obtained by annealing at 1600 degreesC. Hot-implantation was found to greatly improve the carrier concentration obtained by Hall-effect measurements. In the case of annealing at 1700 degreesC, the R-S of implanted layers at both temperatures increased sharply. From AFM analysis, it is thought that the increase in R-S is due to the sublimation or evaporation of SiC from the surface of the implanted layer.