The effect of time and temperature on the sheet resistance () and carrier concentration () of (100) P-type monocrystalline Si was investigated. Phosphorus-doped -emitters were fabricated through solid-source doping in a quartz tube furnace. The process variable values for 13 runs were proposed by response surface methodology (RSM). The optimized values for time and temperature predicted by RSM were 56 min and 1045°C, respectively, for a sheet resistance of and a carrier concentration of . Optimization-based fabrication was found to be in close agreement with the optimized values. Parameter optimization using RSM could be valuable in achieving predetermined dopant variables in optoelectronic devices as well as in reducing the surface recombinations and series resistance of highly efficient Si solar cells.