Three series of CoSi2 thin films which were fabricated by solid state reaction of evaporated Co, Ti/Co and Co/Ti on p-type Si (1 0 0) substrates with different annealing procedures, have been etched in a diluted hydrogen fluoride (0.5 wt.% HF) solution at 30 degreesC. The etching rate ranges from 0.08 to 0.36 nm/s and the induction period (a period in the beginning of the etching process when there is no change in the sheet resistance value) ranges from 48 to 660 s for all those samples. The CoSi2 films formed with a Ti capping layer depends on the annealing parameters more significantly than other two series. The induction period reduces dramatically, but does not eliminate, if a previous step of selective etching in the H2O2-H2SO4 solution and (or) the NH3-H2O2-H2O solution is performed. The surface roughness of the etched samples is monitored by atomic force microscopy (AFM) measurements.