TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Method: The pre-cleaning step is carried out at 3-85 degrees C for 1-40 minutes using cleaning liquid including acid corrosion liquid or corrosive liquid. The doping method is liquid state diffusion, flaky diffusion, solid-solid diffusion, closed tube diffusion, gaseous diffusion or deposition diffusion. The doping method is carried out at temperature of 800-1050 degrees C for 5-120 minutes in doped protective atmosphere including argon, nitrogen, oxygen or air. The silicon sheet has surface doping depth of 0.1-15 mu m. The etching step is carried out for 1- 4 times using etching agent. The acid gas corrosion etching step is carried out at temperature of 0-30 degrees C for 1-20 minutes. The inorganic alkali corrosion etching is carried out at temperature of 20-85 degrees C for 5-40 minutes. The cleaning step is carried out using a cleaning solution including acid aqueous solution or alkali aqueous solution. The washing step is carried out at temperature 15-30 degrees C for 1-25 minutes. Preferred Components: The acidic corrosion liquid is mixed solution of 5-65 wt.% of nitric acid, 2-45 wt.% of hydrofluoric acid and water. The corrosive liquid is 0.5-30 wt.% of inorganic alkali aqueous solution. The inorganic alkali is ammonium hydroxide, lithium hydroxide, sodium hydroxide or potassium hydroxide. The surface is doped with phosphorus or boron surface dopant. The phosphorus surface dopant is phosphorus oxychloride, phosphorus trichloride, phosphorus tribromide, phosphoric acid, trimethyl phosphate, phosphorus pentoxide, phosphorus microcrystalline glass, phosphor silicon glass or phosphorus-containing silicon dioxide latex source. The boron surface dopant is boron trichloride, boron tribromide, boric acid, trimethyl borate, borate ester, boron oxide, boron nitride, boron glass ceramics, boron-containing silicon dioxide latex source or borosilicate glass. The acidic corrosion liquid is hydrofluoric acid, corrosion mixed solution of reagent or water. The etching agent is nitric acid, acetic acid, phosphoric acid, sulfuric acid or chromic acid. The corrosive liquid is 0.5-15 wt.% of inorganic alkali, isopropanol, sodium silicate, additive and etching aqueous solution. The silicon wafer has corrosion flocking quantity of 0.005-0.2 mg/cm2. The acidic solution is mixed solution of 2-10 wt.% of hydrochloric acid, 2-10 wt.% of hydrofluoric acid and water. The alkaline water solution is 0.5-15 wt.% of inorganic alkali aqueous solution.