NOVELTY - A silicon wafer etching solution comprises 0.5-1 pt. wt. sodium hydroxide, 0.5-1 pt. wt. borax, 3-5 pts. wt. additives, 0.3-0.5 pt. wt. cocoyl glycine potassium, 0.3-0.5 pt. wt. polyvinylpyrrolidone, 0.1-0.2 pt. wt. sodium stearate, 0.1-0.2 pt. wt. octyl phenol ethoxylates, 0.5-1 pt. wt. trioctanoin and 80-100 pts. wt. water. The additive comprises 10-15 pts. wt. saponin, 0.1-0.15 pt. wt. titanium dioxide, 0.1-0.2 pt. wt. ammonium persulfate, 1-1.5 pts. wt. vinyl acetate, 0.2-0.4 pt. wt. sodium bicarbonate, 1-2 pts. wt. lauryl glucoside and 100-150 pts. wt. water.    USE - Single crystal silicon wafer etching solution for removing oil and wax, used in manufacture of solar energy battery.    ADVANTAGE - The solution performs etching process with consistency and repeatability, increased pile density, and increases solar energy battery efficiency, improves product quality, has excellent wax and oil removing performance, removes finger print stain, excellent treatment effect, and is environmentally-friendly and promotes human health.    DETAILED DESCRIPTION - A silicon wafer etching solution comprises 0.5-1 pt. wt. sodium hydroxide, 0.5-1 pt. wt. borax, 3-5 pts. wt. additives, 0.3-0.5 pt. wt. cocoyl glycine potassium, 0.3-0.5 pt. wt. polyvinylpyrrolidone, 0.1-0.2 pt. wt. sodium stearate, 0.1-0.2 pt. wt. octyl phenol ethoxylates, 0.5-1 pt. wt. trioctanoin and 80-100 pts. wt. water. The additive comprises 10-15 pts. wt. saponin, 0.1-0.15 pt. wt. titanium dioxide, 0.1-0.2 pt. wt. ammonium persulfate, 1-1.5 pts. wt. vinyl acetate, 0.2-0.4 pt. wt. sodium bicarbonate, 1-2 pts. wt. lauryl glucoside and 100-150 pts. wt. water. The additive is prepared by grinding saponins, adding saponin powder, sodium bicarbonate, lauryl glucoside to water at 70-80 degrees C, stirring at 200-400 rpm for 4-6 hours, cooling, filtering, adding vinyl acetate and titanium dioxide to filtrate, ultrasonically dispersing for 5-10 minutes, adding 2-5% solution of ammonium persulfate at 70-80 degrees C for 1-2 hours, cooling and filtering. An INDEPENDENT CLAIM is included for preparation of single crystal silicon wafer etching solution, which involves (1) adding cocoyl glycine potassium and octyl phenol polyoxyethylene ether with 1/3-1/2 by weight of water, stirring for 400-600 rpm for 5-10 minutes, adding trioctanoin and sodium stearate at 70-80 degrees C, stirring at 800-1000 rpm for 10-20 minutes, cooling to obtain component (A), (2) dissolving sodium hydroxide in remaining amount of water, adding remaining raw materials at 40-60 degrees C, stirring at 200-400 rpm for 2-4 hours, obtaining component (B), mixing components (A) and (B) at 70-80 degrees C, and stirring at 1000-1500 rpm for 10-15 minutes.