TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The metal-activated selective oxidation comprises using an aqueous solution containing an oxidant and a metal salt, where the oxidant comprises persulfate ion, permanganate ion and/or bichromate ion. The aqueous solution used in the metal-activated selective oxidation comprises sodium persulfate and silver nitrate, where a molar ratio of sodium persulfate to silver nitrate is 2:1-150:1, and a duration time of the metal-activated selective oxidation is 5-10 minutes. The dopant comprises phosphorus oxychloride.    TECHNOLOGY FOCUS - INSTRUMENTATION AND TESTING - Preferred Method: The dry surface treatment comprises an atmospheric pressure plasma jet (AAPJ) treatment or a laser treatment. The AAPJ treatment uses nitrogen or clean dry air, where a radio frequency power of the AAPJ treatment is 250-800 W. In the method, a processing rate of the AAPJ treatment is 20-200 mm/second, a width of a plasma beam in the AAPJ treatment is 2-4 mm, a processing time of the AAPJ treatment is 20-240 seconds, a distance between the plasma beam in the AAPJ treatment and the silicon substrate is 5-30 mm, and neodymium:yttrium-aluminum-garnet laser is adopted in the laser treatment, where a laser power of the laser treatment is 1-20 W, a processing time of the laser treatment is 0.1-1 milliseconds, and a laser processing dot pitch of the laser treatment is 100-1000 mu m. The saw damage removal process comprises using a solution containing hydrofluoric acid, nitric acid, and hydrogen peroxide. The method further comprises rinsing the silicon substrate with a nitric acid solution or with a solution containing potassium hydroxide, after forming the nanotexturized surface and before performing the dopant diffusion process. The aqueous solution for etching the irregular surface contains hydrofluoric acid and hydrogen peroxide, where a molar ratio of hydrofluoric acid to hydrogen peroxide to water in the aqueous solution is 1:1:10-3:1:30, and a duration time for etching the irregular surface is 5-10 minutes. In the method, of forming the anti-reflection layer comprises a physical vapor deposition process and of forming the electrode comprises a screen printing process and a sintering process. EXAMPLE - Solution of hydrogen fluoride, nitric acid and water of volume ratio 2:7:1 were adopted to etch a silicon substrate for 3 minutes at 10 degrees C, and saw damage removal was performed. The silicon substrate was processed with an atmospheric pressure plasma jet (AAPJ) treatment to have an irregular surface (where the parameters in the AAPJ treatment were: gas was processed with nitrogen; radio frequency power (13.56 MHz); processing rate (150 mm/second); processing time (30 second); width of plasma beam (3 mm); and distance between plasma beam and silicon substrate (1 cm)). The silicon substrate was placed into a solution of sodium persulfate (0.1 M) and silver nitrate (0.1 M) (with a volume ratio of 2:1) under mild agitation to carry out the metal-activated selective oxidation. The entire metal-activated selective oxidation was completed in 5-10 minutes. The silicon substrate was then rinsed with deionized water and dried in nitrogen flow. The silicon substrate after the selective oxidation was placed in aqueous solution containing hydrogen fluoride and hydrogen peroxide of volume ratio 1:5:10, etched for 5-10 minutes, rinsed with deionized water and dried in the nitrogen flow. Then the silicon substrate was dipped in a potassium hydroxide and water solution of volume ratio 1:50 for removing the nano-porous silicon layer formed. The concentrated nitric acid solution may be optionally used to remove the remaining silver, and the silicon substrate was then rinsed with deionized water and the silicon substrate was further subjected to processes including phosphorus diffusion, anti-reflection layer deposition and electrode formation, to give the fabrication of the solar cell.