| 摘要 |
PURPOSE: A low viscosity etching solution is provided to control etching rate in wide range, to maintain etching uniformity, and to reduce taper angle. CONSTITUTION: An etching solution not including hydroperoxide includes 5-40 wt% of sulfuric acid, 0.5-30 wt% of a nitric acid, 0.1-10 wt% of halogen additives, 0.5-20 wt% of an inorganic chelate agent, and residual water. The halogen additives are selected from HF, (NH4)F, (NH4)HF2, KF, NaF, MgF2, AlF3, HCl, (NH4)Cl, KCl, NaCl, MgCl2, FeCl3, AlCl3, HBr, (NH4)Br, KBr, NaBr, MgBr2, AlBr3, HI, (NH4)I, KI, NaI, MgI2, and A1I3. |
