| 摘要 |
PURPOSE:To enable to perform a selective etching on n<+> amorphous silicon by a method wherein the etching compound solution, consisting of hydrofluoric acid, nitric acid and glacial acetic acid with the concentration of nitric acid of 0.15-0.65 in mixture ratio by volume and the concentration of hydrofluoric acid of below 0.04, is prepared. CONSTITUTION:In the case of etching compound solution consisting of hydrofluoric acid (46% aqueous solution), nitric acid (d=1.38, 60% aqueous solution, 14 normality) and glacial acetic acid, the concentration of nitric acid is to be at 0.15- 0.65 in the mixture ratio by volume and the concentration of hydrofluoric acid is to be below 0.04. The selective etching is performed on an n<+> amorphous silicon using the above solution. Accordingly, the thin film transistor with a glass substrate, a long-sized optical sensor and a thin film IC can be manufactured. |
