| 摘要 |
PURPOSE:To prevent disconnection of metal wirings to be formed through opening parts of a semiconductor device by a method wherein taper of the sides of the opening parts to be formed in an oxide film on the surface of a semiconductor substate is made regulatable. CONSTITUTION:The field oxide film 13 is formed on the surface of the semiconductor substrate 11 having the semiconductor regions 12-1, 12-2 formed by the impurity diffusion method, etc. A photo resist 15 is applied on the surface of the film 13 interposing an adhesion improver 14 between them. A pattern is formed with the two layers theref to expose the prescribed surface parts 16 of the film 13. The exposed films 13 thereof are dipt for the prescribed hours in a predip liquid to weaken the function of the adhesion improver 14. Accordingly the surface of the film 13 is changed from the oiliness to the hydrophilic property. The exposed films 13 are etched using a mixed liquid consisting of an ammonium fluoride and hydrochloric acid having the prescribed volumetric ratio to form the opening parts 17-1-17-3 having the prescribed taper in the film 13. Moreover oxide films 18 are formed on the exposed faces of the substrate 11, and contact holes 19-1, 19-2 are formed at the prescribed places of the films 18 by the same method. |
