Verfahren zum Herstellen von scharf definierten Aperturen in einer isolierenden Schicht bzw.in Halbleitermaterial,insbesondere zur gegenseitigen elektrischen Isolierung verschiedener in einer integrierten oder monolithischen Halbleitervorrichtung zusammengefasster Schaltungselemente

摘要

1,084,003. Etching. INTERNATIONAL BUSINESS MACHINES CORPORATION June 7, 1966 [June 24, 1965], No. 25228/66. Heading B6J. [Also in Division H1] A method of forming an aperture in a layer of electrically insulating material (e.g. a layer of glass on a substrate of silicon semi-conductor material) comprises removing part of a metal layer formed on the insulating layer (e.g. a chromium layer overlaid by a copper layer, removed by etching after application, exposure and development of a photo-sensitive resist), forming a layer of masking material (e.g. silicon monoxide) on the remaining metal and the exposed surface of the insulating layer, removing the remaining metal and its overlying masking material to expose the insulating layer, and etching the exposed surface of the insulating layer. Chromium is removed with potassium ferricyanide and caustic soda. The silicon substrate can also be etched with silver nitrate, nitric acid and hydrofluoric acid.