METHOD FOR ETCHING NIOBIUM FILM

• Main Author: HIDAKA MUTSUO
• Format: Patent
• Language: English
• Published: 21.12.1989
• Subjects: BASIC ELECTRIC ELEMENTS; CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; DIFFUSION TREATMENT OF METALLIC MATERIAL; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; METALLURGY; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLICMATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASSC23 AND AT LEAST ONEPROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25; NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; SEMICONDUCTOR DEVICES

PURPOSE:To form a pattern with high accuracy of transfer without side etching by subjecting an Nb film on a substrate to reactive ion etching with a fluorine- contg. gas and keeping the substrate at a specified low temp. during the etching. CONSTITUTION:When an etching mask is set on an Nb film on a substrate 11 held between quartz plates 12 and the Nb film is subjected to reactive ion etching with a fluorine-contg. gas such as CF4, the substrate 11 is brought into contact with a water cooled electrode 14 through a copper plate 13 and kept at <=30 deg.C, preferably 0-30 deg.C by the electrode 14 during the etching. A reaction of F as neutral seed causing side etching is suppressed, an Nb film pattern having a perpendicular lateral face is obtd. and the accuracy of transfer of the pattern from the etching mask can be increased.