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Title: Method for etching thin films of niobium and niobium-containing compounds for preparing superconductive circuits

Abstract

An improved method of preparing thin film superconducting electrical circuits of niobium or niobium compounds in which a thin film of the niobium or niobium compound is applied to a nonconductive substrate, and covered with a layer of photosensitive material. The sensitive material is in turn covered with a circuit pattern exposed and developed to form a mask of the circuit in photoresistive material on the surface of the film. The unmasked excess niobium film is removed by contacting the substrate with an aqueous etching solution of nitric acid, sulfuric acid and hydrogen fluoride, which will rapidly etch the niobium compound without undercutting the photoresist. A modification of the etching solution will permit thin films to be lifted from the substrate without further etching.

Inventors:
 [1];  [2];  [2]
  1. Darien, IL
  2. Woodridge, IL
Issue Date:
Research Org.:
Argonne National Laboratory (ANL), Argonne, IL (United States)
OSTI Identifier:
863882
Patent Number(s):
4266008
Assignee:
United States of America as represented by United States (Washington, DC)
Patent Classifications (CPCs):
C - CHEMISTRY C23 - COATING METALLIC MATERIAL C23F - NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
method; etching; films; niobium; niobium-containing; compounds; preparing; superconductive; circuits; improved; film; superconducting; electrical; compound; applied; nonconductive; substrate; covered; layer; photosensitive; material; sensitive; circuit; pattern; exposed; developed; form; mask; photoresistive; surface; unmasked; excess; removed; contacting; aqueous; solution; nitric; acid; sulfuric; hydrogen; fluoride; rapidly; etch; undercutting; photoresist; modification; permit; lifted; resistive material; electrical circuits; containing compound; conductive substrate; improved method; nitric acid; sulfuric acid; electrical circuit; circuit pattern; containing compounds; sensitive material; superconducting electrical; photosensitive material; hydrogen fluoride; conducting electric; conductive circuit; /430/216/427/

Citation Formats

Kampwirth, Robert T, Schuller, Ivan K, and Falco, Charles M. Method for etching thin films of niobium and niobium-containing compounds for preparing superconductive circuits. United States: N. p., 1981. Web.
Kampwirth, Robert T, Schuller, Ivan K, & Falco, Charles M. Method for etching thin films of niobium and niobium-containing compounds for preparing superconductive circuits. United States.
Kampwirth, Robert T, Schuller, Ivan K, and Falco, Charles M. Thu . "Method for etching thin films of niobium and niobium-containing compounds for preparing superconductive circuits". United States. https://www.osti.gov/servlets/purl/863882.
@article{osti_863882,
title = {Method for etching thin films of niobium and niobium-containing compounds for preparing superconductive circuits},
author = {Kampwirth, Robert T and Schuller, Ivan K and Falco, Charles M},
abstractNote = {An improved method of preparing thin film superconducting electrical circuits of niobium or niobium compounds in which a thin film of the niobium or niobium compound is applied to a nonconductive substrate, and covered with a layer of photosensitive material. The sensitive material is in turn covered with a circuit pattern exposed and developed to form a mask of the circuit in photoresistive material on the surface of the film. The unmasked excess niobium film is removed by contacting the substrate with an aqueous etching solution of nitric acid, sulfuric acid and hydrogen fluoride, which will rapidly etch the niobium compound without undercutting the photoresist. A modification of the etching solution will permit thin films to be lifted from the substrate without further etching.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Jan 01 00:00:00 EST 1981},
month = {Thu Jan 01 00:00:00 EST 1981}
}