United States Patent 3,537,925
November 3, 1970

Method Of Forming A Fine Line Apertured Film
Arthur C. Chen

Filed March 14, 1967
Image of US PATENT 3,537,925

Abstract of the Disclosure

An apertured film having a line of narrow width, e.g., 3 microns, is produced by a process which includes the evaporation of a 2000 A. thick film of tin upon a glass substrate, the coating of the tin film with a layer of photoresist, and the partial removal of the photoresist adjacent the desired location of the lin e aperture to expose a portion of the underlying tin film. The partially masked tin film then is etched in a dilute solution of hydrochloric acid and nitric acid for a period of one second to dissolve the exposed tin film and undercut the photoresist by a distance of 3 microns. After a second 2000 A. thick layer of is deposited atop both the photoresist and partially uncovered substrate, the photoresist is softened by soaking the coated substrate in an organic solvent for approximately 3 minutes. The photoresist and that portion of the second layer of tin overlying the photoresist is subsequently removed by the low pressure spraying of the organic solvent upon the substrate thereby forming a fine line apertured film. When metal films having poor adhesion to the substrate are to be utilized to form the fine line apertured film, a seeding film such as nickel, tin, or chromium is deposited upon the substrate prior to the deposition of the metal films forming the fine line apertured film to improve the adhesion of the apertured film to the substrate
Figure descriptions: cover graphic

  • Figure 1 is a block diagram depicting the method of this invention.
  • Figure 2 is a portrayal of the sequential formation of the apertured film of this invention.
  • Figure 3 is a sectional view of a fine line apertured film having a seeding film intermediate the film and the substrate to increase the adhesion of the apertured film to the substrate.

 Citations [54]:
1,922,434 08/1933 Gundlach 3,210,226 10/1965 Young 3,438,873 04/1969 Schmidt
National Museum of American History
HomeSearchChip TalkChip FunPatentsPeoplePicturesCreditsCopyrightComments