Thin film techniques for fabricating narrow track ferrite heads
Patent 4375390 Issued on March 1, 1983. Estimated Expiration Date: 
March 15, 2002. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
March 15, 2002. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 3808108 Semiconductor pattern delineation by sputter etching process Fabrication of multi-level relief patterns in a substrate Method for forming a narrow dimensioned region on a body Method for producing disk-recording plates Process and mask for ion beam etching of fine patterns Patent #: 4275286 Inventors
ApplicationNo. 06/357947 filed on 03/15/1982US Classes:204/192.32, Sputter etching216/22, FORMING OR TREATING ARTICLE CONTAINING MAGNETICALLY RESPONSIVE MATERIAL216/48, Mask is exposed to nonimaging radiation216/66, Using ion beam, ultraviolet, or visible light216/75Substrate contains elemental metal, alloy thereof, or metal compoundExaminersPrimary: Demers, Arthur P.International ClassesG03F 7/00 (20060101)G11B 5/193 (20060101) H01F 41/00 (20060101) H01F 41/34 (20060101) AbstractA process for producing a reactive ion-etched structure with height and width dimensions of the order of 25 microns or less on a ferrite substrate surface is disclosed. A mask of positive water saturated photoresist is formed on the substrate. A metal taken from the group consisting of nickel and a nickel-iron alloy is plated through the mask. The photoresist mask is removed to leave a pattern in the plated metal. The ferrite substrate surface that is exposed by the pattern is reactive ion etched with a power density of >1w/cm2 and a bias voltage <-100 volts.Other References
|
| ||||||||||||||
