The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 21, 2004
Filed:
Jun. 21, 2002
Kenneth E. Knapp, Livermore, CA (US);
Ronald A. Barr, Mountain View, CA (US);
Lien-Chang Wang, Fremont, CA (US);
Benjamin P. Law, Fremont, CA (US);
James Spallas, Dublin, CA (US);
Western Digital (Fremont), Inc., Fremont, CA (US);
Abstract
The present invention provides an improved current perpendicular to the plane thin film read head device and method of fabrication. With the present invention, the lower lead is formed to inhibit accumulation of redeposited lead material on CPP sensor element side walls during CPP sensor formation. In the preferred embodiment, the upper portion of the lower lead, which normally is etched during sensor element formation, is formed of a low sputter yield material to reduce redeposition flux to the sensor side walls. It is also preferred to form the upper portion of a material that also has a low value for the ratio of its sputter yield at the lead milling angle-to-its sputter yield at the side wall milling angle to inhibit redeposition accumulation on the side wall. It is preferred to clad conventional lead material with a low sputter yield ratio, low resistivity material, to inhibit side wall redeposition accumulation while also providing a low resistance lower lead. The underlying lead material may be formed of conventional low resistance lead materials with a cladding of a refractory metal, such as tantalum, titanium, tungsten, molybdenum, zirconium, vanadium, niobium, their alloys, or the like. The improved CPP read head of the present invention may be embodied in a data storage and retrieval apparatus.