Planar design for sensors in a dual free layer read head

US11514934B1 · kind B1 · utility

Assignee

• Western Digital Technologies, Inc. · US

Inventors

• Ming Mao · Pleasanton, US
• Chen-Jung Chien · Mountain View, US
• Daniele Mauri · San Jose, US
• Goncalo Marcos BAIÃO DE ALBUQUERQUE · San Jose, US
• Chih-Ching Hu · Pleasanton, US
• Anup G. Roy · Fremont, US
• Yung-Hung Wang · San Jose, US

Key dates

• Filing date: Oct 27, 2021
• Grant date: Nov 29, 2022
• Expiry date: Oct 27, 2041

Classification

• Technology area (CPC G): Physics
• CPC primary: G11B2005/3996
• WIPO field: Audio-visual technology
• WIPO sector: Electrical engineering

Abstract

The present disclosure generally relates to a dual free layer (DFL) two dimensional magnetic recording (TDMR) read head. The read head comprises a first sensor, a first rear hard bias (RHB) structure disposed adjacent to the first sensor, an upper shield disposed over the first sensor and first RHB structure, a lower shield disposed over the upper shield, a second sensor disposed over the lower shield, and a second RHB structure disposed adjacent to the second sensor. A first surface of the first sensor is substantially flush or aligned with a first surface of the first RHB structure. A first surface of the second sensor is substantially flush or aligned with a first surface of the second RHB structure. The upper shield extends linearly from a media facing surface into the read head. The first lower shield is over-milled a greater amount of time than the second lower shield.