US 12,243,565 B2
Dual free layer read head having recessed sidewall insulator layer and method of making thereof
Chih-Ching Hu, Pleasanton, CA (US); Yung-Hung Wang, San Jose, CA (US); Ming Mao, Dublin, CA (US); Ming Jiang, San Jose, CA (US); Yukimasa Okada, Cupertino, CA (US); and Goncalo Baiao de Albuquerque, San Jose, CA (US)
Assigned to Western Digital Technologies, Inc., San Jose, CA (US)
Filed by WESTERN DIGITAL TECHNOLOGIES, INC., San Jose, CA (US)
Filed on Aug. 14, 2023, as Appl. No. 18/233,800.
Claims priority of provisional application 63/506,180, filed on Jun. 5, 2023.
Prior Publication US 2024/0404552 A1, Dec. 5, 2024
Int. Cl. G11B 5/39 (2006.01)
CPC G11B 5/3909 (2013.01) [G11B 5/3945 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A magnetic recording head comprising a first reader, wherein the first reader comprises:
a first lower shield;
a first dual free layer (DFL) sensor located over the first lower shield and comprising a first free layer, a second free layer and a first barrier layer located between the first free layer and the second free layer;
a first upper shield located over the first DFL sensor;
a first synthetic antiferromagnetic (SAF) structure located adjacent to a first side of the first DFL sensor, the first SAF structure comprising a first lower soft bias layer, a first upper soft bias layer, and a first spacer layer located between the first lower soft bias layer and the first upper soft bias layer; and
a first sidewall insulating layer comprising a first portion having a first thickness located between the first lower soft bias layer and the first free layer, wherein:
the first upper soft bias layer is in direct contact with a first sidewall of the second free layer; or
a second portion of the first sidewall insulating layer having a second thickness less than the first thickness is located between the first sidewall of the first upper soft bias layer and the second free layer.