A magnetoresistive effect sensor uses a shielded-type magnetoresistive effect
element
using a magnetoresistive effect film formed by a basic configuration of a combination
of a free layer, a barrier layer formed on the free layer, and a fixed layer formed
on the barrier layer, wherein a sensing current flows substantially perpendicular
to the magnetoresistive effect film, and wherein an amorphous material or a microcrystalline
material is used in a lower shield.
