Patent ID: 7916434
Filing Date: 2011-03-29
Classification: B82Y,G11B,H01F,H01L

Abstract:
1. A tunnel magnetoresistive effect element comprising: a tunnel barrier layer formed primarily of a metal oxide; and two ferromagnetic layers stacked so as to sandwich said tunnel barrier layer, said tunnel barrier layer including many electric charge sites which cause electric popping noise, the electric popping noise being separated and distinguished, by setting said tunnel magnetoresistive effect element to be magnetically saturated, from a popping noise caused by a magnetization state of the element, electric popping output voltage, which is a maximum absolute voltage of peaks and valleys of said electric popping noise, being provided when a bias voltage is applied for a predetermined measuring time in a direction perpendicular to a surface of said tunnel barrier layer with said tunnel magnetoresistive effect element magnetically saturated, and a density of said electric charge sites in said tunnel barrier layer being controlled by limiting said electric popping output voltage so that ΔV where ΔV p is a value of said electric popping output voltage and ΔV s is a value of element output voltage, the element output voltage being defined as a difference between maximum and minimum values of resistance during reading of said tunnel magnetoresistive effect element.