Current-perpendicular-to-plane magnetoresistance effect device with double current control layers

A magnetic reproducing apparatus which reads magnetic information recorded on a magnetic recording medium by use of a magnetic head including a magnetoresistance effect element of the dual spin valve type using a current-perpendicular-to-the-plane (CPP) system where a sensing current flows perpendicular to the stacked faces of a plurality of conductive layers, the magnetoresistance effect element comprising:

• a first unit which includes a free layer;
• and
• a second unit which includes the free layer shared with the first unit;
• the first unit including:
• a first upper nonmagnetic intermediate layer;
• a second upper nonmagnetic intermediate layer;
• and
• a first current control layer which limits the flow quantity of the sensing current and is sandwiched between the first and second upper nonmagnetic intermediate layers;
• the second unit including:
• a pinning layer;
• a first lower nonmagnetic intermediate layer;
• a second lower nonmagnetic intermediate layer;
• and
• a second current control layer which limits the flow quantity of the sensing current and is sandwiched between the first and second lower nonmagnetic intermediate layers;
• the first current control layer including:
• an insulating material which insulates the first and second upper nonmagnetic intermediate layers from each other electrically, and
• a conductive material which is formed in the insulating material in a distributed manner and which connects the first and second upper nonmagnetic intermediate layers to each other electrically so as to permit the sensing current to pass through the insulating material in a confining fashion;
• and
• the second current control layer including:
• an insulating material which insulates the first and second lower nonmagnetic intermediate layers from each other electrically, and
• a conductive material which is formed in the insulating material in a distributed manner and which connects the first and second lower nonmagnetic intermediate layers to each other electrically so as to permit the sensing current to pass through the insulating material in a confining fashion.