Patent ID: 7193891
Filing Date: 2007-03-20
Classification: G01R,G11B,G11C,H01L,H03K

Abstract:
1. A magnetic field sensor device comprising: a first ferromagnetic region having a first fixed magnetization state and characterized by a first coercivity; a first enhancement region coupled to said first ferromagnetic region, which enhancement region is adapted to increase a polarization efficiency for a spin polarized current; a second ferromagnetic region characterized by a second coercivity smaller than said first coercivity, and which second ferromagnetic region has a second magnetization state which is configured to respond to a magnetic field generated by magnetic data; a second enhancement region coupled to said second ferromagnetic region, which second enhancement region is also adapted to increase a polarization efficiency for a spin polarized current; wherein the sensor device has a variable magnetic resistance based on a relationship between said first magnetization state of said first ferromagnetic region and said second magnetization state of said second ferromagnetic region such that a value of a spin polarized current conducted in the sensor device varies in accordance with said magnetic data.