US 9,810,748 B2
Tunneling magneto-resistor device for sensing a magnetic field
Keng-Ming Kuo, Yunlin County (TW); and Ding-Yeong Wang, Hsinchu County (TW)
Assigned to Industrial Technology Research Institute, Hsinchu (TW)
Filed by Industrial Technology Research Institute, Hsinchu (TW)
Filed on Dec. 11, 2015, as Appl. No. 14/967,235.
Claims priority of application No. 104110195 A (TW), filed on Mar. 30, 2015.
Prior Publication US 2016/0291097 A1, Oct. 6, 2016
Int. Cl. G01R 33/09 (2006.01)
CPC G01R 33/098 (2013.01) 11 Claims
OG exemplary drawing
 
1. A tunneling magneto-resistor device for sensing magnetic fields, comprising:
a first TMR (tunneling magneto-resistor) sensor comprising a first and a second MTJ (magnetic tunneling junction) device connected in parallel, each of the first and second MTJ device having a pinned layer and a free layer;
a second TMR sensor comprising a third and a fourth MTJ device connected in parallel, each of the third and fourth MTJ device having a pinned layer and a free layer;
a third TMR sensor comprising a fifth and a sixth MTJ device connected in parallel, each of the fifth and sixth MTJ device having a pinned layer and a free layer;
a fourth TMR sensor comprising a seventh and an eighth MTJ device connected in parallel, each of the seventh and eighth MTJ device having a pinned layer and a free layer;
wherein each of the pinned layers of the first and second MTJ devices has a pinned magnetization at a first pinned direction; the free layer of the first MTJ device has a first free magnetization parallel to a first easy-axis and the free layer of the second MTJ device has a second free magnetization anti-parallel to the first easy-axis;
wherein first terminals of the first and fourth TMR sensors are connected to a first voltage node; first terminals of the third and second TMR sensors are connected to a second voltage node; second terminals of the first and third TMR sensors are connected together, and second terminals of the second and fourth TMR sensors are connected together;
wherein each of the pinned layers of the third and fourth MTJ devices has a pinned magnetization at the first pinned direction; the free layer of the third MTJ device has a third free magnetization parallel to the first easy-axis and the free layer of the fourth MTJ device has a fourth free magnetization anti-parallel to the first easy-axis;
wherein the first free magnetization and the pinned magnetization of the first MTJ device have a first angle of α degrees therebetween; the third free magnetization and the pinned magnetization of the third MTJ device have the first angle of α degrees therebetween; the second free magnetization and the pinned magnetization of the second MTJ device have an second angle of π-α degrees therebetween; the fourth free magnetization and the pinned magnetization of the fourth MTJ device have the second angle of π-α degrees therebetween; and α is not zero.