TY - JOUR
T1 - Temperature dependence of electrical transport and magnetization reversal in magnetic tunnel junction
AU - Chao, Chien Tu
AU - Chen, Che Chin
AU - Kuo, Cheng Yi
AU - Wu, Cen-Shawn
AU - Horng, Lance
AU - Isogami, Shinji
AU - Tsunoda, Masakiyo
AU - Takahashi, Migaku
AU - Wu, Jong-Ching
PY - 2010/6/1
Y1 - 2010/6/1
N2 - A series of tunneling magnetoresistance (TMR) has been measured at various temperatures ranging from 4 K to 360 K for characterizing the electrical transport and magnetization reversal of nanostructured magnetic tunnel junctions (MTJs) with thin effective MgO barrier of 1 nm thickness and resistance-area (RA) product of 10 Ω μm2. MTJs with 150 × 250 nm 2 elliptical shape were fabricated by using electron beam lithography in combination with ion beam milling. Typical TMR curves were observed at temperature above 70 K, below which there was no significant anti-parallel (AP) state revealed. A linear relationship is found between resistance and temperature in both parallel (P) and AP states, having linear coefficients of - 4.15 × 10-4 and - 8.07 × 10-4 (Ω/K), respectively. The TMR ratio was found to be proportional to 1-BT3/2. The negative temperature coefficients and TMR tendency with temperature indicated that electrical transport is dominated mainly by tunneling mechanism. In addition, the biasing field of pinned CoFeB layer due to RKKY coupling increased with decreasing temperature until a maximum biasing field reached at 200 K, after which the biasing field decreased with decreasing temperature.
AB - A series of tunneling magnetoresistance (TMR) has been measured at various temperatures ranging from 4 K to 360 K for characterizing the electrical transport and magnetization reversal of nanostructured magnetic tunnel junctions (MTJs) with thin effective MgO barrier of 1 nm thickness and resistance-area (RA) product of 10 Ω μm2. MTJs with 150 × 250 nm 2 elliptical shape were fabricated by using electron beam lithography in combination with ion beam milling. Typical TMR curves were observed at temperature above 70 K, below which there was no significant anti-parallel (AP) state revealed. A linear relationship is found between resistance and temperature in both parallel (P) and AP states, having linear coefficients of - 4.15 × 10-4 and - 8.07 × 10-4 (Ω/K), respectively. The TMR ratio was found to be proportional to 1-BT3/2. The negative temperature coefficients and TMR tendency with temperature indicated that electrical transport is dominated mainly by tunneling mechanism. In addition, the biasing field of pinned CoFeB layer due to RKKY coupling increased with decreasing temperature until a maximum biasing field reached at 200 K, after which the biasing field decreased with decreasing temperature.
UR - http://www.scopus.com/inward/record.url?scp=77952848732&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=77952848732&partnerID=8YFLogxK
U2 - 10.1109/TMAG.2010.2045354
DO - 10.1109/TMAG.2010.2045354
M3 - Article
AN - SCOPUS:77952848732
VL - 46
SP - 2195
EP - 2197
JO - IEEE Transactions on Magnetics
JF - IEEE Transactions on Magnetics
SN - 0018-9464
IS - 6
M1 - 5467696
ER -