Enhanced Spin Polarization by An Extra Co or CoFe Layer in FM/Insulator/FM Structures

High-temperature magnetoresistance study of a magnetic tunnel junction

“…The ratio of TMR can be generally understood by Julliere's model that polarization of magnetic layers plays a dominant role [5]. However, many essential factors, such as the interfacial effect, impurities, structures of the layers, and temperature, etc., change the properties of a TMR system [6]. Since the relatively high temperature due to post manufacturing processes after MTJ structure could cause considerable damage on the Magnetic tunneling junction (MTJ) structure and decrease the function of MRAM devices, the temperature dependence of TMR ratio is desired for practical application purpose [7][8][9].…”

Thermal stability study of the insulator layer in NiFe/CoFe/Al2O3/Co spin-dependent tunnel junction

“…Since the successful development of the large tunneling magnetoresistance (TMR) [1], there has been a great interest in the potential application of this structure due to the highly field-sensitive tunnel resistance. The TMR tunnel junctions with the structure of two ferromagnetic (FM) layers separated by a thin insulating layer (I) are known to change the tunnel resistance according to the relative magnetic orientations within the two FM layers [2]. However, the tunnel junction should be able to withstand thermal treatment up to 4001C for complementary metal oxide semiconductor compatibility, which is encountered in baked microelectronics integration processing with on-chip IC [3].…”