Achievement

The improvement of Magnetic Tunnel Junctions (MTJ) will lead to greater MRAM capacity and sensing applications. Seeking to identify a better MTJ composition, we fabricated GaN-based metal ferroelectric semiconductor structure using Barium Titanate (BTO) as dielectric layer grown by pulsed laser deposition. The voltage (C-V) measurements show the hysteresis at high frequency 2MHz and it tracks the trend of high-K dielectric behavior on n-type GaN semiconductor. The C-V characteristics of BTO/GaN structures depict the metal oxide semiconductor behavior with clear transition from accumulation, depletion at a flat band voltage of 3.28 V. In addition, BTO layer has been grown on magnetic LaSrMnO film and polarization studies show that the BTO layer can be locally polarized - very first study in this field. The demonstration of local polarization of the ultra-thin piezoelectric film surface enhances our understanding of the functionality of MTJs where this is used as an insulating layer.