Boron effects on noise in magnetic tunnel junctions

Normalized noise at different boron atomic percentages varying from 20%, 25%, and 30% was shown to increase with increasing boron content. The TMR% of the junction with 30% boron content shows almost 0% TMR. The X-ray diffraction patterns on these junctions, suggesting that the degree of crystallinity in MgO with increasing boron content, have deteriorated. Thus, high crystallinity is not only a vital factor for obtaining a high TMR ratio but also serve as a facilitating condition for lower noise.