Title :
Substrate Biasing Effect during MgO Deposition in CoFeB/MgO/CoFeB MTJs
Author :
Choi, G.M. ; Shin, K.H. ; Seo, S.A. ; Kim, S.O. ; Lim, W.C. ; Lee, T.D.
Author_Institution :
Center for Spintronics Res., KIST, Seoul
fDate :
6/1/2009 12:00:00 AM
Abstract :
High tunneling magnetoresistance (TMR) ratio and low RA in magnetic tunnel junctions are necessary condition for application in magnetic random access memory. To get high TMR ratio and low RA, good quality of MgO (002) insulating layer is important. To increase crystalline quality of MgO (002) layer, we applied negative bias on the substrate during MgO deposition. We report the results of the tunneling magnetoresistance (TMR) ratio and the resistance-area product (RA) for CoFeB/MgO/CoFeB magnetic tunnel junctions (MTJs) with substrate bias voltage, and showed TMR increase and RA decrease with substrate bias. The effects of substrate bias voltage on the TMR ratio, RA and MgO (002) peak intensity are discussed.
Keywords :
MRAM devices; boron alloys; cobalt alloys; ferromagnetic materials; insulating thin films; iron alloys; magnesium compounds; tunnelling magnetoresistance; CoFeB-MgO-CoFeB; MgO (002) insulating layer; high tunneling magnetoresistance; magnetic random access memory; magnetic tunnel junctions; substrate biasing effect; Magnetic tunnel junctions (MTJs); resistance-area product (RA); substrate bias; tunneling magnetoresistance (TMR);
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2009.2018577