Title :
High quality magnetic tunnel junctions for MRAM using reactively sputtered Al2O3 barriers
Author :
Tsunoda, Takaaki ; Mauri, Daniele
Author_Institution :
ANELVA Corp., San Jose, CA, USA
Abstract :
Reactive AlOx barrier layers are deposited by pulsed DC magnetron sputtering for magnetic tunnel junctions of MRAMs. The films are annealed at 285°C for 5 hours in a 13 KOe field. The deposition time is constant at 58 sec, while the O2 flow is varied from 5.4 to 7.4 sccm and the Ar flow is kept constant. Low O2 flows produce high junction resistance and low tunnelling magnetoresistance (TMR). It is clear that low O2 flows lead to higher resistance area (RA) because of thicker deposited barrier. This is due to the longer times in the metallic state. The poor TMR at these low O2 flows is due to O2 deficiency.
Keywords :
aluminium compounds; magnetic storage; random-access storage; sputter deposition; tunnelling magnetoresistance; 285 degC; 5 hour; 58 s; Al2O3; MRAM; annealing; magnetic tunnel junction; pulsed DC magnetron sputtering; reactive barrier layer; tunnelling magnetoresistance; Artificial intelligence; Magnetic materials; Magnetic tunneling; Oxidation; Oxygen; Plasma devices; Plasma materials processing; Radio frequency; Sputtering; Voltage;
Conference_Titel :
Magnetics Conference, 2005. INTERMAG Asia 2005. Digests of the IEEE International
Print_ISBN :
0-7803-9009-1
DOI :
10.1109/INTMAG.2005.1463854
