Title :
Integration of SBT thin film into MFMOS structure for one transistor memory applications
Author :
Zhang, Fengyan ; Hsu, Sheng Teng ; Ying, Hong ; Evans, Dave ; Ohnishi, Shigeo ; Zhen, Wendong
Author_Institution :
Sharp Labs. of America, Inc, Camas, WA, USA
Abstract :
The SBT thin film has been successfully integrated into a MFMOS structure for one-transistor memory applications. A new high temperature stable electrode, IrMO, that consists of Ir, metal, and O was used as the bottom electrode. This new electrode can maintain good conductivity and integrity even after very high temperature (800-1000°C) oxygen ambient annealing. Therefore the SBT film can be deposited on the bottom electrode using MOD methods and annealed at high temperature (700-800°C) without any hillock and peeling problems. Excellent ferroelectric properties were achieved. The thermal stability of the bottom electrode on thin gate oxide (35 Å) was also very stable. Good C-V characteristics maintained even after the SBT capacitor formation. The etching damage to the SBT capacitor stack can be minimized by optimizing the etching conditions. No polarization loss and just slightly Ec increase was observed after etching of the SBT capacitor stack. The aluminum oxide based passivation layer was successfully integrated into this device with excellent passivation properties. Finally, the memory window of the MFMOS device will be presented
Keywords :
MIS structures; annealing; bismuth compounds; capacitance; etching; ferroelectric capacitors; ferroelectric storage; ferroelectric thin films; passivation; strontium compounds; thermal stability; 700 to 800 C; 800 to 1000 C; C-V characteristics; Ir-O; MFMOS structure; MOD methods; SBT capacitor stack; SrBi2Ta2O9; SrBi2Ta2O9 thin film integration; aluminum oxide based passivation layer; bottom electrode thermal stability; conductivity; etching damage; ferroelectric properties; high temperature oxygen ambient annealing; high temperature stable electrode; memory window; one transistor memory applications; Annealing; Capacitors; Conductivity; Electrodes; Etching; Ferroelectric films; Ferroelectric materials; Passivation; Temperature; Transistors;
Conference_Titel :
Applications of Ferroelectrics, 2000. ISAF 2000. Proceedings of the 2000 12th IEEE International Symposium on
Conference_Location :
Honolulu, HI
Print_ISBN :
0-7803-5940-2
DOI :
10.1109/ISAF.2000.942404