Title :
Low-temperature preparation and characterization of SrxBi2+yTa2O9/SiO2 /Si structure for MFOS memory FET
Author :
Matsumuro, Yoshinori ; Sugiyama, Hideki ; Noda, Minoru ; Okuyama, Masanori
Author_Institution :
Osaka Univ., Japan
Abstract :
Preferentially (105)-oriented Sr0.7Bi2.8Ta 2O9 thin films on SiO2/n-Si(100) have been prepared by laser ablation at low temperature as low as 350°C, which is the lowest process temperature for growing a SBTO ferroelectric thin film. Dielectric properties of the SBTO film have been improved by increasing Sr/Bi atomic ratio from 0.7/2.8 to 0.7/2.0. A memory window of as large as 3.6 V in the MFOS capacitor has been obtained at the Sr/Bi of 0.7/2.0 and is the largest value in the MF(I)S diode structures. Also little C-V degradation is observed for Sr/Bi of 0.7/2.0 up to fatigue cycle over 1010, keeping memory window of more than 3.2 V. It should be emphasized that improvement in memory characteristics is strongly related to insulating properties of the ferroelectric and dielectric thin films rather than its value of dielectric constant
Keywords :
bismuth compounds; dielectric hysteresis; dielectric polarisation; ferroelectric materials; ferroelectric storage; ferroelectric thin films; permittivity; pulsed laser deposition; strontium compounds; (105)-oriented Sr0.7Bi2.8Ta2O 9 thin films; 3.6 V; 350 C; C-V degradation; MFOS memory FET; Sr0.7Bi2.8Ta2O9; SrxBi2+yTa2O9/SiO 2/Si structure; characterization; dielectric constant; dielectric properties; ferroelectric thin film; laser ablation; low-temperature preparation; memory window; Atomic beams; Bismuth; Capacitors; Dielectric films; Dielectric thin films; Ferroelectric films; Ferroelectric materials; Laser ablation; Strontium; Temperature;
Conference_Titel :
Applications of Ferroelectrics, 1998. ISAF 98. Proceedings of the Eleventh IEEE International Symposium on
Conference_Location :
Montreux
Print_ISBN :
0-7803-4959-8
DOI :
10.1109/ISAF.1998.786636
