Effects of the Introduction of UV Irradiation and Rapid Thermal Annealing Process to Sol-Gel Method Derived Ferroelectric Sr0.9Bi2.1Ta1.8Nb0.2O9 Thin Films on Crystallization and Dielectric/Electrical Properties

UV 노광과 RTA 공정의 도입이 Sol-Gel 법으로 제조한 강유전성 Sr0.9Bi2.1Ta1.8Nb0.2O9 박막의 결정성 및 유전/전기적 특성에 미치는 영향

  • 김영준 (고려대학교 재료공학과) ;
  • 강동균 (고려대학교 재료공학과) ;
  • 김병호 (고려대학교 재료공학과)
  • Published : 2004.01.01


The ferroelectric SBT thin films as a material of capacitors for non-volatile FRAMs have some problems that its remanent polarization value is relatively low and the crystallization temperature is quite high abovc 80$0^{\circ}C$. Therefore, in this paper, SBTN solution with S $r_{0.9}$B $i_{2.1}$T $a_{1.8}$N $b_{0.2}$$O_{9}$ composition was synthesized by sol-gel method. Sr(O $C_2$ $H_{5}$)$_2$, Bi(TMHD)$_3$, Ta(O $C_2$ $H_{5}$)$_{5}$and Nb(O $C_2$ $H_{5}$)$_{5}$ were used as precursors, which were dissolved in 2-methoxyethanol. SBTN thin films with 200 nm thickness were deposited on Pt/Ti $O_2$/ $SiO_2$/Si substrates by spin-coating. UV-irradiation in a power of 200 W for 10 min and rapid thermal annealing in a 5-Torr-oxygen ambient at 76$0^{\circ}C$ for 60 sec were used to promote crystallization. The films were well crystallized and fine-grained after annealing at $650^{\circ}C$ in oxygen ambient. The electrical characteristics of 2Pr=11.94 $\mu$C/$\textrm{cm}^2$, Ps+/Pr+=0.54 at the applied voltage of 5 V were obtained for a 200-nm-thick SBTN films. This results show that 2Pr values of the UV irradiated and rapid thermal annealed SBTN thin films at the applied voltage of 5 V were about 57% higher than those of no additional processed SBTN thin films. thin films.lms.s.s.


  1. Nature v.374 Fatigue-free ferroelectric capacitors with platinum electrodes C. A. Paz de Araujo;J.D.Cuchiaro;L.D.McMillan;M.C.Scott;J.F.Scott
  2. Appl. Phys. Lett. v.68 no.5 Metalorganic chemical vapor deposition of ferroelectric $SrBi_2Ta_2O_9$ thin films T.Li;Y.Zhu;S.B.Desu;C.H.peng;M.Negata
  3. Appl. Phys. Lett. v.66 no.2 Preparation & ferroelectric properties of $SrBi_2Ta_2O_9$ thin films K.Amanuma;T.Hase;Y.Miyasaka
  4. Integrated Ferroelectrics v.15 A critical comparative review of PZT and SBT-based science and technology for non-volatile ferroelectric memories O.Auciello
  5. Integrated Ferroelectrics v.26 Review of $SrBi_2Ta_2O_9$ thin films capacitor processing C.Dehm;W.Harner;G.Schindler;R.Bergmann;B.Hasler;I.Kasko;M.Kastner;M.Schiele;V.Weinrich;C.Mazure
  6. FRAM IC card Technology K.H.Kim;B.G.Yo;H.C.Lee
  7. J. of KIEEME v.13 no.8 Effects of bottom electrode to dielectric and electrical propertics of MOD derived ferroelectric SBT thin films T.H.Kim;S.P.Song;B.H.Kim
  8. J. KIEEME v.13 no.4 Study on low temperature formation of ferroclectric $Sr_{0.9}Bi_{2.1}Ta_2O_9$ thin films by Sol-Gel process and rapid thermal annealing H.H.Jang;S.P.Song;B.H.Kim
  9. Technical Digest of the IEDM v.94 A Half Micron ferroelectric memory cell technology with stacked capacitor structure S.Ohnishi;K.Ishihara;Y.Ito;S.Yokoyama;J.Kudo;K.Sakiyama
  10. Ferroelectrics v.82 K.Singh;D.K.Bopardikar;D.V.Atkare
  11. Belletin of KIEEME v.13 no.4 FRAM 응용을 위한 강유전체 박막의 형성 기술 W.S.Lee;S.Y.Kim
  12. J. of Mater. Sci. v.10 Direct Fine-Patterning of PZT thin films using photosensitive gel films derived from chemically modified metal alkoxides N.Tohge;Y.Takama
  13. J. Kor. Ceram. Soc. v.39 no.8 A study on fabrication of photosensitive $Sr_{0.9}Bi_{2.1}Ta_2O_9$ thin film by Sol-Gel self-patterning technique K.H.Yang;T.H.Park;T.Y.Lim;
  14. Jpn. J. Appl. Phy. v.40 Preparation and properties of $SrBi_2Ta_2O_9$ ferroelectric thin films using excimer UV irradiation and seed layer T.Hayashi;D.Togawa
  15. J. Mater. Lett. v.52 Novel chemical processing for crystallization of $SrBi_2Ta_2O_9$ thin via UV irradiation K.Nichizawa;T.Miki;K.Suzuki;K.Kato
  16. Integrated Ferroelectrics v.17 Development of a new annealing process to allow new top electrode materials for $SrBi_2Ta_2O_9$ capacitors K.Wadanabe;M.Tanaka;N.Nagel;K.Katori;M.Sugiyama;H.Yamoto;H.Yagi
  17. Proceeding of Workshop on Ferroelectrics and FRAM Technology Low temperature formation of ferroelectric $Sr_{0.9}Bi_{2.1}Ta_2O_9$ and $Sr_{0.9}Bi_{2.1}(Ta_{0.9}Nb_{0.1})_2O_9$ thin films by Sol-Gel process S.P.Song;B.K.Sun;B.H.Kim
  18. Integrated Ferroelectrics v.14 New low temperature processing of Sol-Gel $SrBi_2Ta_2O_9$ thin films Y.Ito;M.Ushikubo;S.Yokoyama;H.Matsunaga;T.Atsuki;T.Yonezawa;K.Ogi
  19. J. Electric and Electronic Materials v.13 no.4 Study on low temperature formation of ferroelectric $Sr_{0.9}Bi_{2.1}Ta_2O_9$ thin films by sol-gel process and rapid thermal annealing H.H.Jang;S.P.Song;B.H.Kim
  20. J. Electric and Electronic Materials v.12 no.1 Dielectric properties of ferroelectric $Sr_{0.7}Bi_{2.3}(Ta_1 _xNb_x)_2O_9$ thin films prepared by MOD process M.Y.Choi;S.P.Song;B.J.Jeon;B.H.Kim
  21. Appl. Phys. Lett. v.68 no.5 Metaloganic chemical vapor deposition of ferrelectric $SrBi_2Ta_2O_9$ thin films T.Li;Y.Zhu;S.B.Desu
  22. Ph. D. Thesis, Korean University A study on fabrication of photosensitive $Sr_{0.9}Bi_{2.1}Ta_2O_9$ thin film by Sol-Gel Self-patterning technique (in Kor.) T.H.Park
  23. Jpn. J. Appl. Phys. v.37 Effects of morphological changes of Pt/$SrBi_2Ta_2O_9$ interface on the electrical properties of ferroelectric capacitor D.S.Sin;H.N.Lee