The field emission characteristics of an oxidized porous polysilicon field emitter using Pt/Ti emitter-electrode

Pt/Ti 전극을 사용한 산하된 다공질 폴리 실리콘 전계방출소자의 특성

  • Han Sang-Kug (School of Electrical Engineering and Computer Science Kyungpook National University) ;
  • Park Keun-Yong (School of Electrical Engineering and Computer Science Kyungpook National University) ;
  • Choi Sie-Young (School of Electrical Engineering and Computer Science Kyungpook National University)
  • Published : 2005.06.01

Abstract

In this paper, OPPS(oxidized porous poly-silicon) field emitters were fabricated by using various emitter-electrode metal and these electron emission characteristics were investigated for different thermal annealing effects. The addressed OPPS field emitter with Pt/Ti emitter electrode annealed at $300^{\circ}C$-1hr showed the efficiency of $2.98\%$ at $V_{ps}$=12 V and one annealed at $350^{\circ}C$-1hr showed the highest efficiency of $3.37\%$at $V_{ps}$=16V. They are resulted from the improvement of interfacial contact characteristics of thin emitter metal to an oxidized porous poly-silicon and the decrease of electrical resistance of emitter metal. The brightness of the OPPS field emitter increases linearly in $V_{ps}$ and after oxidation process for $900^{\circ}C$-50min, the brightness of the OPPS field emitter with the as-deposited Pt/Ti emitter electrode was 3600 cd/$m^2$ at the $V_{ps}$=15 V, 6260 cd/$m^2$ at the $V_{ps}$=20 V. Thermal treatment improved the adhesion between the Ti buffer layer and the oxidized porous poly-silicon and also played an important role in the uniform distribution of electric field to the emitter electrode.

본 논문에서는 다양한 에미터 금속 재료를 이용하여 산화된 다공질 폴리실리콘(Oxidized Porous Poly-Silicon) 전계방출 소자를 제조하였으며 에미터 금속의 열처리 효과가 산화된 다공질 폴리실리콘 전계방출소자의 특성에 미치는 영향을 조사하였다. 다양한 에미터 금속 중 구동전극을 가진 Pt/Ti 에미터 전극을 $300^{\circ}C$-1hr 열처리한 경우 전자방출 효율은 $V_{ps}$=12 V에서 최대 $2.98\%$의 효율을 나타내었으며, $350^{\circ}C$-1hr 열처리한 경우 $V_{ps}$=16V에서 $3.37\%$의 가장 높은 효율을 나타내었다. 이는 열처리 공정을 통해 OPPS 전계방출 소자 표면에 다수의 결정립 경계와 무수히 많은 미세한 다공질 간의 흡착성의 개선으로 인한 면 저항 감소에 의한 것을 알 수 있다. OPPS 전계 방출 소자를 디스플레이소자로 적용하기 위해 형광체 발광 특성을 조사해 본 결과, $900^{\circ}C$-50min 산화 후 Pt/Ti(5nm/2nm) 에미터 전극을 사용하여 제조된 OPPS 전계 방출 소자의 경우 15 V에서 3600 cd/$m^2$, 20 V에서 6260 cd/$m^2$의 상대적으로 높은 휘도를 나타내었다. 열처리는 Ti층과 OPPS 간의 흡착성을 개선시키고 에미터 전극에 고른 전계를 가하는 중요한 역할을 한다.

Keywords

References

  1. C. A. Spindt, I. Brodie, L. Humphrey, and E. R. Westerberg, 'Physical properties of thin-film field emission cathodes with molybdenum cones,' J. Appl. Phys, Vol. 47, pp. 5248-5263, 1976 https://doi.org/10.1063/1.322600
  2. Kusunoki. T., and Suzuki. M., 'Increasing emission current from MIM cathodes by using an Ir-Pt-Au multilayer top electrode,' Electron Devices, IEEE Transactions on,. 47 , pp. 1667-1672, 2000 https://doi.org/10.1109/16.853046
  3. S. Uemura, T. Nagasato, J. Yotani, T. H. Kurachi, and H. Yamada, 'Large Size FED with Carbon Nanotube Emitter,'SID'02 Digest, p. 1132, Sanjose, USA, 2002 https://doi.org/10.1889/1.1830144
  4. N. Negishi, T. Chuman, S. Iwasaki, T. Yoshikawa, H. Ito, and K. gasawara, 'High Efficiency Electron-Emission in Pt/SiOx/Si/Al Structure,' J. Appl. Phys., Vol. 36, p. 939, 1997 https://doi.org/10.1143/JJAP.36.L939
  5. M. Okuda, S. Matsutani, A. Asai, A. Yamano, K. Hatanaka, T. Hara, and T. Nakagiri, 'Electron Trajectory Analysis of Surface Conduction Electron Emitter Displays (SEDs),' SID Symposium Digest 29, p. 185, California, USA, 1998 https://doi.org/10.1889/1.1833724
  6. Y. Nakajima, A. Kojima and N. Koshida, 'A solid-state light-emitting device based on excitation of ballistic electrons generated in nanocrystalline porous poly-silicon films,' Jpn J. Appl. Phys, Vol. 41, pp. 2707-2709, 2002 https://doi.org/10.1143/JJAP.41.2707
  7. T. Komoda, Y. Honda, T. Hatai, Y. Watabe, T. Ichiha ra, K Aizawa, Y. Kondo, and N. Koshida, 'Fabrication of Ballistic Electron Surface-Emitting Display on Glass Substrate,' SID'01, Technical Digest, p. 428, 2000
  8. Seong-Chan Bae, Sang-Kug Han, and Sie-Young Choi,'Oxide-thickness effects on the field-emission characteristics of an oxidized porous poly-silicon field emitter,' Journal of the Korean Physical Society, Vol. 43, pp. 1053-1055, December 2003
  9. S. K. Han, S. I. Kwon, S. C. Bae, and S. Y. Choi, 'Effects of the thermal annealing on the field emission characteristics of an oxidized porous poly-silicon field emitter,' IDW'04, pp. 1233-1236, Niigata, Japan, 2004