DOI QR코드

DOI QR Code

Optoelectronic properties of the Metal-dielectric complex thin films for applying high sensitivity IR image sensors

고감도 적외선 이미지 센서 적용을 위한 금속-유전체 복합 박막의 광전자 특성

  • Kim, Ye-Na (School of Advanced Materials Science and Engineering, Sungkyunkwan University) ;
  • Kwon, Soon-Woo (School of Advanced Materials Science and Engineering, Sungkyunkwan University) ;
  • Park, Seung-Jun (Department of Materials Science and Engineering, Hanyang University) ;
  • Kim, Woo-Kyug (Korea Electronics Technology Institute) ;
  • Lee, Han-Young (Korea Electronics Technology Institute) ;
  • Yoon, Dae-Ho (School of Advanced Materials Science and Engineering, Sungkyunkwan University) ;
  • Yang, Woo-Seok (Korea Electronics Technology Institute)
  • Received : 2010.11.08
  • Accepted : 2010.12.24
  • Published : 2011.04.30

Abstract

High sensitivity IR image sensors require materials characteristics with temperature coefficient of resistance (TCR) and IR range absorption. In this study, the metal-dielectric thermo sensitive films (MDTF) based on $(SiO_2)_x-(Ti)_y$ composition were deposited on substrates of germanium and glass by thermal evaporator. The $SiO_2$ : Ti mixture was made from the ratio of 9 : 1, 8 : 2, 7 : 3, 6 : 4, respectively. $(SiO_2)_x-(Ti)_y$ mixture powder was loaded on tungsten boat in evaporator and was 15.5 cm from the substrate. Resistance of $(SiO_2)_x-(Ti)_y$ in the range of 273~333K were measured as a function of temperature. Temperature coefficient of resistance (TCR) was calculated by the resistance variation. Under the various mixture ratios condition, it is possible to obtain $SiO_2$-Ti layers with resistance from units kilo-ohm to hundreds kilo-ohm. Finally, our results showed that Temperature coefficient of resistance (TCR) of these films varies from -1.4 to $-2.6%K^{-1}$.

고감도 적외선 이미지 센서에 적용이 가능한 우수한 TCR(temperature coefficient of resistance) 값을 갖고 적외선 파장영역에서 흡수 특성을 갖는 막 형성을 위해, 본 연구에서는 Silica와 Titanium 분말을 혼합비율을 달리하여 준비한 후 열 기상 증착기를 이용하여 상온에서 게르마늄과 유리 기판 위에 각각 $(SiO_2)_x-(Ti)_y$ 막을 제작하였다. 챔버 내에 위치한 혼합분말이 담겨진 텅스텐 보트와 기판 간의 거리는 15.5 cm이며, 사용된 $SiO_2$와 Ti 분말의 혼합비율 x : y는 각각 90 : 10,80 : 20, 70 : 30, 60 : 40이다. $(SiO_2)_x-(Ti)_y$ 막의 전기적 저항은 273~333 K 영역에서 온도 변화에 따라 측정하였으며, TCR 값은 측정된 막의 저항 값으로부터 계산되었다. 다양한 혼합비율 조건 하에서 형성된 $(SiO_2)_x-(Ti)_y$ 막은 수 $k{\Omega}$~수백 의 $k{\Omega}$ 저항특성을 보였으며, 이러한 막의 TCR은 $-1.4{\sim}-2.6%K^{-1}$의 다양한 값을 나타내었다.

Keywords

References

  1. J.M. Lloyd, "Themal Imaging Systems", Plenum Press, New York (1975).
  2. J.L. Miller, "Principles of Infrared Technology", Van Nostrum Reinhold, New York (1994).
  3. R.S. Balcerak, "Uncooled IR imaging: technology for the next generation", Infrared Technol. Appl. XXV, SPIE 3698 (1999) 110.
  4. P.G. Datskos, N.V. Lavrik and S. Rajic, "Performance of uncooled microcantilever thermal detectors", Rev. Sci. Instrum 75 (2004) 1134. https://doi.org/10.1063/1.1667257
  5. S.R. Hunter, G. Maurer, L. Jiang and G. Simelgor, "Highsensitivity uncooled microcantilever infrared imaging arrays", Proc. SPIE, 6206 (2006) 620 61J-1-620 61J-11.
  6. D. Grbovic et al., "Uncooled infrared imaging using bimaterial microcantilever arrays", Appl Phys. Lett. 89 (2006) 073118. https://doi.org/10.1063/1.2337083
  7. V. Yu. Zerov et al., "Features of the operation of a bolometer based on a vanadium dioxide film in a temperature interval that includes a phase transition", J. Opt. Technol. 66 (1999) 387. https://doi.org/10.1364/JOT.66.000387
  8. C. Chen, X. Yi, J. Zhang and X. Zhao, "Linear uncooled microbolometer array based on $VO_x$ thin films", Infrared Phys. Technol. 42 (2001) 87. https://doi.org/10.1016/S1350-4495(01)00058-5
  9. K.C. Liddiard, "Thin-film resistance bolometer IR detectors - II", Infrared Physics 26 (1986) 43. https://doi.org/10.1016/0020-0891(86)90046-1
  10. K.C. Liddiard, M.H. Unewisse and O. Reinhold, "Design and fabrication of thin film monolithic uncooled infrared detector arrays", SPIE, 2225 (1994) 62.
  11. E.V. Michailovskaya, I.Z. Indutnyy and P.E. Shepeliavyi, "Inhomogeneous SiOx metal-dielectric films as a material for infrared thermal radiation detectors", Technical Physics 48(2) (2003) 261. https://doi.org/10.1134/1.1553571
  12. K. Haga and H. Watanabe, "A structural interpretation of Si---O---Si vibrational absorption of high-photoconductive amorphous a-SiO_x$ : H films", 195(1-2) (1996) 72. https://doi.org/10.1016/0022-3093(95)00544-7
  13. J.D. Vinent, "Fundamentals of infrared detector operation and testing", Wiley (1990).
  14. J.E. Morris, "Structure and electrical properties of Au- SiO thin film cermets", Thin Solid Films 11 (1972) 299. https://doi.org/10.1016/0040-6090(72)90056-9