Fabrication of Bright Blue SrS:CuCl Thin-Film Electroluminescent(TFEL) Devices

고휘도 청색 발광 SrS:CuCl 박막 전계발광소자의 제작

  • 이순석 (檀國大學校 情報디스플레이 硏究所) ;
  • 임성규 (檀國大學校 電子工學科)
  • Published : 2000.01.01

Abstract

The sulfur pressure and TRA(rapid thermal annealing) conditions of the fabricated SrS:CuCl TFEL devices were optimized to improve blue color luminance. The thickness of the phosphor layer of SrS:CuCl TFEL devices fabricated by electron beam deposition system was 6000 ~ 8000 ${\AA}$. The fabricated TFEL devices were annealed at 800 $^{\circ}C$ for 3 min. It was shown that the crystallinity of SrS:CuCl phosphor was improved by an increase in RTA temperature and RTA time. Blue color was emitted from the TFEL device with emission peak wavelength of 468 nm and 500 nm. The CIE color coordinates were x = 0.21, y = 0.33. The luminance($L_{40}$) of TFEL device strongly depended on the sulfur pressure of deposition chamber and increased from 262 cd/$m^2$ to 728 cd/m2 as the sulfur pressure increased from $8{\times}10^{-6}$ torr to $2{\times}10^{-5}$ torr.

청색 발광 SrS:CuCl TFEL 소자의 휘도를 향상시키기 위하여 황 압력과 열처리 조건을 최적화하여 SrS:CuCl TFEL 소자를 제작하였다. 전자빔 증착 장비를 이용하여 SrS:CuCl 형광체를 6000 ~ 8000 ${\AA}$ 두께로 증착 시킨 후, 800 $^{\circ}C$에서 3분 동안 열처리하여 TFEL 소자를 제작시켰다. 형광체 결정은 열처리 온도 및 열처리 지속 시간의 증가에 따라 향상되었다. SrS:CuCl TFEL 소자는 468 nm 와 500 nm에서 발광 피크 파장을 나타내었고, CIE 색 좌표는 x = 0.21, y = 0.33로 청색 빛이 방출되었다. SrS:CuCl TFEL 소자의 휘도$(L_{40})$는 형광체 증착 중의 황 압력에 크게 의존하여 황 압력을 $8{\times}10^{-6}$ torr에서 $2{\tiems}10^{-5}$ torr로 증가시켰을 때 262 cd/$m^2$에서 728 cd/$m^2$로 증가되었다.

Keywords

References

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