Journal of the Institute of Electronics Engineers of Korea SD (대한전자공학회논문지SD)

The Institute of Electronics and Information Engineers (대한전자공학회)
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Design of Traveling-Wave Type CPW Electrodes in a Mach-Zehnder Ti:$LiNbO_3$ Optical Modulator with a Grooved $SiO_2$ thin Film

Grooved $SiO_2$ 박막을 갖는 Mach-Zehnder Ti:$LiNbO_3$ 광변조기의 진행파형 CPW 전극설계

  • 한영탁 (서울市立大學院 電子工學科) ;
  • 김창민 (서울市立大學院 電子工學科) ;
  • 윤형도 (電子部品硏究員 素子通信部品硏究센터) ;
  • 임상규 (西江大學校 電子工學科) ;
  • 안철 (西江大學校 電子工學科) ;
  • 구경환 (電子部品硏究員 素子通信部品硏究센터)
  • Published : 2000.11.01
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Abstract

A Mach-Zehnder type $Ti:LiNbO_3$ optical modulator with a grooved $SiO_2$ buffer layer, was evaluated in terms of an electrode structure. The finite element method was performed to find out the optinum design parameters of electrodes. characteristic impedance ($Z_o$), MW effective index ($N_{eff}$) and attenuation constant ($a_o$)of fabricated traveling-wave electrodes were measured and compared with those obtained by the simulation expectation. For an optical modulator with 11${\mu}m$thick electrodes and a grooved $SiO_2$ buffer layer, the 3dB bandwidth based on the RF measurement results turned out to be 18GHz.

Goodved $SiO_2$ 박막을 갖는 Mach-Zehnder(M-Z)형태의 $Ti:LiNbO_3$ 진행파 광변조기의 전극구조를 변화시켜가며 유한요소법에 의한 해석을 수행하였다. 최적의 설계치를 추출하였으며, 제작된 전극에 대하여 특성임피던스($Z_o$), 마이크로파 유효굴절률($N_{eff}$), 감쇠정수($a_o$)를 측정하여 그 결과를 이론치와 비교하였다. 전극두께가 11${\mu}m$이고, $SiO_2$ 완중박막을 식각한 전극에 대하여, RF 측정결과로부터 계산된 3dB 변조대역폭은 18GHz로 나타났다.

Keywords

References

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