Design of monolithically integrated GeSi electro-absorption modulators and photodetectors on a SOI platform.

We present a design of monolithically integrated GeSi electroabsorption modulators and photodetectors for electronic-photonic integrated circuits on a silicon-on-insulator (SOI) platform. The GeSi electroabsorption modulator is based on the Franz-Keldysh effect, and the GeSi composition is chosen for optimal performance around 1550 nm. The designed modulator device is butt-coupled to Si(core)/SiO(2)(cladding) high index contrast waveguides, and has a predicted 3 dB bandwidth of >50 GHz and an extinction ratio of 10 dB. The same device structure can also be used for a waveguide-coupled photodetector with a predicted responsivity of > 1 A/W and a 3 dB bandwidth of > 35 GHz. Use of the same GeSi composition and device structure allows efficient monolithic process integration of the modulators and the photodetectors on an SOI platform.

[1]  M. Lipson,et al.  Nanotaper for compact mode conversion. , 2003, Optics letters.

[2]  David E. Aspnes,et al.  Electro-Absorption Effects at the Band Edges of Silicon and Germanium , 1966 .

[3]  Yasuhiko Ishikawa,et al.  Deformation potential constants of biaxially tensile stressed Ge epitaxial films on Si ( 100 ) , 2004 .

[4]  Fred H. Pollak,et al.  Piezo-Electroreflectance in Ge, GaAs, and Si , 1968 .

[5]  B. Jagannathan,et al.  40 Gbit/sec circuits built from a 120 GHz f/sub T/ SiGe technology , 2001, GaAs IC Symposium. IEEE Gallium Arsenide Integrated Circuit Symposium. 23rd Annual Technical Digest 2001 (Cat. No.01CH37191).

[6]  D. Miller,et al.  Strong quantum-confined Stark effect in germanium quantum-well structures on silicon , 2005, Nature.

[7]  Yasuhiko Ishikawa,et al.  Strain-induced band gap shrinkage in Ge grown on Si substrate , 2003 .

[8]  D. Ahn,et al.  Electronic-photonic integrated circuits on the CMOS platform , 2006, SPIE OPTO.

[9]  B. Santo,et al.  Solid State , 2012 .

[10]  Richard A. Soref,et al.  Silicon-based optoelectronics , 1993, Proc. IEEE.

[11]  Shen,et al.  Generalized Franz-Keldysh theory of electromodulation. , 1990, Physical review. B, Condensed matter.

[12]  J. Michel,et al.  Large Electro-Optic Effect in Tensile Strained Ge-on-Si Films , 2006, 3rd IEEE International Conference on Group IV Photonics, 2006..

[13]  Ludovic Desplanque,et al.  Detection of picosecond electrical pulses using the intrinsic Franz–Keldysh effect , 2001 .

[14]  Qianfan Xu,et al.  Micrometre-scale silicon electro-optic modulator , 2005, Nature.

[15]  M. Paniccia,et al.  A high-speed silicon optical modulator based on a metal–oxide–semiconductor capacitor , 2004, Nature.

[16]  P. Lawaetz,et al.  Valence-Band Parameters in Cubic Semiconductors , 1971 .