Silicon Optical Modulators at 1.3 μm Based on Free-Carrier Absorption

Silicon optical waveguide modulators, appropriate for operation in the 1.3-1.55-μm wavelength region, have been fabricated and their performance characterized at the wavelength of 1.3 μm. The modulator structures consist of p-i-n diodes integrated with silicon waveguides; device operation is based on free-carrier absorption. Modulation depths of -6.2 dB and response times (τ) less than 50 ns have been measured. Experimental results are compared with the p-i-n diode theory. © 1991 IEEE