Research Of Electro-optical Modulation Characteristics Of Integrated Optical Waveguide Micro-ring Resonator

With the rapid development of integrated optics, modern SoC (System on Chip)technology based on SOI devices has become the main stream of future opticalcommunication and integration. Because of the unique advantage of SoC devices on opticalprocess, optical calculation, optical transmission and optical control, it has become theresearch hot topic in recent academic world both home and abroad. However, the mainbottleneck restricting the development of SoC is the integration problem. And sincehigh-quality SOI materials have high difference of refractive index, transparent transmissionof communication channel and fully compatibility with CMOS fabrication process, it canreduce the chip sizes and increase chip integration density in great degree to realize theconnection and integration for photo electronics. So SOI material becomes the first choice forthe fabrication of discrete devices in SoC integration. SOI micro-ring resonator, as the mainpart of integrated optics, can be applied to filtering, optical switch, modulator, detector, etc.As further explanation of silicon photoelectric effect due to semiconductor physics theory andquantum mechanics, the research on SOI micro-ring resonant electro optical modulatorbecomes the focus and difficult issue recently. SOI micro-ring modulator based on siliconphotoelectric effect realizes the modulation and shiftiness of optical signal by the change ofwaveguide refractive index. It becomes the best solution in making high-speed opticalmodulator and optical switch because it overcomes the limitation of thermal diffusion andradiation when thermo-optic effect modulator is heated, break through the problem of lowrespond speed compared with acuosto-optic devices and have high modulation speed.Therefore, research on electro-optical modulators based on SOI micro-ring waveguide is thebasis of the realization of modern SoC devices.In this paper, we aimed at electro-optical modulators based on SOI micro-ringwaveguide, simulated and analyzed the single-mode property, highlight locality and resonantresponse of waveguide by FDTD and Rsoft. Based on these results, striped and ridged nano-waveguide resonator is designed and fabricated, then this structure is optimized and thebending loss of resonator with the radius of15μ mis tested, the optimized loss valueis0.0109±0.0001d B/turn, Q factor can still remain above104. In this way, the demand ofbasic parameters of the research on resonant response and the fabrication of resonators can beachieved. Afterwards, the characteristics of diode and the realization of P-N junction by ionimplantation is simulated, analyzed and calculated by Sentaurus and SRIM2008, and finallywe defined the detailed data parameters. Finally we use standard MEMS process like ICPetching, electron-beam lithography and ion implantation to fabricate electro-optical modulatorchip based on SOI micro-ring resonator. The result of static and transient modulatingcharacteristic of micro-ring electro-optical modulator with the scope of free wave2.6nm whenan outside drive voltage signal is applied is: static test produces resonant frequency shift andthe resonant frequency is increased with the increase of drive voltage signal, when the drivevoltage crest value reached certain degree, P-N junction is broken down.By conductingtransient characteristic test, it is obtained that the modulation depth is0.899,the extinctionratio is10.14dB and the maximum modulation frequency is30MHz.