Low Voltage, High Speed High Contrast Electrooptical Thin Film Devices for FreeSpace Optical Interconnects

摘要

Speed and 'crosstalk' limitations, encountered by conventional metal transmissionlines in 'chip to chip' data/information communication are overcome by Free Space Optical Interconnects (FSOI) for future ultra fast computing/communications systems. Fabry-Perot thin film Electrooptic(EO) modulators (STFP) function as high speed, low voltage operable optical interconnects. Development and demonstration of such STFP's based on ferroelectric/EO F-P modulators is described. For self tuning, with respect to F-P cavity Ferroelectric(FE)/EO thin film thickness variations and consequent nonuniformity of extinction/contrast across STFP arrays, a holographic mirror (photorefractive LiNbO3) for compensation of thickness was used. For proof-of-concept demonstration, a PLZT bulk crystal plate was used for STFP arrays. A successful demo of 8x8 and 16x16 STFP interconnect arrays is described. The development of KTN (FE/EO) thin films on Sapphire substrates by RF-planar magnetron sputtering (for IC compatibility) and PLZT, low level of effort, backup material are described. Successful FE properties observation in KTN and PLZT, materials characterization (structural and stoichiometric) and property evaluation are presented. The challenges presented in STFP applications are described. Deficiencies of K, primarily due to negative ion re-sputtering effects in KTN, Pb volatilization in PLZT and extraneous Pyrochlor phases are described.