HighPerformance Polynorbornene Optical Waveguide forOpto-Electric Interconnections

waveguide. Inaddition, theO-Einterconnection with polymer waveguide also canprovide cost-effectiveness and We havenewlydeveloped a multi-mode polymermasrdcii .Anubroreach ousav optical waveguide withpolynorbornene (PNB). ThePNB c y. g waveguide.has e y lo o lls of0.03dreportedextensive results on polymeric materials for waveguideh haexteme lowo icaglsso 0.03dB/mo optical waveguide suchaspolyacrylates [1], [2], epoxies temperature (Tg)of270 - C.ThePNBwaveguide canbe [3], fluorinated polyimides [4], siloxanes [5], andsoon. tempratue (T) o 2700C.hePB wvegudecn b 0-B PCBsrequire long opztical circuit withmorethan1 formed byonly UV irradiation step without both1 etchilng O- PBreuelogptclicitwhmrehaI formed byvelopnly irradiatioy ustp wthot botho, tch meter andthetolerance ofareflow soldering process with anddeveloping processes. By usingthismethod, the waveguide canbeeasily patterned withvarious shapes such above 2500C. However, these polymers usually haveeither hiheroztical loss orlower heatresistance. Toovercome asY-branch, bend, taper, andsoon.Inaddition, we can ge fabricatethe minimumwaveguidepitchlessththese problems, wenewly developed PNBwaveguide that fabricate theminimum waveguie c an 75 f im haslowoptical loss, high heatresistance, lowmoisture with the50-pm-width core. W canaseilyfabriceabsorption, lowdielectric constant, andhigh flexibility. In stacked waveguide because te oreayerowitf srfceaddition, PNBwaveguide canbesimply formed byanUV canbeformed without aeh anda o roess.irradiation through aphoto-mask anda heating without InthePNB waveguide, 450mirror wasformedbyan bohecigaddvlpn prcse. excimer laser. Thismethodprovides asmall mirror (100 Forh 0-Bn P s dvertpical-catsu e - l ~im x200im)wth sooth urfae in espetive ForO-EPCBs, vertical-cavity surface-emitting laser x20ri) wih soothsuracen rspecivediode (VCSEL) andphoto diode (PD) aregenerally used. waveguides. Fromtheresult ofinsertion loss measurements, Troreitinecsayto bdigt toput g lih into totaloptical losswaslessthan2 d inan 8-cm-lengt Therefore, itiSnecessary tobendlight 90'toputlight into total optical losswasless than2dBinan8-cm-length aeud.Mn prahs uha 5 lp irra waveguide witht o45mirr. Frhroe e waveguide. Manyapproaches suchas45°slope mirror at wavoElegu rid withintwo r450nmirror FurthermBore new thewaveguide [6]-[7] andoptical pin[8]werereported. Opto-Electric (0-B) intposerco tioPN withguPNB opticalHowever, itisdifficult toemploy themforO-EPCBsdue waegidwspose. ThsPBwvgiehshg tocostproblem. Inthis paper, weproposed 450mirrors flexibility andhigh adaptability toreflow soldering processforebyean eximlaser. wereportdthat highdes becase fis hghg. herfor,te PB wvegidecan formedbyanexcimer laser. We report thathigh-density because~ ~~~~~~' ofishg.g,hrfre h N aeud a optical waveguide canbefabricated easily byusing this beformed inflexible printed circuit boards (PCBs) withoutsimpl proess. particular process, ascompared totheconventional PCB simple process fabrication process, whichleadsto lowcostO-E Experiments interconnection. A.Fabrication ofPNBWaveguide