Pluggable optics are being pushed to their limits in terms of face plate density and power consumption requirements within emerging mega data centers and HPCs applications. Future applications seek silicon photonics based optical engines with ability for high channel count and throughput beyond 1Tb/s. In this paper, we show our results in development of single mode polymer-based optical-electrical PCBs (OEPCBs) supporting the emerging Si-Pho host PCB platforms with multi-terabit on-board routing capability for chip-to-chip communications. Single mode polymer waveguides (SM-PWGs) are fabricated using new photopatternable optical silicone materials (WG-2211/WG-2511-WG2711) on conventional PCBs. Test platform PCB shows designs with varying core sizes (20/15/12/9/7µm) and channel lengths (5-15cm). The measurements results show single-mode waveguides loss as less 0.4 dB/cm at 1310nm. Furthermore, the result show new waveguide material to be compliance for both rigid and flexible PCBs. OEPCB compliance evaluation test results shown in the paper includes results of lamination, chemical compliance, drilling, and plating tests. The results shown in the paper show first time ever fabrication of single mode polymer waveguide OEPCBs in production environment.
Siloxanes, which can be viewed as hybrids of glass and organic materials, have been used to fabricate polymer waveguides and devices that exploit the large thermo-optical effect of this material. Siloxanes have many unique properties including good thermal stability, chemical resistance, tunable refractive index, tunable mechanical properties and excellent photo-stability. The refractive index of siloxane polymer is composition dependent and generally ranges from 1.4 to 1.54. Introduction of porosity or composition modification can further expand refractive index range to 1.15~1.63. The loss and absorption characteristics for a variety of silicone-based polymers are examined and an example of a UV curable polymer coating illustrates the flexibility of the silicone polymer family to be tailored to meet specific application needs.
Silicone polymeric materials are being developed that will allow the hybrid integration of tunable functionality provided by polymer dispersed liquid crystal, PDLC, and continuous phase liquid crystal materials on planar silica-on-silicon and planar polymer light circuits. The advantages of this approach are ease of integration, the possibility for reduced power consumption, and therefore a reduction of the overall cost for component manufacturing and operation. A successful demonstration of a low loss approach to hybrid integration of polymers and liquid crystals is presented. The challenges for successful integration and acceptance will be discussed. New liquid crystal materials are being developed specifically for this application.
The AR layer prepared by chemical method is of renewed interest due to its higher laser damage threshold than that of AR film deposited by the vacuum evaporation method. The AR layer has been prepared on BK-7 glass substrate by neutral-solution processing in our laboratory and the results were reported in 1989. Recently, we improved the preparated condition that the transmittance increase from 99% at 1.06 micrometers and the laser damage threshold still remain about twice as the AR film prepared by vacuum evaporation method. The cross structure of the AR layer has been observed by TEM.