"glassPack": A novel photonic packaging and integration technology using thin glass foils

"glassPack" will be introduced as a novel photonic packaging concept for a wide area of applications like high-speed electronic systems and sensors. The usage of thin glass foils with a thickness of some tens of microns as substrate and interconnection material will be discussed. Photonic packaging in such hybrid optoelectronic systems involves single packages, modules, and subsystems comprising at least one optoelectronic device, micro-optical element or optical interconnection. Thin glass is a commercially available and reliable material with high thermal resistance and excellent optical properties. Because glass is a well known material, many technologies like polishing, plating, etching and refractive index tuning are already known. In combination with newly developed integration technologies, a complete glass based package on wafer level can be realized. The main ideas of the "glassPack" concept are: selection of suitable glass foils as substrate material, realizat ion of microsystem compatible structuring technologies like cutting, drilling and etching, integration of optical waveguides by ion-exchange for single- and multi-mode applications, implementation of optical interconnects between fibres and integrated waveguides by laser fusion, integration of electrical wires and feed throughs, assembly of electronic and optoelectronic components, and bonding of the thin glass foils to 3D-stacks. Furthermore, the integration of micro fluidic channels into a "glassPack" will be supported. A sensor module containing optical waveguides, fluidic channels, electrical wires and components like a laser, two photodiodes and two flip-chips will be presented to demonstrate the suitability of glass as a material for integrated microsystems

Low-loss telecom wavelength board-level optical interconnects in thin glass panels by ion-exchange waveguide technology

An optical interconnection technology for 1310 and 1550 nm has been developed by using commercial available thin glass panels for waveguide fabrication. Process and mode-field distribution can be designed according optical requirements and simulated by combined FEM algorithms

Development of an electro-optical circuit board technology with embedded single-mode glass waveguide layer

The goal of our research is the development of a single-mode electro-optical circuit board, the single-mode board-to-board pluggable connector and the single-mode chip-to-board coupling interface to silicon photonic devices. In this paper, the single-mode glass waveguide process is presented based on thermal silver ion-exchange for fabrication of low loss glass waveguide panels that will be developed for embedding as core layer of such printed circuit board. The single-mode glass waveguides (SM-WGs) were fabricated on 150 mm wafer size for characterization of different embedding scenarios. In the best case the measured propagation loss before and after lamination is below 0.1 dB/cm (λ=1550 nm). A suitable glass waveguide layer and embedding process was developed that can be applied for single-mode electro-optical circuit board fabrication

Glass carrier based packaging approach demonstrated on a parallel optoelectronic transceiver module for PCB assembling

Glass as a carrier material for electrical and optical interconnects has many benefits compared to conventional materials like silicon, ceramic or polymer based laminates because of its excellent dielectric and transparent properties that are becoming important for electrical high-frequency signal wiring as well as for optical wave guiding. Furthermore, the integration potential of glass is excellent because of the dimensional stability under thermal load and the coefficient of thermal expansion matching that of silicon ICs. A small pitch size of conductor traces, small scale through-vias and high alignment accuracy are the key requirements that will be achieved from glass carrier based packaging. Another outstanding benefit is the transparency of glass that allows the planar integration of optical waveguides inside the glass core material and the light transmission through the carrier between different optical layers. This paper presents a four channel bi-directional o ptoelectronic transceiver module that was designed and processed using the glass carrier based packaging approach called glassPack. The transceiver operates with 10 Gbps per channel and has an extremely low power consumption of 592 mW. The module is mounted on a printed circuit test board and the performance is characterized by bit error rate testing

Single-mode board-level interconnects for silicon photonics

An optical interconnection technology for 1310/1550nm has been successfully developed with single-mode glass waveguide panels characterizes loss of 0.05dB/cm. The glass has been integrated into a multi-layer electrical printed circuit board for silicon photonic assembly

Planar polymer and glass graded index waveguides for data center applications

Embedded optical waveguide technology for optical printed circuit boards (OPCBs) has advanced considerably over the past decade both in terms of materials and achievable waveguide structures. Two distinct classes of planar graded index multimode waveguide have recently emerged based on polymer and glass materials. We report on the suitability of graded index polymer waveguides, fabricated using the Mosquito method, and graded index glass waveguides, fabricated using ion diffusion on thin glass foils, for deployment within future data center environments as part of an optically disaggregated architecture. To this end, we first characterize the wavelength dependent performance of different waveguide types to assess their suitability with respect to two dominant emerging multimode transceiver classes based on directly modulated 850 nm VCSELs and 1310 silicon photonics devices. Furthermore we connect the different waveguide types into an optically disaggregated data storage system and characterize their performance with respect to different common high speed data protocols used at the intra and inter rack level including 10 Gb Ethernet and Serial Attached SCSI

Thin glass based electro-optical circuit board (EOCB) with through glass vias, gradient-index multimode optical waveguides and collimated beam mid-board coupling interfaces

First time an electro-optical circuit board (EOCB) is demonstrated with integrated planar multimode glass waveguide panel and out-of plane spherical mirror based coupling elements. Such EOCBs will be needed in upcoming high performance computers and data storage network environments. Light from 850 nm up to 1550 nm can be directly coupled from the optical engine mounted mid-plane on the EOCB and coupled into low loss optical waveguides for signal transmission. The demonstration platform comprises a multilayer EOCB with 1301 electrical through glass vias (TGVs), two embedded thin glass layers, planar integrated gradient-index multimode glass waveguides and mid-board optical coupling interface. The evaluated demonstrator system performed with insertion loss of 1.94 dB at wavelength of 850 nm for link distance of 7.1 cm. In best case without misalignment the out-of plane coupling loss is 3.5 dB

Involvement of metabotropic glutamate 5 receptor in visceral pain

Metabotropic glutamate 5 receptor (mGluR5) antagonists are effective in animal models of inflammatory and neuropathic pain. The involvement of mGluR5 in visceral pain pathways from the gastrointestinal tract is as yet unknown. We evaluated effects of mGluR5 antagonists on the colorectal distension (CRD)-evoked visceromotor (VMR) and cardiovascular responses in conscious rats, and on mechanosensory responses of mouse colorectal afferents in vitro. Sprague-Dawley rats were subjected to repeated, isobaric CRD (12 x 80 mmHg, for 30s with 5 min intervals). The VMR and cardiovascular responses to CRD were monitored. The mGluR5 antagonists MPEP (1-10 micromol/kg, i.v.) and MTEP (1-3 micromol/kg, i.v.) reduced the VMR to CRD dose-dependently with maximal inhibition of 52+/-8% (p<0.01) and 25+/-11% (p<0.05), respectively, without affecting colonic compliance. MPEP (10 micromol/kg, i.v.) reduced CRD-evoked increases in blood pressure and heart rate by 33+/-9% (p<0.01) and 35+/-8% (p<0.05), respectively. Single afferent recordings were made from mouse pelvic and splanchnic nerves of colorectal mechanoreceptors. Circumferential stretch (0-5 g force) elicited slowly-adapting excitation of action potentials in pelvic distension-sensitive afferents. This response was reduced 55-78% by 10 microM MTEP (p<0.05). Colonic probing (2g von Frey hair) activated serosal splanchnic afferents; their responses were reduced 50% by 10 microM MTEP (p<0.01). We conclude that mGluR5 antagonists inhibit CRD-evoked VMR and cardiovascular changes in conscious rats, through an effect, at least in part, at peripheral afferent endings. Thus, mGluR5 participates in mediating mechanically evoked visceral nociception in the gastrointestinal tract.Erik Lindström, Mikael Brusberg, Patrick A. Hughes, Christopher M. Martin, Stuart M. Brierley, Benjamin D. Phillis, Rakel Martinsson, Christina Abrahamsson, Håkan Larsson, Vicente Martinez, L. Ashley Blacksha