Organic–inorganic hybrid materials do not represent only a creative alternative to design new materials and compounds for academic research, but their improved or unusual features allow the development of innovative industrial applications. Nowadays, most of the hybrid materials that have already entered the market are synthesised and processed by using conventional soft chemistry based routes developed in the eighties. These processes are based on: a) the copolymerisation of functional organosilanes, macromonomers, and metal alkoxides, b) the encapsulation of organic components within sol–gel derived silica or metallic oxides, c) the organic functionalisation of nanofillers, nanoclays or other compounds with lamellar structures, etc. The chemical strategies (self-assembly, nanobuilding block approaches, hybrid MOF (Metal Organic Frameworks), integrative synthesis, coupled processes, bio-inspired strategies, etc.) offered nowadays by academic research allow, through an intelligent tuned coding, the development of a new vectorial chemistry, able to direct the assembling of a large variety of structurally well defined nano-objects into complex hybrid architectures hierarchically organised in terms of structure and functions. Looking to the future, there is no doubt that these new generations of hybrid materials, born from the very fruitful activities in this research field, will open a land of promising applications in many areas: optics, electronics, ionics, mechanics, energy, environment, biology, medicine for example as membranes and separation devices, functional smart coatings, fuel and solar cells, catalysts, sensors, etc.

Applications of hybrid organic–inorganic nanocomposites

Today cross-cutting approaches, where molecular engineering and clever processing are synergistically coupled, allow the chemist to tailor complex hybrid systems of various shapes with perfect mastery at different size scales, composition, functionality, and morphology. Hybrid materials with organic–inorganic or bio–inorganic character represent not only a new field of basic research but also, via their remarkable new properties and multifunctional nature, hybrids offer prospects for many new applications in extremely diverse fields. The description and discussion of the major applications of hybrid inorganic–organic (or biologic) materials are the major topic of this critical review. Indeed, today the very large set of accessible hybrid materials span a wide spectrum of properties which yield the emergence of innovative industrial applications in various domains such as optics, micro-electronics, transportation, health, energy, housing, and the environment among others (526 references).

Applications of advanced hybrid organic–inorganic nanomaterials: from laboratory to market

A simple fabrication method for multimode polymer optical waveguides with graded-index (GI) circular cores is introduced for use in optical printed circuit boards (O-PCBs). The new method, named “Mosquito method,” utilizes a microdispenser to dispense a viscous monomer directly onto the substrates. By optimizing the dispensing conditions, 12-channel parallel waveguides with circular GI-cores (core diameter of 40 μm) are successfully fabricated using the Mosquito method. The advantages of GI-core waveguides for O-PCB applications are discussed by comparing the optical characteristics of the fabricated waveguides with those of conventional step-index (SI) square-core polymer waveguides, and even with those of silica-based GI multimode fibers (MMFs), as an ideal case. To the best of our knowledge, this is the first comparison of SI- and GI-core multimode polymer waveguides that are composed of the same polymer materials and that have similar core and pitch sizes. We experimentally demonstrate that the GI circular-core polymer waveguides fabricated by the Mosquito method have sufficiently low propagation loss (0.033 dB/cm at 850 nm), low connection loss with GI-MMFs, and low interchannel crosstalk. We observe approximately -50 dB of interchannel crosstalk in the 250-μm pitch GI-core waveguide fabricated, which is almost 10 dB lower than in the SI counterpart. Furthermore, sufficiently low crosstalk is maintained in a half-pitch GI-core waveguide fabricated by the Mosquito method.

Fabrication of a Graded-Index Circular-Core Polymer Parallel Optical Waveguide Using a Microdispenser for a High-Density Optical Printed Circuit Board

Organic–inorganic hybrid materials towards passive and active architectures for the next generation of optical networks

N Integrated optical systems require waveguides that can route light along defi ned pathways with minimal losses and negligible crosstalk. [ 1–3 ] In addition to signal transmission, optical waveguides play an important role in the area of sensing. For example, evanescent fi eld sensors are applied to the detection of analytes in the body, [ 4 ] atmosphere, [ 5 ] and liquid solutions. [ 6 ] Polymeric and hybrid materials are of increasing interest for these applications due to their low temperature processing. [ 7 ] To date, channel waveguides have been fabricated by direct lithographic patterning, [ 8 , 9 ] photoresist-templated etching, [ 10 ] or soft-lithographic approaches. [ 11 , 12 ] However, these techniques are limited either to in-plane confi gurations or require repeated developing or etching steps to produce multiple layers of waveguides. Those processing steps often have a deleterious effect on waveguide performance, leading to rough edges and, hence, higher optical loss. [ 8 , 11 , 13 ]

Photocurable liquid core-fugitive shell printing of optical waveguides

A flexible approach to producing optical interconnects on 6096 $ast ,$ 6096 mm large-area panels is demonstrated Stepwise projection patterning from 1016 $ast ,$ 1016 mm masks has generated optical waveguide patterns over the whole panel using large-area projection lithography equipment The waveguide routing design allows optical waveguides on different 1016 $ast ,$ 1016 mm tiles to be interconnected Four different waveguide connecting geometries in the border region between tiles have been fabricated and tested Multimode waveguides from inorganic-organic hybrid polymers (ORMOCER) (cross section: $le hbox 50~muhbox mast hbox 10~muhbox m$ ) with refractive index step between core and cladding $Delta n=hbox 001$ were produced The index step was adjusted by mixing two diffrent ORMOCER systems The materials show good adhesion to numerous substrates, such as glass and silicon Application concepts such as flexible manufacturing of optoelectrical hybrid backplanes with two-dimensional interconnect, a three-dimensional optical interconnect with optical vias, and a hybrid backplane with the optical interconnect in a strip-format on a separate plane right above the electrical plane are proposed Promising new technologies are presented along with preliminary demonstrativ viability

Polymer Optical Interconnects&#8212;A Scalable Large-Area Panel Processing Approach

Requirements of higher performance, reduced size, weight and cost of high-frequency (HF) devices has led to the search for new: materials, material combinations, methods, processes and production equipment. Efficient technologies for producing HF-circuits and integral passives are looked for. Also of interest are integrated packaging solutions for high frequency electrical packaging and optical interconnects and packaging. Sequentially build up multi-layers have been deposited on a low cost FR-4 epoxy substrate. The dielectric layers consist of a photo-patternable inorganic-organic hybrid polymer (ORMOCER) and the metallization is Cu. An UV-exposure equipment enabling projection patterning with 5 /spl mu/m resolution have been used. The produced microstrip lines, ring resonators, vias, stacked capacitors and filters have been characterized at frequencies from 1 to 40 GHz showing the potential of the new dielectric materials and processing technologies for microwave applications.

Microwave circuits in multilayer inorganic-organic polymer thin film technology on laminate substrates

Upon processing waveguide structures by using the ORMOCER materials ORMOCORE as core material, and a mixture of ORMOCORE and ORMOCER-III (refractive index tuning agent) as cladding material, dewetting effects of the core layer from the cladding layer were observed. A similar phenomenon was observed for a mixture of ORMOCORE and ORMOCLAD which was used as comparative refractive index tuning material. In order to use these material combinations for large-area panel (LAP) processing, a pretreatment or activation of surfaces is necessary but hard to realize. However, the addition of small amounts of ORMOCER-III or ORMOCLAD, respectively, to the core layer material, prevented the dewetting phenomenon. The objective of this, however, is to minimize the content of refractive index tuning agent in the core layer by retaining a good wetting behavior during multilayer processing. Wet film stability tests and contact angle measurements of these ORMOCER systems in various compositions on another ORMOCER surface of a specific cladding material composition were performed on a hotplate. Furthermore, contact angles of droplets formed by deionized water, formamide, and di-iodomethane on cured surfaces of these ORMOCER systems in a wide range of compositions were characterized, and surface tensions were calculated. By adding 0.1 wt% of ORMOCER-III or 5 wt% ORMOCLAD, respectively, to the pure ORMOCORE solution, the dewetting phenomenon was eliminated, while simultaneously the refractive index was affected only to a minor degree and no changes in the optical loss could be detected. It was shown that by adding ORMOCER-III or ORMOCLAD to pure ORMOCORE, the surface tension of the compound system was reduced. In comparison to silanization or gasplasma treatment to overcome dewetting effects in microelectronics multilayer processing, the investigated mixing method eliminates process steps and thus costs, and opens new process routes for LAP processing

L. Frohlich

Papers

Polymer Optical Interconnects—A Scalable Large-Area Panel Processing Approach

Microwave circuits in multilayer inorganic-organic polymer thin film technology on laminate substrates

Preventing of Dewetting Effects for Inorganic–Organic Hybrid Polymers Applied in Sequentially Buildup (SBU) Technology Without Surface Pretreatments

L. Frohlich

Papers

Polymer Optical Interconnects&#8212;A Scalable Large-Area Panel Processing Approach

Microwave circuits in multilayer inorganic-organic polymer thin film technology on laminate substrates

Preventing of Dewetting Effects for Inorganic–Organic Hybrid Polymers Applied in Sequentially Buildup (SBU) Technology Without Surface Pretreatments

Polymer Optical Interconnects—A Scalable Large-Area Panel Processing Approach