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

Hybrid inorganic-organic polymers based on organically modified heteropolysiloxanes have found widespread attention and application as materials with adjustable properties using tailor-made precursors. The chemical structures of monomers and their modified sol-gel processing method are described. An overview is given for the control of various properties (mechanical, electrical, optical) of the materials on a molecular scale. Successful material developments and industrial applications are described.

Synthesis, properties and applications of inorganic-organic copolymers (ORMOCER®s)

Hybrid organic−inorganic materials have been obtained by cohydrolysis of (3-glycidoxypropyl)trimethoxysilane (GPTMS) and tetraethyl orthosilicate (TEOS) in acidic conditions. Boron trifluoride diethyl etherate (BF3OEt2) has been used to catalyze the epoxide polymerization. The effect of BF3OEt2 has been studied by multinuclear magnetic resonance (NMR) in the precursor sol and by Fourier transform infrared spectroscopy in the final material. The addition of BF3OEt2 to a prereacted sol of GPTMS and TEOS has allowed the epoxide ring opening at room temperature, without formation of diol units or boric acid precipitation in the final material. The prereaction time of GPTMS with TEOS has been found to be an important parameter. The catalytic effect of BF3OEt2 with respect to other commonly used catalysts in sol−gel processing of GPTMS-based hybrid organic−inorganic materials, such as zirconium butoxide and 1-methylimidazole, has been studied.

New Synthetic Route to (3-Glycidoxypropyl)trimethoxysilane-Based Hybrid Organic−Inorganic Materials

A composition for film formation which is capable of giving a silica-based coating film having an exceeding low dielectric constant and improved mechanical strength and useful as an interlayer insulating film in semiconductor devices and the like, a process for producing the composition, and a silica-based film obtained from the composition. The composition comprises (A) a product of hydrolysis and condensation obtained by hydrolyzing and condensing one or more silane compounds, and (B) an organic solvent.

Composition for film formation, method of film formation, and silica-based film

Hybrid polymers (ORMOCER ® s) with inorganic and organic structural units can be used to generate new functionalized coatings on a variety of substrates (ceramics, metals, polymers, etc.). By processing at temperatures below 150 °C, the formation of both inorganic and organic network structures using the sol–gel approach is possible. Due to the incorporation of special organic functional groups, important application related properties can be accomplished. ORMOCER ® lacquers can be processed by nearly all conventional coating techniques (dipping, spraying, spin on, etc.). The basic application fields for ORMOCER ® coatings are: • abrasion and scratch resistance, decoration; • barrier layers for packaging, corrosion resistant layers; • antisoiling, antifogging, antistatic and antireflective applications. In the past two years, the combination of ORMOCER ® layers with vapor deposited inorganic thin films (e.g. SiO x ) has been investigated, especially for barrier applications. Outstanding barrier properties were achieved, which show synergetic effects by using two different coating techniques together (wet chemical processing, vapor deposition).

Functionalized coatings based on inorganic–organic polymers (ORMOCER®s) and their combination with vapor deposited inorganic thin films

Inorganic-organic polymers with barrier properties against water vapor, excellent electrical data (e≤3, 2, RD>1016 Ωcm, ED up to 400 V/µm) and good adhesion to various substrate materials have been developed. Tailored modifications of these materials provide an excellent protective coating for thin film capacitors. Several mm thick, expensive, encapsulations could be replaced by thin coatings (up to 10 µm). The polymer coating allows the use of thin film chip capacitors in surface-mount technology. As a measure for the efficiency of the coating, the capacitance decrease under controlled humidity has been used. The influence of the material composition, the type of catalyst during sol-gel processing and the curing conditions have been studied. Adhesion and water vapor permeation properties of the polymers and rheological properties of the coating solutions have been investigated. A protective coating is developed, which increases the withstandness of capacitors against humid conditions (90°C, 100% rel. humidity) by a factor of about 30 (compared to uncoated capacitors) and shows no crack formation during thermal cycling.

A new inorganic-organic polymer for the passivation of thin film capacitors

The present invention relates to a lacquer obtained by the process comprising the steps of: (i) precondensation of: a) 1 to 10 mol % of at least one silane of the formula SiR4; b) 20 to 94 mol % of at least one organic silane of the formula R'm(R''Y)nSiX(4-m-n); c) 5 to 30 mol % of at least one organic silane of the formula R'pSiX4-p; d) optionally 0 to 10 mol % of at least one low-volatility metal oxide; and (ii) hydrolysis condensation of the precondensate of step (i) in the presence of the stoichiometric amount of water. The present invention also relates to a process for the obtention of a coating on substrates which comprises the steps of applying the lacquer and curing same. The invention also relates to the thus-coated substrates.

Silicon based lacquer, its use as a substrate coating and substrates thus obtained

New inorganic-organic copolymers (ORMOCERs – ORganically MOdified CERamics) were developed as protective coatings for electronic and optical devices, as patternable insulation and passivation layers for electronics, e. g. MCM's, and as possible interconnects and waveguides for micro optics. Depending on the chemical composition and the processing parameters, their important features are low permittivity constants (eR ≤ 3.2), high bulk resistance (RD > 1016 Ωcm), high dielectric strength (ED ≤ 400 V/μm), refractive index around 1.48, optical transparency in the range of 400 – 1300 nm, and good adhesion to numerous substrates, such as Al2O3, glass, silicon, copper, aluminum, steel, polyimides, polyesters and epoxides. The materials can be applied using standard technology. They are patterned by laser direct writing, photolithographic, screen printing or embossing technologies.

New Patternable Materials for Electronic Packaging

The present invention relates to a lacquer obtained by the process comprising the steps of: (i) precondensation of: a) 1 to 10 mol % of at least one zirconium compound of the formula ZrR 4 ; b) 20 to 94 mol % of at least one organic silane of the formula R" m (R'"Y) n SiX.sub.(4-m-n) ; c) 5 to 30 mol % of at least one organic silane of the formula R" p SiX 4-p ; d) optionally 0 to 10 mol % of at least one low-volatility metal oxide; and (ii) hydrolysis condensation of the precondensate of step (i) in the presence of 0 to 50% of the stoichiometric amount of water. The invention also relates to a process for the obtention of a coating on substrate which comprises the steps of applying the lacquer and curing same. The invention also relates to the thus-coated substrates.

Silicon and zirconium based lacquer, its use as a substrate coating and substrates thus obtained

Inorganic-organic copolymers (ORMOCERs - ORganically MOdified CERamics), synthesized by sol-gel processing, were developed for interconnection technologies and integrated optics. These optical transparent materials with excellent dielectric properties are patternable by standard technologies and, additionally, by laser direct writing.

Monika Pilz

Papers

A new inorganic-organic polymer for the passivation of thin film capacitors

Silicon based lacquer, its use as a substrate coating and substrates thus obtained

New Patternable Materials for Electronic Packaging

Silicon and zirconium based lacquer, its use as a substrate coating and substrates thus obtained

Patternable inorganic-organic copolymers (ormocers)