Planar inorganic device

Abstract

A method for making an inorganic structure including: (a) applying a photoreactive composition to a substrate, wherein the composition includes: a reactive species, a photoinitiator system, and a plurality of substantially inorganic colloidal particles, wherein the particles have an average particle size of less than about 300 nm; (b) photopatterning the composition to define a structure; and (c) subjecting the structure to elevated temperature for a time sufficient to pyrolyze the reactive species and to at least partially fuse the particles.

1 . A photoreactive composition comprising: 
 (a) an organic reactive species,    (b) a photoinitiator system; and    (c) a plurality of substantially inorganic colloidal particles, wherein the particles have an average particle size of less than about 300 nm and are present in the composition at less than about 65% by volume, wherein the composition has a viscosity of greater than 15,000 centipoise at room temperature and a shear rate of 1 Hz.    
   
   
       2 . The composition of  claim 1 , wherein the reactive species is selected from the group consisting of acrylates, methacrylates, vinylates, epoxies, vinyl ethers, cyanate esters, and copolymers and blends thereof.  
   
   
       3 . The composition of  claim 1 , wherein the photoinitiator system comprises free-radical or cationic photoinitiators, and combinations thereof.  
   
   
       4 . The composition of  claim 3 , wherein the cationic photoinitiator is selected from the group consisting of iodonium salts, chloromethylated triazines, diazonium salts, sulfonium salts, azinium salts, triarylimidazolyl dimers, and mixtures thereof.  
   
   
       5 . The composition of  claim 3 , wherein the free-radical photoinitiator is selected from the group consisting of acetophenones, benzophenones, aryl glyoxalates, acylphosphine oxides, benzoin ethers, benzil ketals, thioxanthones, aromatic sulfonyl chlorides, photoactive oximes, nitroso compounds, acyl halides, hydrozones, chloroalkyltriazines, bisimidazoles, triacylimidazoles, pyrylium compounds, sulfonium and iodonium salts, mercapto compounds, quinones, azo compounds, and organic peroxides.  
   
   
       6 . The composition of  claim 3 , wherein the photoinitiator system further comprises a photosensitizer and an electron donor compound.  
   
   
       7 . The composition of  claim 1 , wherein the particles are surface-treated.  
   
   
       8 . The composition of  claim 7 , wherein the surface treatment method is selected from the group consisting of silanization, plasma treatment, organic acid treatment, Corona treatment, hydrolysis, coating, and titanation.  
   
   
       9 . The composition of  claim 1 , wherein the particles comprise surface attached organic groups.  
   
   
       10 . The composition of  claim 1 , wherein the particles are substantially spherical.  
   
   
       11 . The composition of  claim 1 , wherein the particles are present in the composition at between about 50% and about 80% by weight.  
   
   
       12 . The composition of  claim 1 , wherein the particles are substantially monodisperse in size.  
   
   
       13 . The composition of  claim 1 , wherein the particles are substantially bimodal in size distribution.  
   
   
       14 . The composition of  claim 1 , wherein the particles have an average particle size from about 1 nm to about 150 nm.  
   
   
       15 . The composition of  claim 1 , wherein the colloidal particles comprise a metal oxide.  
   
   
       16 . The composition of  claim 15 , wherein the metal oxide is selected from the group consisting of silica, titania, alumina, zirconia, vanadia, antimony oxide, tin oxide, and combinations thereof.  
   
   
       17 . The composition of  claim 1  further comprising a doping agent.  
   
   
       18 . The composition of  claim 17 , wherein the doping agent is selected from the group consisting of metal salts, fluxing agent, dyes, sol-gel precursors, organometallic precursors, and combinations thereof.  
   
   
       19 . The composition of  claim 18 , wherein the fluxing agent comprises boron oxide, boric acid, borax, and sodium phosphate.  
   
   
       20 . An epoxy formulation comprising: 
 (a) an epoxy resin,    (b) a photoinitiator system; and    (c) a plurality of substantially inorganic colloidal surface-treated silica particles, wherein the particles have an average particle size of less than about 300 nm, and wherein the formulation has a viscosity of greater than 15,000 centipoise at room temperature and a shear rate of 1 Hz.    
   
   
       21 . The formulation of  claim 20 , wherein the particles are substantially spherical.