Abstract: A method for forming semiconductor devices includes providing a substrate with a conductive pad formed thereon; forming a transparent structure over the substrate, wherein the transparent structure includes a plurality of collimating pillars adjacent to the conductive pad; forming a light-shielding structure over the plurality of collimating pillars and the conductive pad; performing a cutting process to remove one or more materials directly above the conductive pad, while leaving remaining material to cover the conductive pad, wherein the material includes a portion of the light-shielding structure; and performing an etching process to remove the remaining material to expose the conductive pad.

Abstract: This invention concerns a method for production of AlN powder. The reactants discovered in the invention are aluminum powder and a compound which contains NHx (e.g. NH2, NH3, NH4, N2H4, and N2H6 etc.) or halogens and which can be thermally decomposed or vaporized below the melting point of Al (660° C.). These two reactants are mixed at an appropriate ratio and then pressed into a compact with an appropriate shape. These two reactants, after being mixed at an appropriate ratio, may also be placed in a refractory container which has an opening at one end or has porous walls. In preparing the reactant compact or the reactant mixture, a dilutant such as AlN powder may also be added and mixed with the two reactants. This reactant compact or reactant mixture is then placed in a reaction chamber which is filled with nitrogen. By heating the reactant compact or the reactant mixture, the combustion synthesis reaction is ignited and AlN powder is produced.

Abstract: A method for preparing aluminium nitride includes a first step in which a mixture is formed of aluminium powder and ammonium halide powder. The mixture is then molded into a tablet, which is ignited in an airtight chamber containing nitrogen gas. Aluminium nitride is formed of the tablet through the combustion reaction of the tablet. The gas generated in the decomposition of the ammonium halide forms a number of channels in the tablet so as to enable nitrogen gas to enter the tablet to react with aluminium. The synthesis of aluminium nitride of high purity under low pressure is possible in view of the catalytic effect of the ammonium halide.