A method of selectively depositing a metal on a surface is disclosed. The method comprises selectively coating a surface with a surface active agent, having a first surface energy, to form a coated surface having a coated portion capable of burying a higher surface energy material applied thereto and an uncoated surface pattern not so capable. The selectively coated surface is then treated with a solution, having a second surface energy higher than the first, comprising a species selected from the group comprising (1) a species capable of reducing an activating metal ion to an activating metal and (2) an activating metal species capable of participating in an electroless metal deposition, to form a surface having the species deposited atop the uncoated pattern.
To metallize a preferably glass-like body with good adhesion of the metal, the glass-like body is coated with a thin layer of an indium-tin alloy, whereupon a catalytic germination layer is produced for currentless chemical metal precipitation by reducing a catalyst metal compound to the catalyst metal directly by the indium-tin layer or after the indium-tin layer has been reacted by salt formation or hydrolysis. After currentless chemical metallization, reinforcement may continue by electroplating with conventional metals.
Structures and methods of fabrication thereof wherein the method selectively supplies electrons to a first electroactive material in the presence of a second electroactive material wherein the first and second electroactive materials have different redox potentials. The electrons are selectively supplied either by electrochemical means or by appropriately chosen reducing agents. A structure fabricated by these methods has a first electroactive body disposed on a second electroactive body wherein the first body has a pattern therein exposing at the base thereof the surface of the second electroactive material body. Electrons can be selectively supplied to the surface of the second electroactive material body which is exposed at the base of the pattern in the first electroactive material body. Upon exposing the structure to a seeding solution seed is selectively supplied to those regions to which electrons have been selectively supplied. Electrically conductive material can then be electrolessly deposited onto the seed material to form an electrically conductive pattern in the pattern in the first electroactive body. The electroactive material bodies are preferably polyimide materials. The structures can be used as the top metallization levels of an electronic device such as a semiconductor chip or a semiconductor chip packaging substrate.
A thin film device having a selectively passivated surface is provided. An embodiment of the device is particularly suited to detection of chemical constituents by selective adsorption, where the selectively passivated surface is inert to the chemical constituent being detected. A method of fabrication of the device is also provided in which the selective passivation is achieved by selectively applying the metallic adhesive to the substrate. The migration of the metallic adhesive through the thin film layer is essentially normal to the surface of the substrate, thereby limiting the passivation of the thin film layer to the surface areas directly overlying the metallic adhesive.
A method of increasing the hydrophobicity of solid materials. The inventive method comprises the steps of: (a) metal ion activating the surface of a solid substrate material to provide reactive metal sites on the surface and (b) chemically bonding a surfactant to the surface at the reactive metal sites. Titanium dioxide pigments and other particulate property modifiers treated in accordance with the inventive method are more readily dispersed in polymer compositions.
A process for the metallization of a plastic by electroless deposition, wherein the plastic surface is contacted with a solution useful for the treatment of oxidant residue following contact of the surface with an oxidizing solution such as a hexavalent chromium or permanganate solution. In one embodiment, the solution comprises a reducing agent, a pH adjuster and a surface active agent in a concentration sufficient to reduce the surface tension of the solution preferably to 50 dynes per square centimeter or less at the operating temperature of the solution. In a second embodiment, the solution consists essentially of the surface active agent in a concentration sufficient to achieve the above surface tension range.