Abstract: A multilayer brazeable metallization structure for diamond components and method for producing it are described. The brazeable metallization finds particular application for the attachment of diamond components such as heat spreaders in electronic packages that incorporate high power semiconductor devices. In the present invention, a diamond component is provided with a multilayer coating of metals including depositing a first layer of chromium for adhesion onto at least a portion of the diamond component, depositing a second barrier layer of a refractory metal for a barrier onto at least portion of the chromium layer, and a top layer of copper, silver or gold for wetting. This top layer is thick (greater than 5 microns), without sacrificing resistance to delamination, particularly at brazing conditions. It is obtained by depositing a layer of a first metal onto at least a portion of the refractory metal layer, and depositing a layer of a second metal onto at least a portion of the first metal layer.
Abstract: This invention relates to the nature of thick film compositions that are specifically designed for the fabrication of circuit elements on diamond substrates, especially resistive elements. The nature of diamond sheet material requires special consideration because of its relatively low coefficient of thermal expansion and its sensitivity to oxygen at elevated processing temperatures. The general compositional requirements of thick film paste formulations are provided as a basis for accommodating the particular physical properties of diamond, and thereby establishing a method by which high performance microelectronic components can be fabricated economically. Thick film pastes containing certain borosilicate glasses, metal components, and optionally semiconducting materials are demonstrated to possess favorable behavior in terms of mechanical and electrical properties after sintering. Resistive elements on diamond can be fabricated by adding conductive components to a borosilicate glass.
Abstract: A multilayer brazeable metallization structure for diamond components is described. The brazeable metallization finds particular application for the attachment of diamond components such as heat spreaders in electronic packages that incorporate high power semiconductor devices. In the present invention, a diamond component is provided with a multilayer coating of metals including a first layer of chromium for adhesion, a second barrier layer of a refractory metal for a barrier that may be alloyed with chromium, and a top layer of copper, silver or gold for wetting. The refractory metals for the second layer include tungsten, molybdenum, tantalum and niobium. Tungsten or tungsten-chromium alloy is preferred as the second layer. This multilayer metallization structure provides a robust interface between diamond and standard brazing alloys which are used to join the diamond to electrical leads or a flange made of metals such as copper-tungsten.
Abstract: A unique Hall-Current ion source apparatus is used for direct ion beam deposition of DLC coatings with hardness values greater than 10 GPa and at deposition rates greater than 10 Å per second. This ion source has a unique fluid-cooled anode with a shadowed gap through which ion sources feed gases are introduced while depositing gases are injected into the plasma beam. The shadowed gap provides a well maintained, electrically active area at the anode surface which stays relatively free of non-conductive deposits. The anode discharge region is insulatively sealed to prevent discharges from migrating into the interior of the ion source. A method is described in which a substrate is disposed within a vacuum chamber, coated with a coating of DLC or Si-DLC at a high deposition rate using a Hall-Current ion source operating on carbon-containing or carbon-containing and silicon-containing precursor gases, respectively.
Type:
Grant
Filed:
July 11, 2000
Date of Patent:
January 7, 2003
Assignee:
Morgan Chemical Products, Inc.
Inventors:
Leonard Joseph Mahoney, David Ward Brown, Rudolph Hugo Petrmichl