Selective, low-temperature chemical vapor deposition of gold

A chemical-vapor-deposition method for selectively depositing gold onto a catalytically-activated region on a surface of a workpiece in the presence of a catalytically-inactive region on the surface, comprising the steps of:

• (a) placing the workpiece in a vacuum chamber, a surface of the workpiece defining a target surface;
• (b) evacuating the vacuum chamber to a base pressure equal to or less than a catalyst-activity-preserving upper pressure limit to eliminate effectively gaseous catalyst-deactivating contaminants from the vacuum chamber;
• (c) altering the surface composition of at least one region of the target surface to produce a catalytically-activated region on the target surface, at least one region of the target surface disjoint from the catalytically-activated region being a catalytically-inactive region;
• (d) introducing a gaseous gold-containing compound into the vacuum chamber to expose the target surface of the workpiece to the compound, the compound being an alkylate (trialkylphosphine) gold compound;
• (e) essentially continuously evacuating the vacuum chamber during exposure of the target surface to the gold-containing compound to maintain the vacuum chamber effectively free of gaseous catalyst-deactivating contaminants and to sweep gaseous reaction products from the vacuum chamber, the vacuum chamber being maintained effectively free of gaseous reducing agents during exposure of the target surface to the gold-containing compound;
• and
• (f) maintaining the target surface of the workpiece at a selective-deposition temperature effective to induce the gaseous gold-containing compound to deposit gold on the catalytically-activated regions of the target surface and to inhibit the compound from depositing gold on the catalytically-inactive regions of the target surface subsequent to altering the surface composition of at least one region as the target surface to produce a catalytically activated region in step (c) and prior to introducing the gaseous gold-containing compound into the vacuum chamber in step (d), introducing a gaseous reversible-catalysts-inhibition agent into the vacuum chamber to expose the target surface of the workpiece to the agent to inhibit the catalytic activity of at least a portion of the catalytically activated region.