Selective Copper Chemical Vapor Deposition Using Pd-Activated Organosilane Films

Conductive, adherent copper films were deposited selectively on diamond substrates using ligating aminosilane self-assembled films and a Pd-based catalyst. Copper chemical vapor deposition (CVD) was performed at 444-456 K in a cold-walled chamber using 4 x 10 -3 Pa of (hexafluoroacetylacetonato)-copper(I)-trimethylvinylsilane mixed 1 :1 (v/v) with H 2 carrier gas. In the absence of the Pd catalyst, only isolated copper particles deposited on hydrogenated or aminosilane-coated diamond. The Pd catalyst enhanced selectivity for Cu deposition by a factor of 10 3 to 10 4 . Copper patterns with feature sizes to 1 μm were formed by lithographically patterning an aminosilane film on diamond using UV (193 nm) radiation and a contact mask prior to catalyst deposition and copper CVD. The Pd catalyst also enhanced Cu deposition on aminosilane-coated Si(100) and quartz substrates. Treating substrates with octadecylsilane or aminosilane self-assembled films without the bound Pd catalyst reduced copper deposition compared to Si(100) native oxide or hydrogenated diamond surfaces.