Electroless metallization of diamond films

Abstract

Experimental studies of area selective metallization of diamond films are presented with emphasis on (i) laser activation of diamond surface for electroless metal plating, (ii) electroless metal deposition onto the activated surface areas, and (iii) diamond growth on the metal-patterned diamond films, encapsulating metal patterns into diamond. The activation of the diamond surface for electroless metal plating was achieved by laser-induced modification of the film surface during ablative etching. Transformations in the valence band structure of diamond upon laser processing were studied by Auger electron spectroscopy and related to a mechanism of activation of the diamond surface for electroless metal plating. It was concluded that the capability of laser-activated diamond surface to reduce metal ions from electroless solution was due to the formation of non-zero density of electronic states in the gap of diamond. Encapsulation of the electroless copper lines into diamond films was performed by means of the diamond growth onto the copper-plated diamond films. The composition and electrical properties of the encapsulated copper lines were studied, revealing high purity and low electrical resistivity of the encapsulated electroless copper.