Electroless Cu plated AlN substrate

The metallization of AlN substrates by electroless Cu plating is investigated. Four-percent NaOH aqueous solution is employed as the chemical etchant before plating to study the correlation between the surface roughness and the adhesion strength of the etched substrates. Mechanical interlocking is suggested to be the major cause of the adhesion strength between the Cu and AlN substrate. Adhesion strength as high as 271 kg/cm² is obtained for a polished-and-etched sample. The adhesion strength of the electroless Cu on the AlN substrate increases if the surface roughness of the AlN substrate is enhanced. The interfacial morphology of the Cu-plated AlN substrate is investigated and the adhesion mechanism is explored