NONSELECTIVE COPPER FILM GROWTH ON KAPTON (POLYIMIDE) BY MOCVD

High-purity polycrystalline Cu films have been deposited for the first time on a commercial polyimide using thermal, cold-wall, reduced-pres sure (20 Torr) MOCVD. Two precursors were employed; Cu(acac)(2) and Cu (HFA)(2). The deposition temperature ranged from 275 to 425 degrees C and the source temperature ranged from 85 to 150 degrees C depending o n the source involved. The reaction proceeded with and without the hel p of H2O vapor. When H2O was used, the film growth rate was up to 420 Angstrom min(-1) and grain sizes up to 1.5 mu m were obtained in the c ase of the Cu(HFA)(2) source. H2O significantly increased the growth r ate in the case of the Cu(acac), source. When H,O was not used, with e ither source, the grain size was smaller (0.7-1.1 mu m) and the films were physically more optically reflective. In the first few minutes of the deposition, the deposited film consisted entirely of the copper o xide phase. As the reaction continued, pure Cu films were obtained. Th e films were characterized using XRD, LVSEM, SAXPS and RBS. Electrical resistivity of 3.25 mu Omega cm was measured for films prepared with deposition temperatures of 420 degrees C and in the presence of H2O va por. Simple Scotch-tape adhesion tests revealed qualitatively that the deposited films adhere well to the polyimide substrate.