Focused ion beam deposition of Pt containing films

Abstract

Focused ion beam induced deposition of platinum films from a gas of methylcyclopentadienyl trimethyl platinum is reported. Deposition was carried out with a 25 kV beam of Ga+ with current densities of 2–7 A/cm2 that was controlled by a digital scan generator. Film yields and resistivity were measured as a function of beam current density, gas flux, scan dwell, and loop time. Relatively high yields of 1.4 μm3/nC and resistivities as low as 400 μΩ cm were measured for deposition carried out in 1×10−6 Torr background pressure of residual gas. Auger studies revealed that the films were surprisingly free of oxygen, but contained significant amounts of carbon. A figure-of-merit, Fm=ρ/Y, is defined which enables comparison of films used for interconnects. Fm for the Pt films is superior to that of W(CO)6 deposited W films.