Nanophase copper thin films deposited from a beam source

Although thin films formed from beams of nanoparticles or clusters: have be en discussed since the early 1970s, the question of the usefulness of this method has-remained open as few films of any significant thickness have bee n formed to date. Early attempts did not condense, could only condense a fe w "high vapor pressure" solids, or were so low rate as to make growth too s low to be of use. A new deposition system has been designed and built herea t Florida International University along the lines of those of Averback and Haberland, and they appear to have the most promise. The new system was sp ecifically designed for high rate with a high throughput, intermediate pres sure pump and 2 kW capable de sputter source. Optically transparent films h ave been deposited from a copper source but are not yet fully understood. F ilms were deposited onto single crystal silicon substrates and show a small beam divergence of less than 1 degrees total. The beam is highly nonunifor m with maximum intensity on ails, which drops rapidly to zero within less t han 10 mm off axis. Deposits have been made using a 1 Torr argon+helium spu ttering and condensation atmosphere followed by nozzle aperture extraction. Films are affected by the amount of He and by cooling of the sputter chamb er walls. (C) 1999 American Vacuum Society. [S0734-2101(99)13004-5].