INTRINSIC RESPUTTERING - THEORY AND EXPERIMENT

This study examines a type of resputtering that attends the deposition of sputtered materials under elementary conditions—sputtering with a single ion beam at pressures below 0.01 Pa. Ne, Ar, Kr, and Xe were employed to sputter nine simple metals ranging in mass from Al to Au. Comparative weight gains on planar and concave substrates revealed the magnitude of resputtering, which varied from about 3.5% for light metals sputtered with heavier ions to over 20% for gold sputtered with neon. The results define a universal curve that appears constant at mass ratios less than unity but increases steeply beyond a mass ratio intercept slightly greater than unity. A theoretical analysis is developed that predicts the striking universality, relates the observed intercept to the existence of finite sputtering threshold energies, and fits the full range of experimental data with one adjustable parameter having a derived value of unity. © 1990, American Vacuum Society. All rights reserved.