AVS 45th International Symposium
    Applied Surface Science Division Monday Sessions
       Session AS-MoP

Paper AS-MoP3
Total Sputtering Yield of Ag/Cu Alloys Versus Composition and Temperature for 260 eV Ar+

Monday, November 2, 1998, 5:30 pm, Room Hall A

Session: Aspects of Applied Surface Science Poster Session
Presenter: K.W. Pierson, University of Wisconsin, Eau Claire
Authors: K.W. Pierson, University of Wisconsin, Eau Claire
C.D. Hawes, University of Wisconsin, Eau Claire
M.S. Vogel, University of Wisconsin, Eau Claire
N.C. Harris, University of Wisconsin, Eau Claire
P.J. Gustafson, University of Wisconsin, Eau Claire
G.C. Falkenberg, University of Wisconsin, Eau Claire
Correspondent: Click to Email
The results of recent sputtering yield experiments have important implications concerning depth profiling of the Ag/Cu alloy system. The total sputtering yield of a range of Ag/Cu alloy compositions for various target temperatures has been measured for normally incident 260 eV Ar+ and a dose of 5.4x10@super 19@ ions/cm@super 2@. At temperatures between -50 C and +40 C the yield of all compositions between 20/80 (% atomic Ag/Cu) and 80/20 is approximately equal to pure Cu. For targets with an increased Ag percentage above 80/20 the yield climbs toward the value of pure Ag. At temperatures above 40 C, micron size cones develop on the target surface and the yield decreases dramatically in an unpredictable manner due to redeposition of ejected material. We hypothesize that the relatively sharp transition to cone development is due to the exponential nature of surface diffusion, which is believed to be necessary for cone develoopment. The low transition temperature to cone development and unpredictable yields is important for depth profiling, as these temperatures are easily attainable for improperly heat-sinked targets, high ion energy, or high ion beam flux. The fact that yield of a large range of compositions becomes approximately equal to pure Cu at low temperatures for properly heat-sinked targets is important for predicting depth scales.