Abstract
The objective of the current work has been to develop a system which will allow continuous monitoring of areal mass density, lateral stress, and temperature during a process with real time presentation of results making possible either manual or automated control of the process. The system uses three quartz resonators of different crystallographic cuts (AT cut, BT cut and SC cut) in the same environment. The development of an algorithm to solve a system of equations representing a complete representation of the temperature characteristics of the three resonators is presented. This is followed by an analysis of the potential accuracy of the system and the limitations imposed by the assumptions made in the mathematical models of the system. Sputtering yields were verified using Rutherford backscattering analysis. Experimental apparatus including the physical mounting of the resonators in an experimental environment, details of the oscillator circuitry and frequency counter, and use of a personal computer for data acquisition and control are described. The results presented show, in addition to the mass change and lateral stress build-up which occur when sputtering a gold film with an argon ion beam, the radiation induced temperature rise and the radiation induced stress caused by temperature gradients. An experiment using beams of Sb+ at 50keV and Sb2+ at 100keV has been used to demonstrate the enhancement of sputtering yield that occurs when Au films are bombarded with monomers and dimers of Sb at the same energy per atom. Results are compared with simulations using both the TRIM program and molecular dynamics code.