AVS 45th International Symposium
    Thin Films Division Monday Sessions
       Session TF-MoP

Paper TF-MoP19
Investigation of Ti and Cu Atom Density in Magnetron Sputtering Process Using Atomic Absorption Spectroscopy

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

Session: Thin Films Poster Session
Presenter: E. Augustyniak, Intelligent Sensor Technology
Authors: E. Augustyniak, Intelligent Sensor Technology
S.V. Filimonov, Intelligent Sensor Technology
C. Lu, Intelligent Sensor Technology
Correspondent: Click to Email
A hollow cathode lamp based atomic absorption monitor is applied to measure the relative atom density in a planar DC magnetron sputtering system for various Argon pressures (from 1 to 30 mTorr) and input powers (from 0.3 to 20 W/ cm@super 2@). Deposition rates for Ti and Cu are monitored with a piezoelectric microbalance in order to infer the absolute atom densities. Absorption versus deposition data obtained from thermal evaporation of the same materials at Argon pressures in the range from 10@super -6@ to 10@super -3@ Torr are used to estimate the degree of thermalization in sputtering process. Near the target, at distance shorter than one mean-free path of sputtered atoms, the film grows mostly due to deposition of energetic atoms. However, even in this region the thermalized atoms have a significant contribution to the total absorption of resonant radiation. The experimental data show that the reduction of local number density caused by the introduction of a nearby sink for sputtered atoms, e.g., a substrate or a sensor, can be as much as 50%. Ambient gas heating in the vicinity of the target at high input power results in suppressed thermalization and decreased sensitivity of atomic absorption. The combination of atomic absorption spectroscopic and gravimetric (by piezoelectric microbalance) measurements can be a powerful tool for sputtering process characterization.