Catherine Mallardeau

Effect of sputter-etching conditions on the barrier characteristics and the process-induced defects in (Ti-W)/Si Schottky diodes

Abstract The effects of argon sputter-etching conditions on the characteristics of (Ti-W)/Si (n-type) Schottky diodes have been studied. The etching rate ranged from 8 to 50 A min −1 and the time was adjusted so that a layer of 50–75 A was removed. The diode characteristics were determined by current-voltage and capacitance-voltage measurements, while deep-level transient spectroscopy was used to characterize the sputter-induced defects and to investigate theor dependence on backsputter-etching parameters. It was found that the barrier height of the devices strongly depends on the etching rate and time. Its value was maximum (about 0.6 V) for a sputter-etching rate near 20 A min −1 . Also several electron traps were measured in the upper half of the band gap. A trap situated at 0.36 eV from the conduction band edge was found in all the samples studied. The depth profiles of these traps were recorded. Theor concentrations varied by a factor of the order of 5 and depended on the etching conditions.

Electrical Properties and Sputter-etched Induced Defects in Ti-W/Si Schottky Diodes

Ti-W/Si (n type) Schottky diodecs which have been back-sputter etched prior to metal deposition are studied. It is found that the barrier height strongly depends on the etching conditions. Defects levels are measured usinig DLTS. Their characteristics are studied as function of the etching conditions.