The obtaining of Al-Ti10W90-Si(n) Schottky diodes and investigation of their interface surface states density

Electrical characteristics of Schottky diodes (SD) are rather sensitive to the state of the metal-semiconductor interface. For obtaining the amorphous metal film of a Ti10W90 alloy on a silicon substrate the magnetron sputtering method has been used. The microstructure of the films has been investigated using the X-ray method. The sandwich structure of Al-Ti10W90-Si(n) was obtained in a uniform work cycle. The diode matrix contained 14 diodes the areas of which changed from 1 X 10(-6) cm(2) to 14 x 10(-6) cm(2). For the study of the electrophysical parameters for the forward (I-f=I-s exp alpha V) and reverse (I-r =I-s exp alpha*V) current-voltage (I-V) characteristics in the temperature range of 300-458 K (alpha(max) = 37, 48 V-1 and alpha(max)* = 1-78 V-1, respectively) were measured. The analysis of the I V characteristics has shown that the surface states take part in a current transfer. Using the current-voltage characteristics the method of calculation of surface states distribution in the silicon band gap has been developed. The obtained surface states density and their energy distribution has shown the presence of discrete surface states characteristic for tungsten and silicide of titanium in the band gap of silicon. (c) 2007 Published by Elsevier Ltd.