Analysis of current–voltage and capacitance–voltage characteristics of Zr/p-Si Schottky diode with high series resistance

Abstract

Zr/p-Si Schottky diode was fabricated by DC magnetic sputtering of Zr on p-Si. Zr rectifying contact gave a zero bias barrier height of 0.73 eV and an ideality factor of 1.33 by current–voltage measurement. The experimental zero bias barrier height was higher than the value predicted by metal-induced gap states (MIGSs) and electronegativity theory. The forward bias current was limited by high series resistance. The series resistance value of 9840 [Formula: see text] was determined from Cheung functions. High value of the series resistance was ascribed to low quality ohmic contact. In addition to Cheung functions, important contact parameters such as barrier height and series resistance were calculated by using modified Norde method. Re-evaluation of modified Norde functions was realized in the direction of the method proposed by Lien et al. [IEEE Trans. Electron Devices 31 (1984) 1502]. From the method, the series resistance and ideality factor values were found to be as 41.49 [Formula: see text] and 2.08, respectively. The capacitance–voltage characteristics of the diode were measured as a function of frequency. For a wide range of applied frequency, the contact parameters calculated from [Formula: see text]–[Formula: see text] curves did not exhibit frequency dependence. The barrier height value of 0.71 eV which was in close agreement with the value of zero bias barrier height was calculated from [Formula: see text]–[Formula: see text] plot at 1 MHz. The values of acceptor concentration obtained from [Formula: see text]–[Formula: see text] curves showed consistency with actual acceptor concentration of p-Si.