Analysis of Hopping Conduction and Space Charge Limited Currents in Nearly Ideal Metal/Semiconductor Contacts

Abstract

We have formed a nearly ideal Au/n-Si Schottky contact and deposited gold (Au) metal on n-Si (100) using thermally evaporation method for an explanation of space charge limited current (SCLC) from current-voltage (I-V) characteristic, interface trap density from capacitance-conductance-voltage (C-G-V) characteristics and hopping conduction from conductance-frequency (G-f) characteristic in nearly ideal metal/semiconductor contacts. The device showed good intimate rectifying behavior. To observe the SCLC mechanism and determine interface trap density of the sample, the log (I)−log (V) and C-G-V characteristics are plotted. The interface trap density values for low frequency (5 kHz) and high frequency (1 MHz) are determined as 4.98 x 1014 eV-1 cm-3 and 7.81 x 1012 eV-1 cm3, respectively. At the same time the main diode parameters such as ideality factor and barrier height are determined as 1.048 and 0.807 eV, respectively. These diode parameters refer a nearly ideal metal-semiconductor contact.