Impedance Response and Phase Angle Determination of Metal-Semiconductor Structure with N-Doped Diamond Like Carbon Interlayer

Abstract

With their superior properties over p-n barriers, Schottky Barrier Diodes have a wide usage area, especially as a test tool to produce better-performance devices. The main performance parameter of these devices is measured by their conduction, which can develop with an interlayer addition through the sandwich design. Regarding the DLC, which also has outstanding specifications under thermal, chemical, and physical conditions, is a good candidate for interlayer tailoring, specifically when used with doping atoms. Thus, this study investigates the impedance response of the fabricated device with an N-doped DLC interlayer by employing the electrochemical technique as a combination of electrolysis, RF magnetron sputtering, and thermal evaporation. The measurements were conducted for broad scales of voltage and frequency corresponding between (-3V) and (+4V) and 1kHz and 1MHz, respectively. According to the impedance analysis, complex impedance decreases by rising bias and frequency, from 1.8 MΩ to 2 k Ω at 1MHZ due to the additional insulating layer. At the same time, the phase angle indicates the quality of the dielectric layer with an average of 81.36  for the sample logarithmic frequency values with an almost constant-like trend in the inversion stage. In comparison, it reduces to an average of 30.25  after the depletion stage by showing the rising conductivity. Moreover, it has some unexpected rising values at the strong accumulation stage, possibly due to the deposited thin film's unique structure. The supported results by phase angle changes, showing frequency-adjustable working conditions, may offer that selective electrical conduction can be tuned.