Experimental Performance Analysis of Fabricated Si/Ge Thin Film Structure

Abstract

This paper is devoted to the evaluation of a Silicon/Germanium (Si/Ge) thin film structure based on experimental measurements. An electron beam evaporator was used to fabricate
this structure. The sample was prepared under high vacuum conditions (pressure of 10-5 Torr, power of 6 kV and current of 200 mA). At these conditions, it was possible to get films with thickness of approximately 300 Å. The capacitance–voltage (C–V) and current–voltage (I–V) measurements of the sample were performed by a staircase sweep of voltages from 0 to 5 V and back from 5 to 0 V at room temperature. The sample exhibits a low hysteresis in measurements; this hysteresis is gradually removed when the sample is exposed to temperatures until 80 °C using a Carbolite Oven. It is also observed that both C-V and I-V characteristic curves of the sample has been smoothened. This sample exhibits an electroforming behavior as a metal-oxide-semiconductor (MOS) device over a short time duration of the selected staircase double sweep, hence it can be exploited as a fast switching element in digital microelectronic circuits. In addition, the hysteresis changes over the range from room temperature until 80 °C have opened the door to the possibility of exploiting this sample as a proximity temperature sensor within that range of temperature.