Carbon Thin Film on Silicon by Microwave Plasma

Abstract

This work aims to develop a low pressure microwave plasma deposition system to coat carbon thin film on silicon substrate. The system use a commercial microwave oven as a microwave source to get plasma discharge. The vacuum pressure was achieved by two stage rotary vane vacuum pump which is capable to reach ultimate pressure at 2×10-1 Pa under borosilicate chamber glass. The carbon thin films was successfully deposited on silicon substrate by pure acetylene plasma with gas flow rate 30 ml/min at total operating pressure of -70 cmHg reading by analog dial vacuum gauge, using microwave power at 1,200 Watts and deposit time at 150 seconds. Raman analysis showed peak at around 1336.20 cm-1 (D-peak) and 1611.87 cm-1 (G-peak), by utilizing ID and IG can be determined that there are 43.22% of sp3 contained in deposited film. Energy Dispersive X-Ray analysis indicated that the deposited thin film compose of carbon atoms 82.00 at% and silicon atoms 18.00 at%. The morphology and the thickness of the film was investigated by scanning electron microscope and atomic force microscope, respectively.