LCVD of aluminium stripes obtained by pyrolysis of TMAA and TMA

Abstract

Maskless patterning of aluminium has been achieved by using visible light from a copper bromide vapor laser for pyrolytic decomposition of trimethylaluminium (TMA) and trimethylamine alane (TMAA). A silicon monocrystalline wafer was used as a substrate. The deposition was carried out at different process parameters (partial pressure of the precursors, laser power and scanning speed). The analysis of the resultant stripes included scanning electron microscopy, Auger electron spectroscopy, Talystep and electrical resistance measurements. The crystalline structure of the layers showed well-defined grains for both precursors. The Auger electron spectra indicated pure aluminium layers with small quantities of oxygen and carbon for stripes deposited from TMAA while those obtained from TMA were more contaminated. The difference in the layers composition for the used precursors resulted in their resistivity values. The low resistivities of aluminium stripes deposited from TMAA (up to 4.0 μΩ.cm) makes it promising precursor for metalization with aluminium and especially for chemical vapor deposition enhanced with pulsed visible laser