In this work, we developed an atomic layer deposition
(ALD) process
for gold metal thin films from chloro(triethylphosphine)gold(I) [AuCl(PEt3)] and 1,4-bis(trimethylgermyl)-1,4-dihydropyrazine [(Me3Ge)2DHP]. High purity gold films were deposited
on different substrate materials at 180 °C for the first time
with thermal reductive ALD. The growth rate is 1.7 Å/cycle after
the film reaches full coverage. The films have a very low resistivity
close to the bulk value, and a minimal amount of impurities could
be detected. The reaction mechanism of the process is studied in situ
with a quartz crystal microbalance and a quadrupole mass spectrometer.