Reductive Thermal Atomic Layer Deposition Process for Gold

Anton Vihervaara; Timo Hatanpää; Heta-Elisa Nieminen; Kenichiro Mizohata; Mykhailo Chundak; Mikko Ritala

doi:10.1021/acsmaterialsau.2c00075

Reductive Thermal Atomic Layer Deposition Process for Gold

ACS Mater Au. 2023 Jan 11;3(3):206-214. doi: 10.1021/acsmaterialsau.2c00075. eCollection 2023 May 10.

Authors

Anton Vihervaara¹, Timo Hatanpää¹, Heta-Elisa Nieminen¹, Kenichiro Mizohata², Mykhailo Chundak¹, Mikko Ritala¹

Affiliations

¹ Department of Chemistry, University of Helsinki, P.O. Box 55, HelsinkiFI-00014, Finland.
² Department of Physics, University of Helsinki, P.O. Box 43, HelsinkiFI-00014, Finland.

Abstract

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.