Atomic Layer Deposition of High-Purity Palladium Films from Pd(hfac)(2) and H-2 and O-2 Plasmas

作者：Weber Matthieu J; Mackus Adriaan J M; Verheijen Marcel A; Longo Valentino; Bol Ageeth A; Kessels Wilhelmus M M^*

来源：Journal of Physical Chemistry C, 2014, 118(16): 8702-8711.

DOI：10.1021/jp5009412

A plasma-assisted atomic layer deposition (ALD) process has been developed that allows for low temperature (100 degrees C) synthesis of virtually 100% pure palladium thin films with low resistivity of 24 +/- 3 mu Omega cm on oxide substrates. This process is based on Pd(hfac)(2) (hfac = hexafluoroacetylacetonate) precursor dosing followed by sequential H-2 plasma and O-2 plasma steps in a so-called ABC-type ALD process. Gas-phase infrared spectroscopy studies revealed that the O-2 plasma pulse is required to remove carbon contaminants from the Pd surface that remain after the H-2 plasma reduction step. Omitting the O-2 plasma step, that is, Pd ALD from Pd(hfac)(2) and H-2 plasma in a typical AB-like ALD process, leads to a carbon contamination of %26gt;10% and significantly higher resistivity values. From transmission electron microscopy, it has also been observed that the ABC-type process leads to a faster nucleation of the Pd nanoparticles formed during the initial stage of film growth. As this novel process allows for the deposition of high-purity Pd at low temperatures, it opens prospects for various applications of Pd thin films and nanoparticles.

• 出版日期2014-4-24