SEMINAIRE LMGP - 25.02.2020 - Nils BOYSEN

Abstract
The fabrication of functional thin films for various applications by metal-organic chemical vapor deposition (MOCVD) or atomic layer deposition (ALD) plays a crucial role in the micro- and optoelectronic industry. One of the most important factors during the deposition of functional thin films with the beforementioned techniques is the behavior of the chemical precursor during evaporation, transport and interaction with the substrate. The thermal properties, reactivity and stability of the precursor dictates not only whether it can be used in MOCVD and ALD, but also the functional properties of the resulting thin films that are forms an important figure of merit for their application in micro- and optoelectronic devices. Exemplarily, for the deposition of metallic silver by ALD, only one commercially precursor [Ag(fod)(PEt3)] is available and shows unwanted issues during thin film growth such as halogen, oxygen and phosphine incorporation and the release of toxic and corrosive byproducts. The newly developed precursor [Ag(NHC)(hmds)] overcomes these issues and additionally decreases the percolation threshold of the metal islands to form conductive silver thin films at a lower ALD cycle count when compared to [Ag(fod)(PEt3)] in a spatial ALD setup. This example highlights the importance of the rational precursor design for CVD and ALD applications to enhance the performance of the MOCVD and ALD processes, while this seminar should give an overview about the opportunities and challenges for rational precursor design.