Locally Programmable Chemical Vapor Deposition Exploring a Discovered Corona Charged Precursor Flux Enabling Time and Location Adjustable Growth

• Applicants: Professor Dr. Heiko Jacobs; Dr.-Ing. Leslie Schlag, since 11/2024
• Subject Area: Coating and Surface Technology
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 544048794

This research project combines the classical fields of thin film technology and chemical vapor deposition with a newly discovered localized transport mechanism to enable time and location adjustable crystal growth. For this purpose, we guide a charged flux of precursor molecules, typically used in chemical vapor deposition, through electrodynamic lenses to predefined substrate positions. The idea grew out of our research on localized deposition of microscopic and nanoscopic particles. By reducing the particle size, the electrical conductivity of generated nanostructures approached the literature values of bulk materials. But the use of particles necessarily creates porous structures that are not suitable for all applications. Our hypothesis is that the deposition of solid and crystalline materials should be possible by further reducing the particle size to molecular or atomic level. In preliminary experiments, we could show that precursor molecules for chemical vapor deposition can be electrically charged and locally deposited using a corona discharge. This is true for a variety of molecules, which we could demonstrate in a first publication in the renowned journal ACS Nano. Adjusting the deposition parameters even led to the growth of nano and polycrystalline structures. For future research, we propose a structured investigation of the deposition parameters to enable localized and programmable crystal growth using a charged flux of precursor molecules. For stable deposition conditions, a multi-needle corona discharge reactor needs to be established in order to investigate all relevant forces of localization in a targeted and independent manner. In addition to different precursor materials and conventional deposition parameters, such as temperature, concentration and atmosphere, the electrical parameters of the corona discharge, such as polarity, voltage and current, will be varied as well. In doing so, we anticipate not only a change in the local deposition rate but also a change in the chemical composition and crystal phase. Ultimately, the goal is to establish a localized epitaxy process. Since conventional models and descriptions of chemical vapor deposition processes are no longer applicable, the knowledge gained will be incorporated into a modified deposition model for localized and three-dimensional crystal growth. This will help to deposit newly conceived devices that are not possible with conventional microtechnology processes used today.

• DFG Programme: Research Grants
• Ehemaliger Antragsteller: Dr.-Ing. Johannes Reiprich, until 11/2024