Simulation of film thickness distribution for organic vapor phase deposition

摘要

The distribution of the flow field coupled with temperature field in the organic vapor phase deposition (OVPD) is achieved by modeling the transport regime in a simplified OVPD system using Fluent. In the simulation, a hydrodynamic boundary layer close to the substrate is formed, across which the organic molecular vapor diffuse and condense on the substrate. A uniform hydrodynamic boundary layer can be achieved with a higher flow rate, a laminar flow and a low pressure reactor, et al. A uniform thin film can be deposited if the gas dynamics and the boundary layer shape are well understood and controlled. The dynamical deposition of organic vapor in front of the substrate is simulated employing mote carlo method. The simulation shows that a well deposited film can be obtained by creating a uniform hydrodynamic boundary layer. The deposition through a mask aperture is simulated and the effect of molecular mean free path (mfp), mask-substrate separation and the aperture geometry on the deposited shape is analyzed. A high pattern resolution can be achieved by increasing the mfp and decreasing the mask-substrate distance. The using efficiency of materials decreases with the aperture aspect ratio t/w.