The evaporation of complex fluids such as colloidal dispersions or polymer solutions is an elegant route to control the patterns of solutes on a solid surface. In most drying drop problems, a liquid drop containing a dispersed material is transformed into a dense or porous deposit of solids that finds potential application in many growing fields related to ink-jet printing, paints, functional coatings, and nanoparticle-based electronic devices. So far, the evaporation of particle-laden dispersion is mostly studied in the sessile configuration (i.e., drop on a horizontal flat substrate) and the commonly observed feature is the formation of a "coffee-ring" deposit in which most of the particles are deposited at the three-phase contact line. The mechanism of formation of such deposit pattern is known to form as a result of an outward capillary flow originating due to the pinning of the droplet and non-uniform evaporative flux along the surface of the drop.
 
Our study mainly focused on drying a colloidal dispersion to control the deposit patterns on the substrate. The combined effect of substrate orientation and wettability, the influence of configuration of drying dispersion such as sphere-on-plate, and the dispersion dried between two parallel plates were explored to control the final morphology of the dried deposit patterns on the substrates.