The process begins with the formation of a Langmuir film on the surface of a liquid, usually water. These films are composed of amphiphilic molecules, which have both hydrophobic and hydrophilic parts. By spreading these molecules on the water surface, they form a monolayer. The surface pressure is then controlled using barriers to compress the monolayer. Once the desired pressure is achieved, a solid substrate is vertically dipped into the solution and slowly withdrawn, transferring the monolayer onto the substrate.
