Diseño y construcción de un sistema automatizado para la elaboración de películas delgadas, por el método de inmersión

The process of coating by immersion, or Dip-Coating, is utilized to obtain thin mono-coats and multi-coats. It involves the immersion and later withdrawal of a substrate (glass, metal, etc.) into a reservoir containing a solution used for the formation of a coat. In this paper we describe a low cost microcontroller-based dip-coater design and construction. The coater has a withdrawal velocity ranging between 0.8 cm/min and 25 cm/min. To achieve this performance, a mechanical subsystem for the substrate transportation and an electronic and computational subsystem for its control, was designed and elaborated using the microcontroller PIC16F877A. The system is operated by means of a notebook or a PDA. To test the complete system, a series of silica over glass films with one, five and ten coats were made. They were characterized by means of the transmission electron microscopy technique (TEM) and optical interferometry technique.