Definition of criteria and design parameters of aerosol-assisted chemical vapor deposition system (AACVD)

Abstract

The aerosol-assisted chemical vapor deposition technique (AACVD) consists of a process of atomization of a precursor solution, which generates droplets that travel through a carrier gas to the surface of a substrate, a thin film grows on it depending on variables such as the rate of deposit, temperature of the substrate, drop size and number of layers. In this paper, we present the mechanical, electrical and electronic design criteria taken into account for the implementation of the technique. The prototype is a metal structure that supports a heating plate and a substrate holder where the sample to be coated is located; the plate is controlled with a power microcontroller to keep the substrate temperature constant during the deposit. In addition, a spray system with a 241TM ultrasonic nebulizer and an air heating system was implemented by means of a furnace in function of the MC5438 ramp. The steam injection nozzle is guided by a NEMA 17 controlled motor by Arduino and travels along the substrate allowing the variation of: the deposit speed, number of layers, delay time between layers and distance to travel. Transmittance spectra of thin films of titanium oxide deposited with different deposition parameters are compared. In conclusion, based on the defined design criteria and parameters, the AACVD technique was built and implemented, which has allowed the deposite of homogeneous coatings with different applications depending on the precursor salts and the deposit parameters.