IoT-Based Spin-Coater for Thin Films Fabrication

This paper outlines the development of a low-cost Internet of Things (IoT)-based spin-coater for thin film deposition. Compared to existing commercial microcontroller-based spin-coaters, the standout feature of this spin-coater is its ability to connect with the user for system control and data input via hotspot/Wi-Fi/Bluetooth and to store data for future use. This spin-coater can be operated remotely inside a glovebox for device fabrication, providing superior monitoring of the spin-coating process through smartphones or web browsers. ZnO thin films have been deposited on a glass substrate using IoT-based and commercial spin-coaters. The structural, optical, and surface morphological properties of the ZnO films can be compared for both Systems. The experimental data shows comparable transmittance and absorbance, a 3.19 eV bandgap energy, and a 23.99 nm larger crystallite structure compared to a 3.18 eV bandgap energy of 21.68 nm in the commercial spincoater. The SEM images reveal a nanofiber structure. The system is simple, lightweight, and cost-effective, eliminating the need for a vacuum pump as required by commercial systems.