The chemical spray pyrolysis technique (SPT) has beenone of the major techniques to deposit a wide variety of materials in thin film form. The prime requisite for obtaining good quality thin film is the optimisation of preparative conditions viz. substrate temperature, spray rate, concentration of solution etc. However, in recent years an emphasis has been given to a variety of atomization techniques such as ultrasonic Atomizers This is the most critical parameter as it enables control over the size of the droplets and their distribution over the preheated substrates. The enhancement in deposition efficiency and improvement in quality of the thin films can be achieved with these atomization techniques.
Ultrasonic spray pyrolysis is being used in a wide variety of applications from nanoparticle formation to cyrstalline thin film deposition. Ultrasonic spray pyrolysis has been used in the formation of nanoparticles of silver, lithium manganese oxide, zinc sulfide (ZnS), lead oxide (PbO), zirconium dioxide (ZrO2) and yttria-stabalized zirconia (YSZ) ceramics. Additionally, ultrasonic spray pyrolysis is being used in the formation of transparent conductive oxide layers such as indium tin oxide (ITO), zinc oxide (ZnO), aluminum zinc oxide (AZO), and fluorine oxide all common in the solar industry.
Ultrasonic spray nozzle technology used in spray pyrolysis is a viable money saving alternative to chemical vapor deposition (CVD), vacuum deposition and sputtering without compromises to quality. Main advantages of ultrasonic spray pyrolysis are:
Cost effective method due to high transfer efficiency in thin film formation.
Substrates with complex geometries can be spray coated.
Films deposited by ultrasonic spray pyrolysis are reproducible.
Highly uniform nanoparticle size formation.
Non clogging nozzles and robust design.