Electrospray deposition of functional film, an Experimental Parametric Study

Abstract

Due to wide printing applications in microelectronic devices as well as for drug discovery purpose in pharmaceutical industries and development of DNA microarrays in biotechnology, patterning is a fundamental need of many printing operations specially in micro or nano scale range. There are several printing techniques like Piezoelectric inkjet printing system and thermal inkjet printing system which are time taken and very costly. The loss of costly material which is used in these techniques are very high. To overcome this problem, electrospray inkjet printing technique introduced in which printing at high resolution and low cost. In this study, silver nanowires were synthesized through polyol method. NaCl has been as ink precursor. PVP has been used as protective and reducing agent. FTIR results confirm that Ethylene glycol and PVP removed in silver nanowires. UV visible spectroscopy, XRD and SEM conforms the presence of silver nanowires. Parametric study of electrospray was done. Analyzed effect of droplet diameter, effect of nozzle, effect of flowrate, effect of nozzle to substrate distance and effect of substrates by applied voltage. Dry spray was come at low flowrate, medium distance and minimum nozzle ID. Electrospray was used for the deposition of PEDOT:PSS film as well as to deposit silver nanowires (AgNWs) embedded PEDOT:PSS nanocomposite thin films on a glass substrate. Surface morphology of deposited films were analyzed by SEM, and conductivity of deposited film was analyzed by IV measurement. Conductivity of PEDOT:PSS was improved by making composite of AgNO3/PEDOT:PSS.