Polymer pixel enhancement by laser-induced forward transfer for sensor applications

Abstract

This paper presents polymer pixel printing for applications in chemoselective sensors where nanosecond laser direct transfer methods, with a triazene polymer (TP) acting as a Dynamic Release Layer (DRL), are used. A sys- tematic study of laser fluence, donor film morphology and both single- and multiple-pixel deposition were optimized with the final goal to obtain continuous pixels of sensi- tive polymers, polyethylenimine (PEI) and polyisobutylene (PIB), on SAW surfaces. Morphology characterization after the laser transfer has been performed by Optical Microscopy and Scanning Electron Microscopy (SEM). The responses of the coated transducers were measured after deposition with different laser fluences and it was found that a fluence under 625 mJ/cm 2 was required in order to prevent damage of the interdigital transducers (IDT) of the sensor devices. The sen- sitivity of the polymer coated devices to acetone concentra- tions gives an indication that LIFT can be used for printing sensitive polymer pixels onto transducer devices.