Abstract: Non-contact dispenser printing is a novel, high-precision, template-free, and inexpensive film-forming technique. The quality of printed films is mostly determined by the physicochemical characteristics of the ink, which also have a big effect on the performance of microelectronic devices. In this work, high-performance gas-sensitive ink was made with ZnO-SnO₂ composite gas-sensitive materials as functional phases and ethylene glycol and glycerol as solvents, employing PEG400 as dispersion in place of conventional high molecular weight dispersants. ZnO-SnO₂ composite gas-sensitive films were printed on micro-electromechanical system (MEMS) micro-hotplates using non-contact dispenser method. The effects of PEG400 content and solid content on the physical and chemical properties of ink were discussed by measuring the viscosity, and suspension stability of the ink. The microscopic morphology of the film was observed by SEM. The results show that the composite gas-sensitive ink possesses printability and low-temperature sintering film-forming properties when the solid content is 15% (mass fraction, the same here in after) and the PEG400 content is 6%, and the prepared composite gas-sensitive film is uniform in thickness, with a smooth surface, regular edges, and a good response to acetone gas.

Key words: non-contact dispenser printing, composite gas-sensitive ink, ZnO-SnO₂, PEG400, micro-hotplate, gas sensor