| Non-contact solution printing methods such as thermal or piezoelectric inkjet are attractive due to their compatibility with various materials and substrates. Interests in their applications in electronics and biotechnology, where requirements on resolution can be demanding, have grown rapidly in recent years. This work describes the use of electrohydrodynamic jet printing methods in which ultrafine nozzles and optimized voltage sequences combine to enable direct, sub-micron patterning resolution. Printing of various material inks, including biomaterials (DNA, protein), suspensions of single walled carbon nanotubes/nanoparticles, and solutions of conducting/insulating polymers, demonstrates some of the features of the methods. Simple devices, such as transistors that use aligned arrays of single walled carbon nanotubes, illustrate its potential applications in electronics. Also, DNA aptamer-based biosensors and DNA-programmed nanoparticle assembly that use spotted arrays of DNA present applications in biotechnology. Printing of charged liquids using e-jet, including the experimental and theoretical studies on time-variant charge distributions demonstrate applications for electrostatic doping of single walled carbon nanotube transistors. |
