Organic optoelectronic devices are appealing for low-performance applications on very low cost and flexible substrates, due to their low-temperature processing. However, it still remains a challenge to develop suitable fabrication techniques to pattern organic thin films on low-cost, large-area substrates. The two techniques used commercially are inkjet printing of polymers, which limits the morphology and performance of devices, and shadow-masking of vacuum sublimation for small molecule materials, which is not scalable to large-area substrates. In this thesis, we investigate the use of MicroElectroMechanical Systems (MEMS) to provide new ways of patterning organic materials deposited by an evaporative process. We present the design, fabrication, modeling and characterization of two generations of micromachined printheads developed to expand the possibilities of printing of organic optoelectronics. The design and fabrication of a compact electrostatic actuator enabling the first generation of printhead is first presented. It is then used to actuate a microshutter, and modulate the flux of evaporated organic materials in a vacuum chamber. We prove the feasibility of evaporative printing of small molecular organic materials at resolutions of the order of 800 dpi with high-throughput on large areas.
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