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Conference on Laser Applications in Microelectronic and Optoelectronic Manufacturing (LAMOM) XVIII, San Francisco, CA, FEB 04-07, 2013International audienceThe development of organic electronic requires a non contact digital printing process. The European funded e-LIFT project investigated the possibility of using the Laser Induced Forward Transfer (LIFT) technique to address this field of applications. This process has been optimized for the deposition of functional organic and inorganic materials in liquid and solid phase, and a set of polymer dynamic release layer (DRL) has been developed to allow a safe transfer of a large range of thin films. Then, some specific applications related to the development of heterogeneous integration in organic electronics have been addressed. We demonstrated the ability of LIFT process to print thin film of organic semiconductor and to realize Organic Thin Film Transistors (OTFT) with mobilities as high as 4 10(-2) cm(2).V-1.s(-1) and I-on/I-off ratio of 2.8 10(5). Polymer Light Emitting Diodes (PLED) have been laser printed by transferring in a single step process a stack of thin films, leading to the fabrication of red, blue green PLEDs with luminance ranging from 145 cd.m(-2) to 540 cd.m(-2). Then, chemical sensors and biosensors have been fabricated by printing polymers and proteins on Surface Acoustic Wave (SAW) devices. The ability of LIFT to transfer several sensing elements on a same device with high resolution allows improving the selectivity of these sensors and biosensors. Gas sensors based on the deposition of semiconducting oxide (SnO2) and biosensors for the detection of herbicides relying on the printing of proteins have also been realized and their performances overcome those of commercial devices. At last, we successfully laser-printed thermoelectric materials and realized microgenerators for energy harvesting applications

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Organic light-emitting devices (OLEDs) are studied, containing polyvinylcarbazole and bathocuproine layers, with or without insertion of a polymethylmethacrylate layer at the organic interface. The latter efficiently blocks electrons but not holes. Large currents flowing in the diodes are limited by the interplay of transmission of holes through the organic heterojunction and space charge limitation in the anodic part of the diode. Minority electron currents are always small. An illustrative analytical model is presented, showing the evolution of fields in the anodic and cathodic compartments and the possibility of two physically acceptable solutions. Electroluminescence is observed only in the diodes without polymethylmethacrylate above a threshold V ∼ 7 V. Quantum yields of both phosphorescence and fluorescence and the triplet lifetime of BCP have also been determined.