Conference Program - LOPE-C 2011

SCIENTIFIC CONF. | WEDNESDAY-JUNE 29, 2011
Track 5
Laser Processing (02:30 pm - 04:00 pm) | LOCATION HARMONIE E / LEVEL C2
03:40 pm Debris-free maskless selective laser patterning of PEDOT: PSS for organic electronics applications
Dr Dimitris Karnakis,
Oxford Lasers Ltd, United Kingdom
Rapid developments in large-area organic electronics promise thin, lightweight low cost devices for several key applications (OLED, OTFT, OPV, etc) on glass or flexible
substrates. When directly patterned deposition is not feasible, requiring instead full-area coating and post-patterning techniques, laser processing is gradually emerging as
a key enabling tool. However, very few reports discuss laser thin-film patterning, especially on flexible substrates. The aim here is to examine the potential of ultrafast
DPSS lasers for such applications and demonstrate a stable process window for large area selective layer patterning. More specifically, we will present detailed ablation
studies on the removal of transparent conductive oxides on barrier layers or polyester substrates, metal electrodes on organic layers and conductive polymers
(PEDOT:PSS) on barrier layers or metal grids. The highly deterministic character of the process will be discussed revealing damage thresholds, indicative process quality
and process speed limitations. Careful examination with optical profilometry, SEM and high-speed imaging techniques reveals the importance of laser wavelength and
critically laser pulse duration. A stress-assisted ablation mechanism is believed to be driving this process, which when carefully optised, can result in debris-free, low
temperature patterning with demonstrably [1] no detrimental effects to the device performance.
04:00 pm COFFEE BREAK
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