Heat Dissipation Properties of Thin-Film Encapsulation by Insertion of a Metal Thin Film for Organic Light-Emitting Diodes

摘要

Thin-film encapsulation (TFE) technology composed of alternating inorganic/organic materials is a popular encapsulation technology for organic lightemittingdiodes (OLEDs), showing excellent heat-transfer properties combinedwith a thick heat sink. TFE by inserting a metal thin film is proposedto improve the heat-transfer property of an OLED without a separate thickheat sink. According to the presence of metal and its thickness and position,the heat dissipation effect of TFE is compared and optimized via finiteelement simulations. An obvious temperature-reduction effect is observed byplacing a metal thin film after each inorganic/organic unit compared withthat found by placing a metal film after an inorganic/organic unit. Here, theTFE technology composed of alternating inorganic/organic/metal materials isdefined as MET-TFE. At a power density of 900KWm~(-2), the highest internaltemperatures of the devices were 70.14 ℃ (with glass encapsulation),72.37 ℃ (with TFE) and 65.63 ℃ (with MET-TFE). Furthermore, the simulatedthermal analysis results show that the reduction rate of device temperaturefor a device with MET-TFE is comparatively faster than those of devices withTFE and glass encapsulation when increasing the convective heat-transfercoefficient. These results suggest that the MET-TFE structure can effectivelyimprove heat dissipation properties.