Spectral conversion of InGaN ultraviolet microarray light-emitting diodes using fluorene-based red-, green-, blue-, and white-light-emitting polymer overlayer films

We report the fabrication of hybrid organic/inorganic semiconductor light-emitting devices that operate across the entire visible spectrum. The devices are based on a series of blue-, green-, and red-light-emitting polyfluorene materials that convert the emission from an array of micron-sized ultraviolet InGaN light-emitting diodes. We also demonstrate white-light-emitting versions of these hybrid devices by employing single films of carefully adjusted polyfluorene blends in which cascade energy transfer occurs between the constituent materials. The spectral and operating characteristics of the devices are described in detail. Such organic emission layer/inorganic light-emitting diode (LED) array based devices may provide a promising route to the fabrication of low-cost full-color microdisplays and other instrumentation devices.