BACKGROUND

Light emitting diodes (LEDs), which include light emitting elements (LEEs), are commonly used as light sources in various applications. LEDs can be more energy-efficient than traditional light sources, providing much higher energy conversion efficiency than incandescent lamps and fluorescent light, for example.

To manufacture an LED, adhesive layers are often used between different components of the LED. To optimize the operation of an LED, one or more of the adhesive layers should conform by having certain properties. These properties can include, but are not limited to, temperature requirements, coloring requirements, adhesion, and the like.

SUMMARY

According to aspects of the disclosure, devices are disclosed herein which include a first LED device layer, a second LED device layer, and an adhesive bondline disposed between the first LED device layer and the second LED device layer. The adhesive bondline includes a bondline thickness, a plurality of spacers disposed within the adhesive bondline, and a silicone matrix. The plurality of spacers may have a diameter or a shortest axis as low as 0.5 micrometers to as high 10 micrometers, and preferably as high as 5 micrometers, with each spacer sample having a coefficient of variation (CV) preferably no larger than 10% and preferably no larger than 5%. The plurality of spacers may include silica, alumina, crosslinked polystyrene-co-divinylbenze (PS-co-DVB) and may be inorganic or organic.

According to aspects of the disclosure, a method is disclosed herein which includes depositing or obtaining a first LED device layer, depositing an adhesive bondline between the first LED device layer and a second LED device layer. The adhesive bondline may have a bondline thickness and may include a plurality of spacers disposed within the adhesive bondline, and a silicone matrix. The plurality of spacers may have a diameter or a shortest axis between 0.5 and 10 micrometers, and preferably between 1 and 5 micrometers, and the coefficient of variability (CV) not larger than 10%, and preferably not larger than 5%, for each sample of spacers the mean diameter or shortest axis. The plurality of spacers may be include silica, alumina, soda lime glass, PS-co-DVB, and may be inorganic or polymeric.

