A method to fabricate a flexible array of micro III-nitride devices, including but not limited to LEDs, detectors, and vertical-cavity surface-emitting lasers (VCSELs).
Today’s commercially available III-nitride LEDs are made of thin films that are grown epitaxially on the c-plane on sapphire substrates. However, these films have high threading dislocation (TD) densities, which hinder the material quality and optical performance. To combat this problem, efforts have been made to grow thin films on bulk GaN substrates. These bulk substrates include various orientations, including the basal c-plane, nonpolar a-plane, m-plane families, and semipolar plane families. With the appropriate technique, micro III-nitride devices grown on bulk GaN substrates could lead to flexible arrays of these devices with broad applications.
Researchers at UC Santa Barbara have created a method to fabricate a flexible array of micro III-nitride devices, including but not limited to LEDs, detectors, and vertical-cavity surface-emitting lasers (VCSELs). The method combines the epitaxy of III-nitride thin films, the flip-chip bonding of these thin films to a flexible submount, and the use of a photoelectrochemical (PEC) etch technique to separate the devices from the rigid substrate. The flip-chip bonding process involves wafer bonding the light emitting device structure and substrate so that the microLED films are in-between the host substrate and submount. The PEC etch technique allows the bulk GaN substrates to be reused in the fabrication process.
· Flexible array of inorganic light-emitting devices
· Substrates can be recycled
· Reusing bulk GaN substrates is cost-effective
· Solid state lighting systems for flexible displays and wearable electronics
|United States Of America||Published Application||20170236807||08/17/2017||2015-205|
indssl, indled, microLED, wearables, III-nitride, indfeat, indmicroelec