US 11,894,488 B2
LED chips with irregular microtextured light extraction surfaces, and fabrication methods
Peter Scott Andrews, Durham, NC (US)
Assigned to CreeLED, Inc., Durham, NC (US)
Filed by CreeLED, Inc., Durham, NC (US)
Filed on Jun. 24, 2021, as Appl. No. 17/357,091.
Claims priority of provisional application 63/044,746, filed on Jun. 26, 2020.
Prior Publication US 2021/0408328 A1, Dec. 30, 2021
Int. Cl. H01L 33/20 (2010.01); H01L 33/32 (2010.01); H01L 33/50 (2010.01); H01L 33/38 (2010.01); H01L 33/00 (2010.01)
CPC H01L 33/20 (2013.01) [H01L 33/005 (2013.01); H01L 33/32 (2013.01); H01L 33/382 (2013.01); H01L 33/50 (2013.01); H01L 2933/0016 (2013.01); H01L 2933/0041 (2013.01)] 22 Claims
OG exemplary drawing
 
1. A LED chip comprising:
an active layer comprising a plurality of active layer portions configured to produce electrically activated emissions, with a plurality of streets defined through the active layer and arranged to segregate individual active layer portions of the plurality of active layer portions;
a substrate comprising a plurality of substrate portions supporting the plurality of active layer portions, wherein the substrate comprises a light-transmissive substrate material and each substrate portion comprises a light extraction surface; and
a plurality of anode-cathode pairs associated with the plurality of active layer portions;
wherein active layer portion of the plurality of active layer portions comprises a different anode-cathode pair of the plurality of anode-cathode pairs and is configured to illuminate a different substrate portion of the plurality of substrate portions and transmit light through the light extraction surface of the substrate portion, such that the plurality of active layer portions and the plurality of substrate portions form a plurality of pixels;
wherein each light extraction surface comprises a microtextured etched surface having a non-repeating, irregular textural pattern.