US 11,929,385 B2
Method for forming a pixelated optoelectronic device on a substrate
Yunlong Li, Heverlee (BE); Stefano Guerrieri, Kessel-lo (BE); Ming Mao, Leuven (BE); and Luis Moreno Hagelsieb, Brussels (BE)
Assigned to Imec vzw, Leuven (BE)
Filed by IMEC VZW, Leuven (BE)
Filed on Jul. 2, 2021, as Appl. No. 17/366,843.
Claims priority of application No. 20184095 (EP), filed on Jul. 3, 2020.
Prior Publication US 2022/0005862 A1, Jan. 6, 2022
Int. Cl. H01L 27/146 (2006.01)
CPC H01L 27/14689 (2013.01) [H01L 27/14621 (2013.01); H01L 27/14627 (2013.01); H01L 27/14643 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method for forming a pixelated optoelectronic stack on a substrate, the method comprising:
forming a stacked layer structure on a substrate, the stacked layer structure comprising:
a bottom electrode layer;
an optoelectronic layer over the bottom electrode layer; and
a patterned hard-mask over the optoelectronic layer, wherein a pattern of the patterned hard-mask comprises at least two hard-mask islands separated by a hard-mask-free area;
replicating the pattern into the optoelectronic layer and the bottom electrode layer by etching through the optoelectronic layer and the bottom electrode layer selectively with respect to the hard-mask, thereby forming a first intermediate pixelated stack on top of the substrate, the first intermediate pixelated stack comprising at least two islands of stack separated from one another by stack-free areas;
forming an electrically insulating layer on the first intermediate pixelated stack to fill the stack-free areas and cover the at least two islands of stack;
removing a top portion of the electrically insulating layer and removing any remaining hard-mask so that a top surface of the electrically insulating layer is coplanar with an exposed top surface of the first intermediate pixelated stack, yielding a second intermediate pixelated stack on top of the substrate; and
forming a top transparent electrode layer over the second intermediate pixelated stack.