US 12,278,224 B2
Method for producing nitride mesas each intended to form an electronic or optoelectronic device
Guy Feuillet, Grenoble (FR); Blandine Alloing, Valbonne (FR); Hubert Bono, Grenoble (FR); Roy Dagher, Grenoble (FR); Jesus Zuniga Perez, Biot (FR); Matthew Charles, Grenoble (FR); Julien Buckley, Grenoble (FR); and Rene Escoffier, Grenoble (FR)
Assigned to COMMISSARIAT A L'ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES, Paris (FR); and CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE, Paris (FR)
Appl. No. 17/620,484
Filed by COMMISSARIAT A L'ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES, Paris (FR); and CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE, Paris (FR)
PCT Filed Jun. 22, 2020, PCT No. PCT/EP2020/067382
§ 371(c)(1), (2) Date Dec. 17, 2021,
PCT Pub. No. WO2020/254695, PCT Pub. Date Dec. 24, 2020.
Claims priority of application No. 19 06756 (FR), filed on Jun. 21, 2019.
Prior Publication US 2022/0359479 A1, Nov. 10, 2022
Int. Cl. H01L 25/16 (2023.01); H01L 21/02 (2006.01); H01L 21/786 (2006.01); H01L 25/07 (2006.01); H01L 29/66 (2006.01); H01L 33/00 (2010.01); H01L 23/00 (2006.01); H01L 29/778 (2006.01)
CPC H01L 25/167 (2013.01) [H01L 21/0265 (2013.01); H01L 21/786 (2013.01); H01L 25/072 (2013.01); H01L 29/66462 (2013.01); H01L 33/0093 (2020.05); H01L 24/29 (2013.01); H01L 24/32 (2013.01); H01L 24/83 (2013.01); H01L 29/7786 (2013.01); H01L 33/007 (2013.01); H01L 2224/29124 (2013.01); H01L 2224/29166 (2013.01); H01L 2224/29184 (2013.01); H01L 2224/29186 (2013.01); H01L 2224/32145 (2013.01); H01L 2224/83203 (2013.01)] 24 Claims
OG exemplary drawing
 
1. A method for obtaining a plurality of mesas, each mesa being made at least in part of a nitride (N), wherein the method comprises the following successive steps of:
providing a stack comprising a substrate and at least the following layers disposed in succession from the substrate:
a flow layer, made of a material with a glass transition temperature, the flow layer having a glass transition temperature Tglass transition, and
a crystalline layer, which is different from the flow layer,
forming pads by etching through the crystalline layer but only through a portion of the flow layer such that:
a bottom portion of the flow layer is retained between the pads,
each pad includes at least a flow section, formed by at least one portion of the flow layer and being directly connected to the bottom portion of the flow layer between the pads, and a crystalline section, formed by the crystalline layer and overlying the flow section, and
the pads are distributed over the substrate so as to form a plurality of sets of pads,
epitaxially growing a crystallite on at least some of said pads and continuing the epitaxial growth of the crystallites until the crystallites carried by the adjacent pads of a same set coalesce, so as to form a nitride mesa on each set, the epitaxial growth being performed at a temperature Tepitaxy, such that:
Tepitaxy≥k1×Tglass transition, where k1≥0.8, and
interrupting the epitaxial growth of the crystallites before crystallites belonging to two separate sets start to coalesce, so that the formed mesas are spaced apart from one another,
wherein, after the epitaxial growth and formation of the mesas, an adjacent pair of pads has a space formed therebetween and a side surface of the flow section of each pad of the pair of pads forms part of a side surface of the space.