US 11,670,540 B2
Substrates including useful layers
Didier Landru, Le Champ-près-Froges (FR); Nadia Ben Mohamed, Echirolles (FR); Oleg Kononchuk, Theys (FR); Frédéric Mazen, Saint Egreve (FR); Damien Massy, Grenoble (FR); Shay Reboh, Grenoble (FR); and François Rieutord, Saint Egreve (FR)
Assigned to Soitec, Bernin (FR); and Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Paris (FR)
Filed by Soitec, Bernin (FR); and COMMISSARIAT À L'ÉNERGIE ATOMIQUE ET AUX ÉNERGIES ALTERNATIVES, Paris (FR)
Filed on Mar. 2, 2021, as Appl. No. 17/190,004.
Application 17/190,004 is a continuation of application No. 16/324,461, granted, now 10,950,491, issued on Mar. 16, 2021, previously published as PCT/FR2017/052161, filed on Aug. 1, 2017.
Claims priority of application No. 1657722 (FR), filed on Aug. 11, 2016.
Prior Publication US 2021/0202302 A1, Jul. 1, 2021
Int. Cl. H01L 21/762 (2006.01); H01L 21/324 (2006.01); H01L 21/263 (2006.01)
CPC H01L 21/76254 (2013.01) [H01L 21/263 (2013.01); H01L 21/324 (2013.01); H01L 21/76251 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A substrate, comprising:
a useful layer affixed to a support substrate;
wherein a surface of the useful layer located on a side of the useful layer opposite the support substrate comprises:
a first region comprising a first surface roughness, the first region located proximate to a geometric center of the surface, the first region occupying a majority of an area the surface; and
a second region comprising a second, higher surface roughness, the second region located proximate to a periphery of the surface, the second region occupying a minority of the area of the surface;
wherein the first region is at least substantially free of periodical patterns in variations of surface height, and the second region comprises periodical patterns in variations in surface height.