US 11,655,558 B2
Methods for improved III/V nano-ridge fabrication on silicon
Bernardette Kunert, Wilsele (BE); Robert Langer, Heverlee (BE); Yves Mols, Wijnegem (BE); and Marina Baryshnikova, Leuven (BE)
Assigned to Imec VZW, Leuven (BE)
Filed by IMEC VZW, Leuven (BE)
Filed on Aug. 18, 2020, as Appl. No. 16/996,146.
Claims priority of application No. 19195256 (EP), filed on Sep. 3, 2019.
Prior Publication US 2021/0062360 A1, Mar. 4, 2021
Int. Cl. C30B 25/04 (2006.01); C30B 25/10 (2006.01); C30B 25/18 (2006.01); C30B 29/42 (2006.01); C30B 29/60 (2006.01); H01L 21/762 (2006.01); H01L 21/768 (2006.01)
CPC C30B 25/04 (2013.01) [C30B 25/105 (2013.01); C30B 25/18 (2013.01); C30B 29/42 (2013.01); C30B 29/60 (2013.01); H01L 21/76224 (2013.01); H01L 21/76877 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method for growing at least one III/V nano-ridge on a silicon substrate in an epitaxial growth chamber, wherein the nano-ridge has a length along a longitudinal axis of the nano-ridge that is greater than each of a width and a height of the nano-ridge perpendicular to the longitudinal axis of the nano-ridge, the method comprising:
patterning an area on a silicon substrate thereby forming a trench on the silicon substrate; and
growing the at least one III/V nano-ridge, wherein growing the at least one III/V nano-ridge comprises:
initiating growth of the at least one III/V nano-ridge in the trench, thereby forming a filling layer of the at least one III/V nano-ridge inside the trench; and
continuing growth of the at least one III/V nano-ridge out of the trench on top of the filling layer by providing at least one group III precursor and at least one group V precursor in the epitaxial growth chamber, thereby forming a top part of the at least one III/V nano-ridge, wherein at least one surfactant is added in the chamber in addition to the at least one group III precursor and the at least one group V precursor when the III/V nano-ridge is growing out of the trench, thereby changing the growth characteristics of the III/V nano-ridge such that the III/V nano-ridge forms a flat (001) top surface, and wherein the at least one surfactant is added in the chamber subsequent to the trapping of all misfit induced defects in the III/V nano-ridge at the side walls of the trench such that the at least one surfactant is not added in the chamber when initiating growth of the at least one III/V nano-ridge in the trench or when forming a filling layer of the at least one III/V nano-ridge inside the trench.