US 12,278,313 B2
Light-emitting device with internal non-specular light redirection and anti-reflective exit surface
Antonio Lopez-Julia, Aachen (DE); Venkata Ananth Tamma, San Jose, CA (US); Aimi Abass, Aachen (DE); and Philipp-Immanuel Schneider, Berlin (DE)
Assigned to Lumileds LLC, San Jose, CA (US)
Filed by LUMILEDS LLC, San Jose, CA (US)
Filed on Mar. 30, 2023, as Appl. No. 18/128,556.
Application 18/128,556 is a continuation of application No. 17/121,014, filed on Dec. 14, 2020, granted, now 11,641,007.
Claims priority of provisional application 62/948,704, filed on Dec. 16, 2019.
Claims priority of application No. 20160667 (EP), filed on Mar. 3, 2020.
Prior Publication US 2023/0290906 A1, Sep. 14, 2023
Int. Cl. H01L 33/44 (2010.01); H01L 33/00 (2010.01); H01L 33/58 (2010.01)
CPC H01L 33/44 (2013.01) [H01L 33/005 (2013.01); H01L 33/58 (2013.01); H01L 2933/0025 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A semiconductor light-emitting device comprising:
a semiconductor light-emitting diode structure having front and back surfaces and one or more light-emitting active layers arranged to emit output light at a nominal vacuum wavelength λ0 to propagate within the semiconductor diode structure, the front surface being characterized by a critical angle Θc at the nominal vacuum wavelength λ0;
an anti-reflection coating on the front surface that is arranged so that the front surface exhibits reflectivity, for a range of internal incidence angles on the front surface less than Θc and at the nominal vacuum wavelength λ0, that is less than corresponding Fresnel reflectivity of the front surface without the anti-reflection coating; and
a redirection layer on the back surface that includes an array of nano-antennae that include one or more antenna materials, are shaped, sized, and spaced relative to the nominal vacuum wavelength λ0, and arranged along the redirection layer, so as to reradiate, upon irradiation by the output light at internal incidence angles on the back surface greater than Θc and at the nominal vacuum wavelength λ0, at least a portion of the output light to result collectively in redirection thereof to propagate toward the front surface within the range of internal incidence angles on the front surface less than Θc,
the semiconductor light-emitting device exhibiting a mean number of redirections per photon emitted by the active layer, by the redirection layer before exiting through the front surface, that is less than 30.