Monolithic multijunction power converter

Abstract

Resonant cavity power converters for converting radiation in the wavelength range from 1 micron to 1.55 micron are disclosed. The resonant cavity power converters can be formed from one or more lattice matched GaInNAsSb junctions and can include distributed Bragg reflectors and/or mirrored surfaces for increasing the power conversion efficiency.

1 - 11 . (canceled) 
     
     
         12 . A multijunction power converter, comprising:
 two or more GaInNAsSb junctions, wherein each of the two or more GaInNAsSb junctions is lattice matched to GaAs or to Ge and has a bandgap configured to absorb at a monochromatic wavelength, wherein the monochromatic wavelength is within a range from 1.3 microns to 1.55 microns;   a tunnel junction separating each of the two or more GaInNAsSb junctions;   a first semiconductor layer overlying the two or more GaInNAsSb junctions, wherein the first semiconductor layer does not absorb at the monochromatic wavelength and is lattice matched to GaAs or to Ge and to each of the two or more GaInNAsSb junctions; and   a second semiconductor layer underlying the two or more GaInNAsSb junctions, wherein the second semiconductor layer does not absorb at the monochromatic wavelength and is lattice matched to GaAs or to Ge and to each of the two or more GaInNAsSb junctions;   wherein when irradiated with radiation at the monochromatic wavelength, the multijunction power converter is characterized by a constant power conversion efficiency of at least 18% for an input power within a range from 0.6 W to 6 W.   
     
     
         13 . The multijunction power converter of  claim 12 , wherein the multijunction power converter is characterized by a power conversion efficiency of at least 20% for an input power within a range from 0.6 W to 6 W. 
     
     
         14 . The multijunction power converter of  claim 12 , wherein the multijunction power converter is characterized by a conversion efficiency within a range from 18% to 25% for an input power within a range from 0.6 W to 6 W. 
     
     
         15 . The multijunction power converter of  claim 12 , wherein each of the two or more GaInNAsSb Junctions independently has a thickness within a range from 100 nm to 1 micron. 
     
     
         16 . The multijunction power converter of  claim 12 , wherein each of the two or more GaInNAsSb junctions has a bandgap that is matched to an energy of the monochromatic wavelength. 
     
     
         17 . The multijunction power converter of  claim 12 , wherein each of the first semiconductor layer and the second semiconductor layer comprises GaAs. 
     
     
         18 . The multijunction power converter of  claim 12 , comprising a substrate underlying the second semiconductor layer, wherein the substrate comprises GaAs. 
     
     
         19 . The multijunction power converter of  claim 12 , comprising a substrate underlying the second semiconductor layer, wherein the substrate comprises Ge. 
     
     
         20 . The multijunction power converter of  claim 12 , comprising a back mirror underlying the second semiconductor layer. 
     
     
         21 . The multijunction power converter of  claim 12 , comprising an antireflection coating overlying the first semiconductor layer. 
     
     
         22 . The multijunction power converter of  claim 12 , wherein, the monochromatic wavelength is 1.32 microns. 
     
     
         23 . The multijunction power converter of  claim 12 , comprising:
 a first electrical contact to the first semiconductor layer; and   a second electrical contact to the second semiconductor layer.   
     
     
         24 . A multijunction power converter device, comprising a plurality of the multijunction power converters of  claim 12  configured in a Pi structure in which the plurality of multijunction power converters are disposed in concentric rings around a central axis, wherein each of the multiple multijunction power converters is separated by an insulator and is connected in series. 
     
     
         25 . A multijunction power converter device, comprising a plurality of the multijunction power converters of  claim 12  interconnected in series.