A method of fabricating a multijunction photovoltaic cell, comprising: forming a first bonding layer at least substantially comprised of a first III-V material on a major surface of a first element comprising a first tandem solar cell , wherein the first III-V material comprises an indium phosphide material; forming a second bonding layer at least substantially comprised of a second III-V material on a major surface of a second element comprising a second tandem solar cell , wherein the second III-V material comprises at least one of a gallium arsenide material and a gallium indium phosphide material; doping the first bonding layer and the second bonding layer with an n-type dopant at a doping concentration of at least 1.5 x 10 19 cm- 3 , and selecting the n-type dopant to comprise at least one of selenium and tellurium; disposing the first bonding layer and the second bonding layer between the first element and the second element ; and attaching the first element and the second element to one another at a bonding interface disposed between the first bonding layer and the second bonding layer ; wherein doping the first bonding layer and the second bonding layer with an n-type dopant reduces a wavelength of an absorption edge of the first bonding layer and the second bonding layer by at least two hundred nanometers as compared to the undoped first bonding layer and second bonding layer ; wherein forming each of the first bonding layer and the second bonding further comprises epitaxially growing the first bonding layer and the second bonding layer ; and wherein epitaxially growing the first bonding layer and the second bonding further comprises, epitaxially growing at least one bonding surface having a surface root mean square, rms, roughness of less than 0.5 nm as-grown. forming a first bonding layer at least substantially comprised of a first III-V material on a major surface of a first element comprising a first tandem solar cell , wherein the first III-V material comprises an indium phosphide material; forming a second bonding layer at least substantially comprised of a second III-V material on a major surface of a second element comprising a second tandem solar cell , wherein the second III-V material comprises at least one of a gallium arsenide material and a gallium indium phosphide material; doping the first bonding layer and the second bonding layer with an n-type dopant at a doping concentration of at least 1.5 x 10 19 cm- 3 , and selecting the n-type dopant to comprise at least one of selenium and tellurium; disposing the first bonding layer and the second bonding layer between the first element and the second element ; and attaching the first element and the second element to one another at a bonding interface disposed between the first bonding layer and the second bonding layer ; wherein doping the first bonding layer and the second bonding layer with an n-type dopant reduces a wavelength of an absorption edge of the first bonding layer and the second bonding layer by at least two hundred nanometers as compared to the undoped first bonding layer and second bonding layer ; wherein forming each of the first bonding layer and the second bonding further comprises epitaxially growing the first bonding layer and the second bonding layer ; and wherein epitaxially growing the first bonding layer and the second bonding further comprises, epitaxially growing at least one bonding surface having a surface root mean square, rms, roughness of less than 0.5 nm as-grown. <EOS>