Patent ID: 9680117
Date: 2017-06-13
CPC Classifications: H01L,Y02E

Claim:
1. A thin film organic photovoltaic solar cell comprising: a bottom electrode layer; an electron transport layer disposed thereon and including a one-dimensional metallic bottom nanograting embedded therein; an organic active bilayer disposed thereon comprising an acceptor layer and a donor layer, the acceptor and donor layers being formed of electrically conductive organic polymers selected to form a heterojunction at an interface between the acceptor and donor layers; and a transparent top conducting electrode layer disposed thereon, the top electrode layer comprising a transparent conductive material and a one-dimensional metallic top nanograting embedded therein; wherein the nanogratings have thicknesses selected to excite surface plasmonic resonances of all light polarizations at an interface between the nanogratings and active bilayer from incident light on the transparent conducting electrode layer for increasing photon absorption in the active bilayer; and wherein the top nanograting is arranged in a different orientation than the bottom nanograting forming a composite nanograting structure possessing two-dimensional symmetry in top plane view having polarization-independent optical absorption.