NANOSTRUCTURED ORGANIC SOLAR CELLS
Solar cells having at least one N-type material layer and at least one P-type material layer forming a patterned p-n junction are described. A conducting layer may provide electrical communication between the p-n junction and an electrode layer.
1 . A solar cell comprising:
a first electrode layer;
a patterned layer positioned on the first electrode layer, the patterned layer having a plurality of protrusions and a plurality of recessions formed by a first imprint lithography template having sub-100 nanometer resolution;
a conducting layer deposited on the patterned layer and in electrical communication with the first electrode layer;
a N-type material layer deposited on the conducting layer forming a plurality of pillars and a plurality of recesses; and,
a P-type material layer deposited on at least a portion of the N-type material layer, the P-type material layer and the N-type material layer forming at least one patterned P-N junction.
2 . The solar cell of claim 1 wherein at least one pillar is tapered.
3 . The solar cell of claim 2 wherein tapered pillar is substantially conical.
4 . The solar cell of claim 1 wherein at least one pillar is formed of at least two tiers.
5 . The solar cell of claim 1 further comprising a second electrode layer positioned on the P-type material layer.
6 . The solar cell of claim 5 wherein the second electrode layer is a metal grid.
7 . The solar cell of claim 1 further comprising:
a second N-type material layer positioned on the P-type material layer, the second N-type material layer formed by a second template and having a plurality of pillars and a plurality of recesses.
8 . The solar cell of claim 7 , wherein the first template has a first pattern and the second template has a second pattern, the first pattern differing from the second pattern.
9 . The solar cell of claim 7 further comprising a pad connecting the N-type material layer and the second N-type material.
10 . The solar cell of claim 9 , further comprising a photovoltaic material layer positioned between pad and N-type material layer.
11 . The solar cell of claim 10 , further comprising a photovoltaic material layer positioned between pad and second N-type material layer.
12 . The solar cell of claim 7 , wherein the P-type material layer and the second N-type material layer are in electrical communication with the first electrode layer.
13 . The solar cell of claim 7 , further comprising a second P-type material layer deposited on the second N-type material layer.
14 . The solar cell of claim 13 , wherein the first P-type material layer is formed of material having a first absorption range and second P-type material layer is formed of material having a second absorption range, wherein first absorption range is different from second absorption range.
15 . The solar cell of claim 1 , wherein the N-type material layer is non-contiguous forming at least one gap.
16 . The solar cell of claim 15 , wherein the conducting layer is deposited within the gap such that the conducting layer is in electrical communication with the first electrode layer.
17 . The solar cell of claim 1 , wherein at least one pillar is further defined by a length of less than approximately twice the diffusion length of excitons.
18 . The solar cell of claim 1 , wherein at least one pillar is further defined by a length less than the diffusion length of excitons.
19 . The solar cell of claim 1 , wherein recesses are sequentially interspersed between pillars.
20 . The solar cell of claim 19 , wherein the P-type material layer is deposited within recesses of the N-type material layer.
21 . A solar cell comprising:
a patterned layer having a plurality of protrusions and a plurality of recessions formed by an imprint lithography template having sub-100 nanometer resolution; and,
a conducting or semi-conducting layer deposited on the patterned layer forming a high surface area electronic material.