Metallization patterns for photovoltaic cells
An example of an apparatus to convert light energy to electrical energy is provided. The apparatus includes a semiconductor material to absorb energy from a photon. The energy is to be converted to a current. Furthermore, the apparatus includes a positive electrode disposed on a backside of the semiconductor material to collect the current from the backside. In addition, the apparatus includes a via to connect the backside of the semiconductor material electrically to a frontside of the semiconductor material. The apparatus also includes a plurality of fingers disposed on the frontside of the semiconductor material to collect the current from the frontside. The apparatus further includes a trunkline connected to the plurality of fingers to deliver the current to the via. The trunkline is to increase a cross-sectional area toward the via to reduce parasitic resistance.
1 . An apparatus comprising:
a semiconductor material to absorb energy from a photon, wherein the energy is to be converted to a current;
a positive electrode disposed on a backside of the semiconductor material to collect the current from the backside;
a via to connect the backside of the semiconductor material electrically to a frontside of the semiconductor material;
a plurality of fingers disposed on the frontside of the semiconductor material to collect the current from the frontside; and
a trunkline connected to the plurality of fingers to deliver the current to the via, wherein the trunkline increases a cross-sectional area toward the via to reduce parasitic resistance, wherein a variation of the cross-sectional area maintains a substantially constant current density in the trunkline, wherein the cross-sectional area varies as a non-linear function with distance from the via, and wherein the non-linear function is parabolic.
2 . The apparatus of claim 1 , wherein a finger of the plurality of fingers increases a finger cross-sectional area toward the trunkline to reduce parasitic resistance.
3 . The apparatus of claim 2 , wherein a variation of the finger cross-sectional area maintains a substantially constant current density in the finger.
4 . The apparatus of claim 3 , wherein the finger cross-sectional area varies as a finger non-linear function with distance from the trunkline along the finger.
5 . The apparatus of claim 4 , wherein the finger non-linear function is parabolic.
6 . The apparatus of claim 1 , wherein the plurality of fingers are disposed in a pattern to reduce a pathway distance to the via.
7 . The apparatus of claim 6 , wherein the pattern includes each finger of the plurality of fingers disposed at an angle relative to the trunkline.
8 . The apparatus of claim 7 , wherein the angle is about 45 degrees.
9 . The apparatus of claim 1 , further comprising a plurality of connectors between adjacent fingers in the plurality of fingers to increase redundancy.