Method for production of a single-sided contact solar cell and single-sided contact solar cell

A method of fabricating a single-side contacted solar cell including at least one absorber layer and one emitter layer, the absorber layer and the emitter layer including semiconductor materials, the absorber layer having one of a p- or n-type doping, the emitter layer having one of a p- or n-type doping that is the opposite type doping as the doping of the absorber layer, the p- or n-type doping of the absorber and emitter layers deposited over an entire surface of each of the absorber the emitter layers, wherein excess majority and minority charge carriers produced in the absorber layer by light incidence are separated at a pn junction between the absorber and emitter layers, the majority charge carriers collected and drained away from the absorber layer via a contacting system, and the minority charge carriers are collected and drained away from the absorber layer by the emitter layer and a another contacting system, both contacting systems residing on the same side of the solar cell, the method comprising the steps of:

• I. providing an unpatterned absorber layer;
• II. applying a first contacting system in the form of a contact grid to a first side of the absorber layer, wherein the contact grid is surface-area optimized such that it collects majority charge carriers;
• III. providing, over an entire exposed surface of the contact grid, an electrically non-conductive insulation layer configured to prevent charge carriers from tunneling therethrough;
• IV. depositing an emitter layer in a layer thickness such that minority charge carriers reach a side of the emitter layer facing away from the absorber layer without suffering appreciable ohmic losses, the emitter layer including a semiconductor material that defines a pn junction relative to the absorber layer, the pn junction passivating at a maximum boundary surface recombination rate of excess charge carriers of 105 recombinations/cm2s;
• V. applying a second contacting system as a planar contact layer to a side of the emitter layer facing away from the absorber layer, and
• VI. electrically contacting the contact grid and the contact layer.

A single-side contacted solar cell, comprising:

• at least one absorber layer;
• and
• an emitter layer,
• wherein the absorber layer and the emitter layer include a semiconductor material, the absorber layer having one of a p- or n-type doping, the emitter layer having one of a p- or n-type doping that is the opposite type doping as the doping of the absorber layer, the p- or n-type doping of the absorber and emitter layers deposited over an entire surface of each of the absorber the emitter layers,
• wherein excess majority and minority charge carriers produced in the absorber layer by light incidence are separated at a pn junction between the absorber and emitter layers, the majority charge carriers collected and drained away from the absorber layer via a first contacting system, and the minority charge carriers are collected and drained away from the absorber layer by the emitter layer and a second contacting system, both the first and second contacting systems residing on a same side of the solar cell,
• wherein, the first contacting system is a contact grid that is surface-area optimized such that it collects the majority charge carriers and is electrically isolated from the emitter layer by an insulation layer, the insulation layer preventing charge carriers from tunneling therethrough, the contact grid disposed between the absorber layer and the emitter layer, and the second contacting system is a planar contact layer disposed on a side of the emitter layer facing away from the absorber layer, the emitter layer made of a semiconductor material that defines the pn junction relative to the absorber layer, the pn junction passivating at a maximum boundary surface recombination rate of the excess charge carriers of 105 recombinations/cm2s.