Crystalline solar cell comprising a transparent, conductive layer between the front-side contacts and method for producing such a solar cell

A method of manufacturing a crystalline solar cell, comprising:

• providing a semiconductor material having a first region and a second region the first region and the second region being doped in such a way that there is a pn junction between the first region and the second region;
• producing a first surface passivation layer on a first surface of the semiconductor material, the first surface passivation layer being configured such that charge carriers from the first region of the semiconductor material pass through the first surface passivation layer, and only the first region of the semiconductor material bordering on the first surface;
• applying a first optically opaque, electrically conductive material to the first surface passivation layer in first lateral regions of the first surface of the semiconductor material such that the first surface passivation layer is positioned between the first optically opaque, electrically conductive material and the first region of the semiconductor material, to produce at least one direct or indirect electrically conductive contact between the first optically opaque, electrically conductive material and the first region of the semiconductor material in the first lateral regions of the first surface of the semiconductor material;
• applying a layer of a first optically transparent, electrically conductive material to the first surface passivation layer in second lateral regions of the first surface of the semiconductor material after the first optically opaque, electrically conductive material has been applied, electrically conductive contact between the layer made of the first optically transparent, electrically conductive material and the first optically opaque, electrically conductive material and also electrically conductive contact between the layer made of the first optically transparent, electrically conductive material and the first region of the semiconductor material being produced, the second lateral regions being different from the first lateral regions, and the first optically transparent, electrically conductive material being configured to collect charge carriers that pass through the first surface passivation layer from the first region of the semiconductor material in the second lateral regions and dissipate them to the first optically opaque, electrically conductive material of the at least one electrically conductive contact;
• and
• applying a second optically opaque, electrically conductive material in first lateral regions of a second surface of the semiconductor material, and producing at least one direct or indirect electrically conductive contact between the second optically opaque, electrically conductive material and the second region of the semiconductor material in the first lateral regions of the second surface of the semiconductor material, only the second region of the semiconductor material bordering on the second surface, and the second surface of the semiconductor material being opposite the first surface of the semiconductor material,
• wherein a thermal treatment step at a temperature in the range of 200° C. to 560° C. is performed after applying the layer of the first optically transparent, electrically conductive material to the first surface passivation layer in the second lateral regions of the first surface of the semiconductor material.

A method of Method for manufacturing a crystalline solar cell, comprising:

• providing a semiconductor material having a first region and a second region the first region and the second region being doped in such a way that there is a pn junction between the first region and the second region;
• producing a first surface passivation layer on a first surface of the semiconductor material that is configured such that charge carriers from the first region of the semiconductor material pass therethrough, only the first region of the semiconductor material bordering on the first surface;
• applying a first optically opaque, electrically conductive material over the first surface passivation layer in first lateral regions of the first surface of the semiconductor material to produce at least one direct or indirect electrically conductive contact between the first optically opaque, electrically conductive material and the first region of the semiconductor material in the first lateral regions of the first surface of the semiconductor material;
• selectively applying a layer of a first optically transparent, electrically conductive material over the first surface passivation layer only in second lateral regions of the first surface of the semiconductor material after the first optically opaque, electrically conductive material has been applied, electrically conductive contact between the layer made of the first optically transparent, electrically conductive material and the first optically opaque, electrically conductive material and also electrically conductive contact between the layer made of the first optically transparent, electrically conductive material and the first region of the semiconductor material being produced, the second lateral regions being different from the first lateral regions, wherein the first optically transparent, electrically conductive material is configured to collect charge carriers that pass through the first surface passivation layer from the first region of the semiconductor material in the second lateral regions and dissipate them to the first optically opaque, electrically conductive material of the at least one electrically conductive contact, and wherein the layer of the first optically transparent, electrically conductive material is applied using a PECVD method with a remote microwave plasma and a temperature in the range of 100° C. to 400° C.;
• and
• applying a second optically opaque, electrically conductive material in first lateral regions of a second surface of the semiconductor material, and producing at least one direct or indirect electrically conductive contact between the second optically opaque, electrically conductive material and the second region of the semiconductor material in the first lateral regions of the second surface of the semiconductor material, only the second region of the semiconductor material bordering on the second surface, and the second surface of the semiconductor material being opposite the first surface of the semiconductor material,
• wherein a thermal treatment step at a temperature in the range of 200° C. to 560° C. is performed after applying the layer of the first optically transparent, electrically conductive material to the first surface passivation layer in second lateral regions of the first surface of the semiconductor material.