A tandem cell and a manufacturing method thereof are provided in the present disclosure, so as to improve hole transmission performance of the tandem cell. The tandem cell includes a bottom cell, a hole transporting layer formed on the bottom cell, a perovskite absorbing layer formed on the hole transporting layer, and a transparent conducting layer formed above the perovskite absorbing layer. A material of the hole transporting layer includes a semiconductor material with a p-type delafossite structure, and a valence band top energy level of the hole transporting layer sequentially decreases in a direction away from the bottom cell, which has dual functions of carrier transport and carrier recombination, so as to simplify a cell structure and optimize the photoelectric conversion efficiency. The tandem cell and the manufacturing method thereof according to the present disclosure are used for manufacturing the tandem cell.

An imaging element (photoelectric conversion element) includes a photoelectric conversion unit formed by laminating a first electrode 21, a photoelectric conversion layer 23A, and a second electrode 22. Between the first electrode 21 and the photoelectric conversion layer 23A, a composite oxide layer 23B containing indium-gallium-zinc composite oxide is formed. The composite oxide layer 23B includes a first layer 23B.sub.1 adjacent to the first electrode 21 and a second layer 23B.sub.2 adjacent to the photoelectric conversion layer 23A. The first layer 23B.sub.1 has a higher indium composition than the second layer 23B.sub.2, or the first layer 23B.sub.1 has a higher gallium composition than the second layer 23B.sub.2, or the first layer 23B.sub.1 has a higher zinc composition than the second layer 23B.sub.2.

An imaging element (photoelectric conversion element) includes a photoelectric conversion unit formed by laminating a first electrode 21, a photoelectric conversion layer 23A, and a second electrode 22. Between the first electrode 21 and the photoelectric conversion layer 23A, a composite oxide layer 23B containing indium-gallium-zinc composite oxide is formed. The composite oxide layer 23B includes a first layer 23B.sub.1 adjacent to the first electrode 21 and a second layer 23B.sub.2 adjacent to the photoelectric conversion layer 23A. The first layer 23B.sub.1 has a higher indium composition than the second layer 23B.sub.2, or the first layer 23B.sub.1 has a higher gallium composition than the second layer 23B.sub.2, or the first layer 23B.sub.1 has a higher zinc composition than the second layer 23B.sub.2.

The present disclosure relates to a method for manufacturing a monolithic tandem solar cell in which a perovskite solar cell is laminated and bonded on a silicon solar cell. According to the present disclosure, a first microporous precursor thin film is formed through a sputtering method on a substrate having an unevenly structured texture and then a halide thin film is formed on the first microporous precursor thin film to form a perovskite absorption layer, whereby light reflectance can be reduced and a path of light can be increased, and accordingly a light absorption rate can be increased.

A solar cell includes a first photoelectric conversion part, a second photoelectric conversion part, a first electrode, and a second electrode. The first photoelectric conversion part includes a photoelectric conversion layer containing a perovskite compound, a first transport layer, and a second transport layer. The second photoelectric conversion part is arranged below the second transport layer of the first photoelectric conversion part and has a different material or structure from the first photoelectric conversion part. The first electrode is electrically connected to the first photoelectric conversion part on one surface of the first photoelectric conversion part, and the second electrode is electrically connected to the second photoelectric conversion part below the second photoelectric conversion part. The first electrode has a stacking structure of at least two layers, and the second electrode is formed as a single layer.

A solar cell includes a first photoelectric conversion part, a second photoelectric conversion part, a first electrode, and a second electrode. The first photoelectric conversion part includes a photoelectric conversion layer containing a perovskite compound, a first transport layer, and a second transport layer. The second photoelectric conversion part is arranged below the second transport layer of the first photoelectric conversion part and has a different material or structure from the first photoelectric conversion part. The first electrode is electrically connected to the first photoelectric conversion part on one surface of the first photoelectric conversion part, and the second electrode is electrically connected to the second photoelectric conversion part below the second photoelectric conversion part. The first electrode has a stacking structure of at least two layers, and the second electrode is formed as a single layer.

A tandem photovoltaic structure including, from the rear face to the front face: a first SHJ solar cell comprising a first layer of P-type doped amorphous silicon and a substrate of N-type doped crystalline silicon, a junction layer, a second perovskite-type solar cell comprising an active layer and a second P-type layer, the junction layer being made of N-type TCO and being in direct contact either with the second P-type layer or with the first P-type layer, one amongst the first or second solar cell also comprising an N-type layer, the junction layer serving as an N-type layer in the other one amongst the first or second solar cell.

A tandem photovoltaic structure including, from the rear face to the front face: a first SHJ solar cell comprising a first layer of P-type doped amorphous silicon and a substrate of N-type doped crystalline silicon, a junction layer, a second perovskite-type solar cell comprising an active layer and a second P-type layer, the junction layer being made of N-type TCO and being in direct contact either with the second P-type layer or with the first P-type layer, one amongst the first or second solar cell also comprising an N-type layer, the junction layer serving as an N-type layer in the other one amongst the first or second solar cell.

A tandem photovoltaic device includes: a tunnel junction between an upper cell unit and a lower cell unit. The lower cell unit is a crystalline silicon cell. The tunnel junction includes: a carrier transport layer, a crystalline silicon layer, and an intermediate layer located between the carrier transport layer and the crystalline silicon layer. The carrier transport layer is a metal oxide layer. The intermediate layer includes a tunneling layer. The crystalline silicon layer has a doping concentration greater than or equal to 10.sup.17 cm.sup.?3. The carrier transport layer is in direct contact with a shadow surface of the upper cell unit. If the crystalline silicon layer is a p-type crystalline silicon layer, a first energy level is close to a second energy level. If the crystalline silicon layer is an n-type crystalline silicon layer, a third energy level is close to a fourth energy level.

Provided are a solar cell and a manufacturing method thereof, and a photovoltaic module. The solar cell includes: a bottom cell, a perovskite top cell, an inter layer between the bottom cell and the perovskite top cell, and a back electrode located on a back surface of the bottom cell. The perovskite top cell includes a hole transport layer, a perovskite layer, an electron transport layer, and a conductive structure stacked sequentially. The conductive structure includes at least one stack each including a first conductive layer and a second conductive layer located between the first conductive layer and the electron transport layer. The first conductive layer includes a first transparent conductive film. The second conductive layer includes a metal conductive film in a metallization region and a second transparent conductive film in a non-metallization region.