A solar cell can include a silicon semiconductor substrate; an oxide layer on a first surface of the silicon semiconductor substrate; a polysilicon layer on the oxide layer; a diffusion region at a second surface of the silicon semiconductor substrate; a dielectric film on the polysilicon layer; a first electrode connected to the polysilicon layer through the dielectric film; a passivation film on the diffusion region; and a second electrode connected to the diffusion region through the passivation film.

The present application relates to a passivating contact structure and a preparation method thereof, and a solar cell and a preparation method thereof. In the method for preparing the passivating contact structure, a tunnel layer is formed on a side of a substrate; an initial stack structure is formed on a side of the tunnel layer away from the substrate. The initial stack structure includes polysilicon layers and a doped layer alternately stacked. In the initial stack structure, an innermost layer is most adjacent to the tunnel layer, an outermost layer is most away from the tunnel layer, the innermost layer and the outermost layer are both polysilicon layers. The doped layer is a polysilicon material layer doped with a dopant. The dopant is activated, such that the dopant diffuses into the polysilicon layers, thereby transforming the initial stack structure into a doped stack structure with uniform distribution of dopant.

The present application relates to a passivating contact structure and a preparation method thereof, and a solar cell and a preparation method thereof. In the method for preparing the passivating contact structure, a tunnel layer is formed on a side of a substrate; an initial stack structure is formed on a side of the tunnel layer away from the substrate. The initial stack structure includes polysilicon layers and a doped layer alternately stacked. In the initial stack structure, an innermost layer is most adjacent to the tunnel layer, an outermost layer is most away from the tunnel layer, the innermost layer and the outermost layer are both polysilicon layers. The doped layer is a polysilicon material layer doped with a dopant. The dopant is activated, such that the dopant diffuses into the polysilicon layers, thereby transforming the initial stack structure into a doped stack structure with uniform distribution of dopant.

Provided are a back-contact battery and a manufacturing method thereof, and a photovoltaic module, which includes a silicon substrate with a front surface and a back surface; a first semiconductor layer with a second semiconductor opening region arranged back surface; and a second semiconductor layer. The back-contact battery further includes multiple insulating layers arranged at intervals along an X-axis direction of the back surface, wherein the insulating layers are arranged on the outer surface of the second semiconductor layer. In the X-axis direction, the insulating layer spans a side-surface edge of the second semiconductor opening region with both ends extending, respectively; the insulating layer has a span length W12 on the second semiconductor opening region, and the insulating layer has a span length W11 on the first semiconductor layer, satisfying a condition: W12:W11=0.1-10:1.

Provided are a back-contact battery and a manufacturing method thereof, and a photovoltaic module, which includes a silicon substrate with a front surface and a back surface; a first semiconductor layer with a second semiconductor opening region arranged back surface; and a second semiconductor layer. The back-contact battery further includes multiple insulating layers arranged at intervals along an X-axis direction of the back surface, wherein the insulating layers are arranged on the outer surface of the second semiconductor layer. In the X-axis direction, the insulating layer spans a side-surface edge of the second semiconductor opening region with both ends extending, respectively; the insulating layer has a span length W12 on the second semiconductor opening region, and the insulating layer has a span length W11 on the first semiconductor layer, satisfying a condition: W12:W11=0.1-10:1.

This application provides a heterojunction solar cell and a preparation method. The heterojunction solar cell includes: a silicon substrate being n-type or p-type doped, and having a front surface and a back surface opposite to each other; a first passivation layer and a second passivation layer sequentially located on the front surface of the silicon substrate; a third passivation layer and a fourth passivation layer sequentially located on the back surface of the silicon substrate; a silicon oxycarbide layer located on a surface of the fourth passivation layer away from the silicon substrate, wherein the silicon oxycarbide layer is n-type or p-type doped to form PN junction with the silicon substrate, an atomic percentage of carbon is greater than an atomic percentage of oxygen in the silicon oxycarbide layer. The heterojunction solar cell of the present application improves the performance of the solar cell. The carbon and the oxygen in the silicon oxycarbide layer have a fixed effect on the hydrogen, which is beneficial for reducing the loss of hydrogen.

A method for manufacturing a solar cell which simplifies the formation of a transparent electrode layer. The method includes forming conductive semiconductor layers on the back surface side of a substrate, forming a transparent conductive film on the conductive semiconductor layers, forming an uncured film of a metal electrode layer on the conductive semiconductor layers, patterning the transparent conductive film to form transparent electrode layers, and forming the metal electrode layers, in this order. In the metal electrode layer uncured film forming, a printing material is printed and dried to form the uncured film of the metal electrode layer; in the transparent electrode layer forming, the uncured film of the metal electrode layer is used as a mask to pattern the transparent conductive film; and in the metal electrode layer forming, the uncured film of the metal electrode layer is fired and cured to form the metal electrode layers.

The present disclosure discloses a preparation method for a solar cell and a solar cell. The preparation method for a solar cell comprises: locally forming a tunnel silicon oxide layer and an N-type doped polysilicon layer on a front surface of a P-type silicon substrate, wherein the N-type doped polysilicon layer is stacked on the tunnel silicon oxide layer; immersing the P-type silicon substrate having the tunnel silicon oxide layer and the N-type doped polysilicon layer locally formed on the front surface into an electroplating solution, irradiating the front surface of the P-type silicon substrate with light for a set duration so as to grow a front metal electrode on the N-type doped polysilicon layer, and removing a metal remaining on the front surface of the P-type silicon substrate by etching, wherein the width of the front metal electrode is the same as the width of the N-type doped polysilicon layer. The preparation method may omit an alignment operation in a metal electrode preparation process, thereby effectively reducing a difficulty in a preparation process of a local passivated contact emitter.

A solar cell includes a silicon substrate, a first doped region, and a second doped region. The first doped region includes a first passivated contact region on the silicon substrate and a second passivated contact region on the first passivated contact region. The first passivated contact region includes a first doped layer, a first passivation layer, and a second doped layer. The second passivated contact region includes a second passivation layer and a third doped layer. The second doped region includes a third passivation layer. Each of the first and third passivation layers includes a porous structure. One of the first and second doped regions is a P-type doped region, the other of the first and second doped regions is an N-type doped region, and a hole density of a corresponding passivation layer in the P-type doped region is greater than that in the N-type doped region.

A tandem photovoltaic device includes: an upper cell unit, a lower cell unit and a tunnel junction positioned between the upper cell unit and the lower cell unit; the tunnel junction includes an upper transport layer, a lower transport layer, and an intermediate layer positioned between the upper transport layer and the lower transport layer, the intermediate layer is an ordered defect layer, or, the intermediate layer is a continuous thin layer, or, the intermediate layer includes a first layer in contact with the lower transport layer and a second layer in contact with the upper transport layer; a doping concentration of the first layer is 10-10,000 times of a doping concentration of the lower transport layer, and the doping concentration of the first layer is less than 10.sup.21 cm.sup.3; a doping concentration of the second layer is 10-10,000 times of a doping concentration of the upper transport layer.