A solar cell and a manufacturing method thereof, a photovoltaic module, and a photovoltaic system. The manufacturing method includes: providing a substrate; and dividing a second surface of the substrate into a first region, a second region, and an isolation region; sequentially stacking a first tunnel oxide layer, a first intrinsic amorphous silicon layer, a second tunnel oxide layer, and a second intrinsic amorphous silicon layer on the second surface of the substrate; removing the second intrinsic amorphous silicon layer and the second tunnel oxide layer located in the second region; doping the first intrinsic amorphous silicon layer and the second intrinsic amorphous silicon layer located in the first region with a first element, to obtain a first doped layer and a second doped layer respectively; doping the first intrinsic amorphous silicon layer located in the second region with a second element, to obtain a third doped layer; and forming an isolation structure in the isolation region, to isolate the first tunnel oxide layer located in the first region from the first tunnel oxide layer located in the second region and isolate the first doped layer and the second doped layer located in the first region from the third doped layer located in the second region.

A solar cell and a manufacturing method thereof, a photovoltaic module, and a photovoltaic system. The manufacturing method includes: providing a substrate; and dividing a second surface of the substrate into a first region, a second region, and an isolation region; sequentially stacking a first tunnel oxide layer, a first intrinsic amorphous silicon layer, a second tunnel oxide layer, and a second intrinsic amorphous silicon layer on the second surface of the substrate; removing the second intrinsic amorphous silicon layer and the second tunnel oxide layer located in the second region; doping the first intrinsic amorphous silicon layer and the second intrinsic amorphous silicon layer located in the first region with a first element, to obtain a first doped layer and a second doped layer respectively; doping the first intrinsic amorphous silicon layer located in the second region with a second element, to obtain a third doped layer; and forming an isolation structure in the isolation region, to isolate the first tunnel oxide layer located in the first region from the first tunnel oxide layer located in the second region and isolate the first doped layer and the second doped layer located in the first region from the third doped layer located in the second region.

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 metal-semiconductor contact structure is provided. The metal-semiconductor contact structure includes a doped silicon-based semiconductor layer and a metal electrode in contact with each other. A contact region between the doped silicon-based semiconductor layer and the metal electrode includes a first conductive region and a second conductive region. In the first conductive region, the metal electrode is recessed towards an inner direction of the doped silicon-based semiconductor layer to form a pit island, a silicon-based eutectic in conductive connection with the doped silicon-based semiconductor layer is provided in the pit island, and a conductive crystal in conductive connection with the silicon-based eutectic is provided. A conductive aggregate including a glass phase material and metal conductive particles is provided in the second conductive region, and the metal conductive particles have a same kind of the metal element as the conductive crystal.

A modified tunnel oxide layer and a preparation method, a TOPCon structure and a preparation method, and a solar cell are provided. The modified tunnel oxide layer is SiO.sub.x subjected to plasma surface treatment, and a Si.sup.4+ content in the SiO.sub.x is greater than or equal to above 18%. The density of the interface state subjected to plasma surface treatment decreases, and compared with the silicon oxide layer prepared in the prior arts, boron has a low diffusion rate in the modified silicon oxide layer and hence the damaging effect of the boron on the tunnel oxide layer is reduced effectively, thereby improving the integrity of the silicon oxide layer and maintaining chemical passivation effect. The modified tunnel oxide layer significantly increases the performance indexes of the TOPCon structure.

A back contact solar cell includes a semiconductor substrate, a first functional layer, a second functional layer, a laser protection layer, a first electrode structure, and a second electrode structure. The semiconductor substrate has a light-receiving surface and a shady surface. The first functional layer is formed in the first polarity region. The second functional layer is formed in the second polarity region. The laser protection layer is formed on a side of the second functional layer away from the semiconductor substrate and exposes an electrode contact region of the second functional layer. The laser protection layer includes laser absorption material. The first electrode structure is formed on a side of the first functional layer away from the semiconductor substrate. The second electrode structure is formed on a side of the second functional layer away from the semiconductor substrate, and the second electrode structure is in the electrode contact region.

A solar cell and a photovoltaic module. The solar cell includes a substrate having a first surface and a second surface arranged oppositely, the second surface including a first region, a second region, and an isolation region located between the first region and the second region; a first tunnel oxide layer, a first doped layer, a second tunnel oxide layer, and a second doped layer located in the first region and sequentially stacked in a direction away from the substrate; the first tunnel oxide layer and a third doped layer located in the second region and sequentially stacked in a direction away from the substrate; and an isolation structure located in the isolation region and configured to isolate the first tunnel oxide layer located in the first region from the first tunnel oxide layer located in the second region, the isolation structure further configured to isolate the first doped layer and the second doped layer located in the first region from the third doped layer located in the second region.

A solar cell and a photovoltaic module. The solar cell includes a substrate having a first surface and a second surface arranged oppositely, the second surface including a first region, a second region, and an isolation region located between the first region and the second region; a first tunnel oxide layer, a first doped layer, a second tunnel oxide layer, and a second doped layer located in the first region and sequentially stacked in a direction away from the substrate; the first tunnel oxide layer and a third doped layer located in the second region and sequentially stacked in a direction away from the substrate; and an isolation structure located in the isolation region and configured to isolate the first tunnel oxide layer located in the first region from the first tunnel oxide layer located in the second region, the isolation structure further configured to isolate the first doped layer and the second doped layer located in the first region from the third doped layer located in the second region.

A method of manufacturing a lead salt thin film on a substrate by seeding a substrate with a lead salt solution (e.g., PbSe, PbS, or PbTe) to form a seeded substrate comprising lead salt seed crystals, and growing the lead salt thin film upon the substrate by exposing the seeded substrate to a chemical bath comprising the lead salt solution at a predetermined growth temperature. A lead salt thin film manufactured by the process. A photonic crystal microchip comprising the lead salt thin film. A gas sensing device comprising a diode laser, a mid-infrared photodetector, and the photonic crystal microchip. A method of detecting a hydrocarbon gas, comprising exposing a gas sample to the gas sensing device, and determining the content of hydrocarbon gases in the gas sample.