Disclosed is a solar cell including a semiconductor substrate, and a dopant layer disposed over one surface of the semiconductor substrate and having a crystalline structure different from that of the semiconductor substrate, the dopant layer including a dopant. The dopant layer includes a plurality of semiconductor layers stacked one above another in a thickness direction thereof, and an interface layer interposed therebetween. The interface layer is an oxide layer having a higher concentration of oxygen than that in each of the plurality of semiconductor layers.

Methods of fabricating solar cells with tunnel dielectric layers are described. Solar cells with tunnel dielectric layers are also described.

Method for manufacturing avalanche photodetector, including forming multiplication layer on wafer; etching closed groove on surface of the multiplication layer, so that depth of the closed groove is greater than or equal to thickness of the multiplication layer, but less than total thickness of the wafer and multiplication layer combined; filling the groove with highly-doped polycrystalline silicon of same conductivity type as multiplication layer; forming, on upper surface of multiplication layer, inside groove, avalanche amplifier as mesa structure, by forming contact layer on multiplication layer, while simultaneously forming photoconverter outside contact layer, and etching away portion of multiplication layer in the photoconverter to depth less than thickness of the multiplication layer; forming dielectric layer on multiplication layer where etching took place, its thickness equal to the depth of multiplication layer that was etched away; forming first electrode of transparent material on surfaces of contact and dielectric layers; forming second electrode.

The present disclosure provides a hybrid heterojunction solar cell, a cell component, and a preparation method, the hybrid heterojunction solar cell comprises a semiconductor substrate having a substrate front surface and a substrate back surface opposite to each other, wherein the substrate front surface is close to a light-facing side of the cell and the substrate back surface is close to a backlight side of the cell; at least two composite layers located on one side of the substrate front surface, each composite layer includes a multi-layer structure of a tunneling layer and a doped polysilicon layer sequentially arranged in a direction gradually away from the substrate front surface. The hybrid heterojunction solar cell, cell component and a preparation method provided by this disclosure can achieve a stable passivation effect on the cell surface, reduce light absorption in the non-metallic areas of the cell, and achieve better process control at the same time.

In one aspect, a preparation method for a solar cell includes: providing a silicon wafer substrate having a first surface and a second surface opposite to the first surface; forming a silicon-containing film on the first surface of the silicon wafer substrate; patterning the silicon-containing film on the first surface by laser to form a patterned region; placing the silicon wafer substrate having the silicon-containing film and the patterned region into an alkaline solution containing a strong monobasic base to obtain a pre-treated silicon wafer substrate, and placing the pre-treated silicon wafer substrate into a texturing liquid containing a strong monobasic base for texturing treatment, wherein a concentration of the strong monobasic base in the alkaline solution is greater than a concentration of the strong monobasic base in the texturing liquid.

This disclosure provides a back contact solar cell and a method for manufacturing a back contact solar cell. In one example, a back contact solar cell includes a silicon substrate having first regions and second regions alternately distributed on a back surface of the silicon substrate, and a first doped semiconductor layer formed on a first region on the back surface of the silicon substrate. A groove structure concaving inward the silicon substrate relative to a surface of the first region is formed on a second region. An end portion of the first doped semiconductor layer adjacent to the second region is arranged in a suspended manner.

Disclosed in the present invention are an all-black crystalline silicon solar cell and a preparation method therefor, and a photovoltaic module. The preparation method comprises the following steps: (1) depositing a film layer on the front face of a silicon wafer by means of a PECVD method so as to obtain a silicon wafer having a coated front face, wherein the film layer is of a laminated structure and comprises an innermost SiN.sub.x layer having a thickness of 20 nm or more; (2) subjecting the resulting silicon wafer having the coated front face to back-face PECVD and laser beam grooving so as to obtain a coarse silicon solar cell; and (3) subjecting the resulting coarse silicon solar cell to silk-screen printing and electron injection to then obtain an all-black crystalline silicon solar cell. In the preparation method provided in the present application, the film layer is deposited on the front face of the silicon wafer by means of the PECVD method, the material and thickness of the innermost SiNx layer are designed, and particularly when the thickness thereof is 20 nm or more, the absorption and reflection effects of incident light on the surface of the cell are influenced, such that the incident light is almost completely absorbed, and only an extremely small amount of the incident light is reflected; therefore, the all-black crystalline silicon solar cell is obtained.

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 solar cell, a method for manufacturing solar cell, and a photovoltaic module. The solar cell includes: a semiconductor substrate; a tunneling layer located over a rear surface of the semiconductor substrate; a hydrogen barrier layer located over a surface of the tunneling layer; a lightly doped conductive layer located over a surface of the hydrogen barrier layer; and grid-shaped doped conductive layers located on at least part of a surface of the lightly doped conductive layer, wherein each of the grid-shaped doped conductive layers includes a heavily doped conductive layer and a metal barrier layer that are stacked on one another.

The disclosure discloses a solar cell and a preparation method for a solar cell. The preparation method for a solar cell comprises: sequentially forming a tunnel silicon oxide layer, an N-type doped polysilicon layer, and a front metal layer in an entire fashion on a front surface of a P-type silicon substrate; subjecting the entire front metal layer to a photoetching process to form a patterned front fine gate electrode; subjecting the tunnel silicon oxide layer and the N-type doped polysilicon layer in a region not covered by the front fine gate electrode to chemical etching to form a local tunnel silicon oxide layer and a local N-type doped polysilicon layer, wherein the widths of the local tunnel silicon oxide layer and the local N-type doped polysilicon layer are the same as the width of the front fine gate electrode. The preparation method may achieve an automatic and precise alignment of the front fine gate electrode with a local tunnel oxide passivated layer and a local polysilicon layer, thereby effectively reducing a difficulty in a preparation process of a local passivated contact emitter while ensuring the efficiency of the solar cell.