A high absorption photovoltaic material and method of making the material for use in a solar cell are disclosed. The photovoltaic material includes a surface modified with a layer of repeating photonic crystal structures. The photonic crystal structures are approximately inverse conically shaped and have a curved sidewall that has an approximately Gaussian shape. The photonic crystal structures generally have a high vertical depth and sidewall angle. The structures also have a gradient refractive index profile and exhibit the parallel-to-interface refraction light trapping effect. An anti-reflective coating is disposed over the photonic crystal structure layer. The photovoltaic material exhibits near unity light absorption over a broad range of visible and near infrared wavelengths and incidence angles, even at reduced thicknesses. The photovoltaic structures are formed via a combined photolithography and reactive-ion etching method at low power with a gas mixture having a high ratio of an etchant component to a passivation component.

A solar cell includes a silicon substrate, a passivation layer, a first protection layer, a second protection layer, and a third protection layer. The material of the passivation layer is aluminum oxide, and the passivation layer is on the lower surface of the silicon substrate. The material of the first protection layer is silicon oxynitride, and the first protection layer is on a surface of the passivation layer opposite to the silicon substrate. The material of the second protection layer is silicon nitride, and the second protection layer is on a surface of the first protection layer opposite to the passivation layer. The material of the third protection layer is silicon oxynitride or silicon oxide, and the third protection layer is on a surface of the second protection layer opposite to the first protection layer.

An InGaN/GaN multiple quantum well blue light detector combined with embedded electrode and passivation layer structure and a preparation method and an application thereof are provided. The detector includes: a Si substrate, an AlN/AlGaN/GaN buffer layer, a u-GaN/AlN/u-GaN/SiN.sub.x/u-GaN buffer layer, an n-GaN buffer layer, an InGaN/GaN superlattice layer and an InGaN/GaN multiple quantum well layer in sequence from bottom to top. The multiple quantum well layer has a groove structure, a mesa and a groove of the multiple quantum well layer are provided with a Si.sub.3N.sub.4 passivation layer. The passivation layer in the groove is provided with a first metal layer electrode with a semicircular cross section, and the passivation layer on the mesa is provided with second metal layer electrode.

The present disclosure relates to a photodiode, a method for preparing the same, and an electronic device. The photodiode includes: a first electrode layer and a semiconductor structure that are stacked, a surface of the semiconductor structure away from the first electrode layer having a first concave-convex structure; and a second electrode layer arranged on a surface of the semiconductor structure away from the first electrode layer, a surface of the second electrode layer away from the first electrode layer having a second concave-convex structure.

A multijunction solar cell includes an upper solar subcell, a bottom solar subcell adjacent to the upper solar subcell, a layer of light scattering elements below and directly adjacent to the bottom solar subcell, and a metallic layer disposed below and adjacent to the layer of light scattering elements.

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.

A tandem photovoltaic device and production method. The tandem photovoltaic device includes: an upper battery cell and a lower battery cell, and a tunnel junction located between the upper battery cell and the battery cell; the lower battery is a crystalline silicon cell; the tunnel junction includes: an upper crystalline silicon layer, a lower crystalline silicon layer and an intermediate layer located between the upper crystalline silicon layer and the lower crystalline silicon layer; the upper crystalline silicon layer, the lower crystalline silicon layer and the intermediate layer are in direct contact, and the doping types of the upper crystalline silicon layer and the lower crystalline silicon layer are opposite; the doping concentration of the upper crystalline silicon layer at the interface with the intermediate layer and the doping concentration of the lower crystalline silicon layer at the interface with the intermediate layer are greater than or equal to 10.sup.18 cm.sup.−3.

Provided is a solar cell and a photovoltaic module. The solar cell includes a silicon substrate, and the silicon substrate includes a front surface and a back surface arranged opposite to each other. P-type conductive regions and N-type conductive regions are alternately arranged on the back surface of the silicon substrate. Front surface field regions are located on the front surface of the silicon substrate and spaced from each other. The front surface field regions each corresponds to one of the P-type conductive regions or one of the N-type conductive regions. At least one front passivation layer is located on the front surface of the silicon substrate. At least one back passivation layer is located on surfaces of the P-type conductive regions and N-type conductive regions.

An imaging device may include single-photon avalanche diodes (SPADs). To improve the sensitivity and signal-to-noise ratio of the SPADs, light scattering structures may be formed in the semiconductor substrate to increase the path length of incident light through the semiconductor substrate. The light scattering structures may include a low-index material formed in trenches in the semiconductor substrate. One or more microlenses may focus light onto the semiconductor substrate. Areas of the semiconductor substrate that receive more light from the microlenses may have a higher density of light scattering structures to optimize light scattering while mitigating dark current.

A method for producing a textured structure of a crystalline silicon solar cell is provided, including the following steps: (1) forming a porous layer structure on a surface of a silicon wafer; (2) then cleaning with a first alkaline chemical solution; (3) removing residual metal particles with a cleaning solution; (4) and then etching the surface with a first chemical etching solution to obtain the textured structure of the crystalline silicon solar cell. The method greatly prolongs the lifetime of the mixed solution of hydrofluoric acid and nitric acid and ensures the stability and uniformity of the textured structure.