27 results about "Boron diffusion" patented technology

The purpose of this invention is to disclose a silicon wafer boron expansion process data characterization system, including a boron expansion process data module and a sheet resistance data module. The data collected by the boron expansion process data module and the data collected by the sheet resistance data module are matched using timestamps, boron expansion equipment IDs, furnace tube IDs, and graphite boat IDs. The beneficial effects of this invention are: by accurately matching the data collected by the boron expansion process data module and the sheet resistance data module using timestamps, boron expansion equipment IDs, furnace tube IDs, and graphite boat IDs, on the one hand, it ensures that the data collected by each sheet resistance data module accurately corresponds to the data collected by the boron expansion process data module, accurately reflecting the adaptability of the data collected by the boron expansion process data module and facilitating timely adjustments to the boron expansion process; on the other hand, it facilitates big data processing of the data collected by the boron expansion process data module and the sheet resistance data module.

This application belongs to the technical field of cemented carbide materials, specifically a high-toughness WC-Co cemented carbide and its preparation method. The preparation method includes: using tungsten carbide powder, cobalt powder, tantalum carbide powder, boron source, and tungsten powder as raw materials; mixing and ball-milling all the boron source, tungsten powder, and part of the cobalt powder to obtain a first slurry; mixing and ball-milling all the tungsten carbide powder, tantalum carbide powder, and the remaining cobalt powder to obtain a second slurry; mixing the first slurry and the second slurry, ball-milling, drying, and pressing; and then sintering in three stages with increased temperature to obtain the WC-Co cemented carbide. This application, through the synergistic design of "pre-alloying wet milling" and "medium-temperature heat preservation," guides the uncontrollable boron diffusion reaction process into a directional and gradual reaction path of "B→Co2B→WCoB," thereby avoiding the formation of harmful phases such as brittle WB, optimizing the microstructure of the WC-Co cemented carbide, and improving its mechanical properties.

This application relates to the field of solar cell technology, specifically providing a boron diffusion method, a solar cell, and a photovoltaic module. The boron diffusion method includes: forming a pre-doped layer and an initial doped dielectric layer stacked on a first surface of a substrate; etching the initial doped dielectric layer using an etching process to remove at least a portion of the initial doped dielectric layer; placing the substrate with at least a portion of the initial doped dielectric layer removed into a diffusion furnace, heating it to 900-980°C in an oxygen-free environment for oxygen-free propagation; maintaining the temperature at 900-980°C, introducing oxygen into the diffusion furnace for oxygen-enriched propagation, so that the pre-doped layer forms a first doped layer. The boron diffusion method in this application results in a first doped layer with a low doping concentration and a small doping depth, which is beneficial for reducing recombination losses and improving device quality and lifespan.

This invention discloses a method for preparing high sheet resistance shallow pn junction single-crystal silicon wafers based on rapid boron diffusion, comprising the following steps: S1: depositing a boron-containing precursor on the textured silicon wafer surface; S2: depositing a low-temperature oxide layer on the surface of the boron-containing precursor; S3: placing the silicon wafer with the deposited low-temperature oxide layer in a rapid thermal processing device, rapidly heating it to 1050-1350℃ at a heating rate of 5-200℃ / s, holding it at this temperature for 20-600s, and then rapidly cooling it to complete the diffusion and activation of boron atoms in the silicon wafer. This invention employs a combination of low-temperature deposition and rapid boron diffusion, which can significantly shorten the boron diffusion time, reduce energy consumption, and shorten the high-temperature processing time. It also suppresses the formation of oxygen precipitate defects at the source, eliminating problems such as black cores and black rings in batteries, and significantly improving carrier lifetime and material electrical performance.

This application relates to the field of photovoltaic cell technology, and in particular to a method for fabricating solar cells, solar cells, and photovoltaic modules. The method for fabricating the solar cell includes: providing an N-type silicon substrate; forming a boron diffusion layer and a BSG layer on the back side of the N-type silicon substrate, and dividing the back side into alternating first and second regions; performing laser processing on the first region to form multiple voids in the BSG layer; and then performing alkaline polishing to selectively etch the boron diffusion layer in the first region while retaining the BSG layer. This fabrication method, by using a laser to form voids in the BSG layer of the first region instead of direct ablation, and utilizing these voids as channels for subsequent alkaline polishing to selectively etch away the underlying boron diffusion layer while retaining the BSG layer in the first region, minimizes damage to the silicon substrate structure and reduces lateral damage to the adjacent second region caused by laser thermal effects.

The application discloses a preparation method of an N-type solar cell boron diffusion SE structure, and comprises the following steps: preparing an oxide layer on the surface of a silicon substrate, boron doping, annealing, and forming a polysilicon layer; preparing a mask on the surface of the polysilicon layer in a preset grid line area; removing the polysilicon layer and the oxide layer in the non-grid line area on the surface of the silicon substrate; and removing the mask to obtain the N-type solar cell boron diffusion SE structure. Compared with a conventional preparation method, the preparation method of the N-type solar cell boron diffusion SE structure only needs one high-temperature annealing process, causes less loss to the silicon substrate, has the advantages of simple process, convenient operation, low cost, small damage and the like, is beneficial to improving the photoelectric conversion efficiency of the cell, is beneficial to realizing large-scale production, has high use value, and has good application prospect.

A method for fabricating a solar cell and its electrode are provided, comprising the following steps: S1, texturing a silicon wafer; texturing an n-type silicon substrate; S2, performing boron diffusion on the front side of the silicon wafer, sequentially forming a boron-doped layer, a boron-rich layer, and a BSG layer; S3, processing a second region of the silicon wafer using an infrared laser, modifying the boron-rich layer in the second region to make it resistant to acid and alkali corrosion; removing the BSG layer and the boron-rich layer in the second region by wet etching, and performing a second texturing on the second region to form a second pyramid structure; S5, oxidizing the front side of the silicon wafer, forming a first mask layer in the first region of the silicon wafer and a second mask layer in the second region of the silicon wafer; wherein, the first region of the silicon wafer is the region where the front electrode is to be fabricated. The method of this invention can solve the laser damage problem of existing laser-based film-forming schemes, reduce global Auger recombination, improve passivation effects, and increase cell conversion efficiency.

The utility model relates to the field of neodymium iron boron diffusion technology, concretely relates to a kind of neodymium iron boron diffusion mixing device;Including fixed frame and the mixing frame of sliding cooperation in fixed frame;Mixing frame adopts double-layer grid structure, for the clamping mixing tank, fixed between two layers of mixing frame through connecting plate;The bottom of fixed frame is equipped with driving device, and driving device is used to drive mixing frame to slide up and down along fixed frame and mix;The side of connecting plate is fixed with sliding shaft by fixed lug welding;The both sides of fixed frame are vertically provided with mounting beam, and the sliding connecting plate is fixed on the fixed frame, the sliding sleeve is installed on the sliding connecting plate, and the sliding shaft is matched in the sliding sleeve of both sides;The utility model solves how to realize the technical problem of automatic mixing of neodymium iron boron and heavy rare earth raw materials.

The present disclosure provides a solar cell and a preparation method thereof, and belongs to the technical field of solar cells. The back surface of the solar cell has a passivation contact structure only at the position corresponding to the non-metallic region. The passivation contact structure forms an etching step with an inclination angle of 40-60 degrees at the position where the metallic region and the non-metallic region meet. The etching step with the above inclination angle can make the transition between the non-metallic region and the metallic region smoother than the vertical etching step, and is more conducive to the uniformity of the subsequent passivation film layer and the transportation of back surface carriers, thereby improving the passivation level of the solar cell. The preparation of the solar cell comprises: double-sided texturing, boron diffusion and oxidation, BSG removal and alkali etching, LPCVD and phosphorus diffusion, and back surface patterning of the N-type silicon substrate; removing the PSG on the front surface of the N-type silicon substrate, using an alkali solution and a specific anti-plating additive for RCA cleaning, and removing the tunneling oxide layer and the doped polysilicon layer on the back surface of the N-type silicon substrate corresponding to the metallic region.

This invention provides a method for achieving high sheet resistance uniformity in boron diffusion for TOPCon solar cells. The method includes sequential steps such as wafer loading, heating, vacuuming, pre-oxygenation, multi-step power supply, variable-temperature multi-step junction pushing, variable-pressure annealing, re-pressure, and wafer unloading. The variable-temperature multi-step junction pushing includes sequential oxygen-free and oxygen-containing junction pushing. The temperature of oxygen-free junction pushing is lower than that of oxygen-containing junction pushing, the time of oxygen-free junction pushing is shorter than that of oxygen-containing junction pushing, the furnace pressure during oxygen-free junction pushing is lower than that during oxygen-containing junction pushing, and the oxygen flow rate during oxygen-containing junction pushing is 18000-23000 sccm. This invention improves the uniformity of boron content distribution by introducing a variable-temperature multi-step junction pushing process that combines oxygen-free followed by oxygen-containing junction pushing with multi-step power supply and variable-pressure annealing. This results in a P+ emitter with lower surface doping concentration and shallower junction depth, while significantly improving the sheet resistance uniformity after boron diffusion, achieving high sheet resistance uniformity under high sheet resistance targets.

The utility model discloses a kind of anti-crystallization boric acid exhaust pipes of boron diffusion high-temperature furnace, including upper pipeline, lower pipeline, dust collecting barrel and heating heat tracing band, the upper end of the lower pipeline is telescopically configured in the lower end of the upper pipeline, the dust collecting barrel is detachably connected in the lower end of the lower pipeline, the heating heat tracing band is wound in the outside of the upper pipeline and lower pipeline.The utility model is connected with upper pipeline and lower pipeline by telescopic, to quickly scrape the crystallization inside pipe wall, can save the inconvenience when replacing acid exhaust pipe and the time when cleaning pipe crystallization, while the lower end of lower pipeline is detachably connected with dust collecting barrel, can quickly replace dust collecting barrel, can save maintenance time, save labor, reduce the crystallization produced by gas and pipe cold gas reaction after process, and save the crystallization fallen due to cleaning.

In one aspect, a preparation method for a solar cell includes the following steps: sequentially forming a first silicon oxide layer, an intrinsic amorphous silicon layer, a phosphorosilicate glass layer and a second silicon oxide layer on the back surface of an n-type silicon substrate; removing the phosphorosilicate glass layer and the second silicon oxide layer in a partial region of the back surface of the n-type silicon substrate; subjecting the back surface of the n-type silicon substrate to boron diffusion; forming an isolation groove at the boundary between the boron-doped polycrystalline silicon layer and the phosphorus-doped polycrystalline silicon layer; and preparing a first electrode connected to the boron-doped polycrystalline silicon layer and a second electrode connected to the phosphorus-doped polycrystalline silicon layer.

This invention discloses an optimized cleaning process for reworked BC solar cell semi-finished products before etching, relating to the field of crystalline silicon solar cell manufacturing technology. The optimized process includes Cleaning 1 → LP1 → Boron diffusion → Patterning 1 → Cleaning 2 → LP2 → Phosphorus diffusion → Patterning 2. If the polishing process encounters problems after Cleaning 1, oxidation treatment is omitted, and the oxide layer is not involved; polishing is directly repeated after Cleaning 1. If the light polishing process encounters problems after LP1, light polishing is directly repeated after Cleaning 1, with a weight reduction of 0.05g. If the boron diffusion process encounters problems after LP1, acid washing in an acid bath for 800s is performed before re-processing after Cleaning 1. A dummy wafer is activated during Patterning 1, Cleaning 2, LP2, Phosphorus diffusion, and Patterning 2 processes for double-sided etching. This invention ensures the finished product thickness, with efficiency loss within 0.02%, and does not require additional equipment.

This invention discloses a novel TOPCon cell process and production apparatus, relating to the field of crystalline silicon solar cell technology, including the following steps: S1, texturing: using an N-type monocrystalline silicon wafer as the substrate, texturing is performed on both sides of the monocrystalline silicon wafer using acid and alkali chemicals to form a pyramid structure on the surface of the monocrystalline silicon wafer; S2, boron diffusion: boron diffusion is performed on the front surface of the silicon wafer, with BCl3 as the boron source and a diffusion sheet resistance of 100-150Ω; S3, oxidation: forming BSG on the surface of the silicon wafer with a thickness of 80-120nm and a sheet resistance of 250-350Ω; S4, BSG removal and alkaline polishing: using a chain machine, the front surface of the silicon wafer is protected by a water film, and the BSG on the back and four sides of the silicon wafer is removed by using a 28%-35% HF solution by volume and a roller to carry the liquid; this invention moves the grooving laser process in the dicing step to between annealing and RCA, and the thermal damage caused by the grooving laser can be cleaned away by RCA, solving the negative effects of thermal damage without changing the preceding processes, and improving cell efficiency.

A method for fabricating a solar cell includes the following steps: forming a boron junction on a first surface of a silicon substrate; forming a tunneling passivation contact structure on a second surface of the silicon substrate; forming a first electrode on the first surface and a second electrode on the second surface; and performing laser sintering on the first and second electrodes using laser-assisted sintering technology. The "forming a boron junction" step includes: forming an oxide layer on the first surface of the silicon substrate, heating to a diffusion temperature for boron diffusion, and heating to an oxidation temperature for oxidation. In this method, the subsequent step of "forming a boron junction" involves directly heating the substrate based on the preceding step, which saves energy and shortens the process flow. The oxidation and diffusion steps are combined into one step, reducing the oxidation temperature to below 1000°C while ensuring cell efficiency and yield, thus lowering costs. Furthermore, the reduced temperature required for low-temperature oxidation extends the furnace tube's lifespan.

A method for metallizing a solar cell includes: providing a silicon substrate with a doped layer deposited thereon; depositing passivation layers on its front and back sides, printing metal paste, and sintering to form conductive grid lines; employing laser-induced metallization technology, applying a reverse bias voltage to the silicon substrate, and irradiating the silicon substrate with a laser to form ohmic contacts between the grid lines and the silicon substrate; wherein the doped layer is formed by a boron diffusion process on the silicon substrate to form a boron diffusion layer, wherein the surface concentration of the boron diffusion layer is 1×10⁻⁶. 18 cm ‑3 -5×10 18 cm ‑3 The sheet resistance is greater than or equal to 200 Ω / sq. This application utilizes laser-induced metallization technology to induce process current formation on the silicon substrate by laser irradiation, achieving direct contact between the gate line and the silicon substrate with high sheet resistance. It achieves low contact resistance under conditions of light doping and high sheet resistance, eliminating the need for selective emitter (SE) technology, reducing Auger recombination, eliminating laser-induced damage, and ensuring passivation quality.

The application discloses a kind of foamed metal foil for grain boundary diffusion, neodymium iron boron diffusion magnet and preparation method.The preparation method of the foamed metal foil for grain boundary diffusion of the application comprises the following steps:1) depositing a rare earth alloy film on the surface of a foamed metal foil sheet to obtain a coated foamed metal foil sheet;2) fold the coated foamed metal foil sheet obtained in step 1) in half, with the coated side facing in, and compress after folding to obtain a foamed metal foil for grain boundary diffusion.The foamed metal foil for grain boundary diffusion of the application enhances the adhesion of the rare earth alloy film, and when used for grain boundary diffusion, it increases the coercivity of the neodymium iron boron magnet while reducing the drop in remanence.

The application relates to the technical field of solar cells, in particular to an N-type TOPCon solar cell with anti-ultraviolet attenuation and a preparation method thereof. The front surface of the N-type TOPCon solar cell comprises an N-type silicon substrate, a boron diffusion emitter, a bottom aluminum oxide layer, an intermediate ultrathin silicon nitride layer, an intermediate ultrathin aluminum oxide layer and an outer silicon nitride layer arranged in sequence. When the conventional front surface only adopts the direct stacking of the aluminum oxide layer and the silicon nitride layer, the interface is more prone to charge disturbance, local defect accumulation and structure instability under ultraviolet irradiation. According to the application, the intermediate ultrathin silicon nitride layer and the intermediate ultrathin aluminum oxide layer are introduced, so that the ultraviolet stress originally concentrated on a single interface is dispersed into multiple nanoscale transition layers, thereby slowing down the interface instability process and inhibiting the attenuation of the passivation performance of the front surface.

This invention discloses a monitoring method for the laser processing step of solar cells. The monitoring method includes: providing a monitoring sheet, which comprises a crystalline silicon wafer, a phosphorus-doped polycrystalline silicon layer and a phosphosilicate glass layer on a first main surface of the crystalline silicon wafer, a boron diffusion layer, a boron-phosphosilicate glass layer, a first wrap-around coating, and a second wrap-around coating on a second main surface of the crystalline silicon wafer; performing intermittent laser processing on specific areas of the monitoring sheet using the laser processing step to form alternating laser-processed and non-laser-processed areas; removing the second wrap-around coating and the first wrap-around coating from the laser-processed areas; removing the boron-phosphosilicate glass layer and the boron diffusion layer from the laser-processed areas, and the second wrap-around coating, the first wrap-around coating, the boron-phosphosilicate glass layer, and the phosphosilicate glass layer on the first main surface of the crystalline silicon wafer from the non-laser-processed areas and other areas, to obtain the target monitoring sheet; inspecting the target monitoring sheet; and evaluating the laser processing step based on the inspection results. This monitoring method can reliably and effectively monitor the laser processing step.

The application discloses a kind of multi-slice local area passivation TOPCon battery and preparation method thereof, comprising the following steps: S1: etching; S2: boron diffusion; S3: oxidation; S4: photoetching; S5: alkali throwing; S6: Poly amorphous silicon doping; S7: annealing; S8: RCA cleaning; S9: ALD deposition; S10: front PECVD coating; S11: back PECVD coating; S12: screen printing; S13: test.The application covers a layer of photoresist on the front surface of the silicon wafer by printing, spin coating, transfer printing, coating and other methods, the mask layout exposes the position area of 2-slice, or 3-slice, or 4-slice, or multi-slice, then self-alignment exposure or drying is carried out, then the exposed area is etched away, the photoresist is removed and cleaned and dried, so as to increase the power of the module by only adding one photoetching equipment, avoid the high temperature damage problem of laser equipment and the high cost of laser equipment investment problem.

This invention provides a method for preparing a P-type polycrystalline silicon layer, a method for preparing a TBC (Transient Carbon Fiber) cell, and a TBC cell, specifically relating to the field of solar cell fabrication technology. The method for preparing the P-type polycrystalline silicon layer involves first preparing a polycrystalline silicon-amorphous silicon stack on an N-type crystalline silicon substrate with a first tunneling oxide layer on the back side, followed by boron diffusion to obtain a P-type polycrystalline silicon layer and a BSG (Bipolar Solid State Geographic Array) layer. The polycrystalline silicon-amorphous silicon stack includes a first polycrystalline silicon layer, a second polycrystalline silicon layer, a third polycrystalline silicon layer, and an amorphous silicon layer arranged sequentially. The polycrystalline silicon-amorphous silicon stack is prepared using a stepped cooling and boosting LPCVD (Liquid Crystallization-Voltage Continuous Chemical Deposition) process. This structure effectively alleviates the accumulation of interfacial thermal stress caused by thermal expansion mismatch, suppresses wafer warping and localized bonding during post-reaction cooling, significantly reduces the risk of mechanical scratches and fragmentation caused by inter-wafer contact in subsequent material feeding and wafer separation processes, and improves the process consistency and production line yield of the P-type polycrystalline silicon layer structure.

A boron diffusion apparatus, and a production system. In the boron diffusion apparatus, a furnace body is provided with a gas inlet and a gas outlet opposite to each other in a first direction; a first ventilation pipe is provided with a first partial pipe body extending into the furnace body; and a second ventilation pipe is provided with a second partial pipe body extending into the furnace body, the length of the second partial pipe body being greater than the length of the first partial pipe body.

This invention discloses an aluminum-containing metal foil for grain boundary diffusion, a neodymium iron boron (NdFeB) diffusion magnet, and a preparation method thereof. The aluminum-containing metal foil for grain boundary diffusion of this invention is made by depositing a rare-earth alloy thin film on the surface of an aluminum foil or an aluminum-silicon alloy foil; the rare-earth element in the rare-earth alloy thin film is selected from at least one of Tb and Pr; the alloying element in the rare-earth alloy thin film is selected from at least one of Cu, Mg, Fe, and Sn; the atomic percentage content of the rare-earth element in the rare-earth alloy thin film is 20–55 at%; the mass ratio of aluminum to silicon in the aluminum-silicon alloy foil is (75–98 wt%):(2–25 wt%). The aluminum-containing metal foil of this invention can improve the utilization efficiency of heavy rare earth elements, reduce the diffusion temperature, and shorten the diffusion time. The NdFeB diffusion magnet obtained by the preparation method of this invention significantly improves the coercivity of the magnet while reducing the decrease in remanence.

The application is suitable for the field of photovoltaic technology, and provides a boron diffusion device, a cell piece, a cell assembly and a solar cell production system. The boron diffusion device comprises a furnace body, the furnace body has a gas inlet and a gas outlet arranged oppositely in a first direction; a first air pipe has a first part pipe body extending into the furnace body; and a second air pipe has a second part pipe body extending into the furnace body, and the length of the second part pipe body is greater than that of the first part pipe body. The boron source gas in the furnace body can be uniformly diffused through the cooperation of the first air pipe and the second air pipe, so that the boron diffusion of the cell pieces at different positions in the furnace body is more uniform, and the uniformity of the sheet resistance of the cell pieces is improved.

The application discloses a rare earth slurry for grain boundary diffusion, a Nd-Fe-B diffusion magnet and a method. The rare earth slurry for grain boundary diffusion is prepared from raw materials including a rare earth powder, a heat-conducting powder, a binder and an organic solvent; wherein the rare earth elements in the rare earth powder include light rare earth and / or heavy rare earth; the heat-conducting powder is selected from one of aluminum nitride, silicon carbide and silicon nitride; the weight of the heat-conducting powder is 3-10% of the weight of the rare earth powder; and the particle size of the heat-conducting powder is 15-40 times of the particle size of the rare earth powder. The rare earth slurry for grain boundary diffusion can improve the diffusion effect of a subsequent magnet and the utilization rate of rare earth.

This invention provides a boron diffusion precursor structure, a P-type passivated contact structure, and a method for preparing the same. The boron diffusion precursor structure includes a first silicon oxide layer, an intrinsic polycrystalline silicon layer, and a first boron source layer disposed on a silicon substrate. The thickness of the first silicon oxide layer is 1–3 nm, the thickness of the intrinsic polycrystalline silicon layer is 20–400 nm, and the first boron source layer is made of silicon oxide containing carbon, boron, and nitrogen. The carbon doping concentration of the first boron source layer is greater than 1 × 10⁻⁶. 20 cm ‑3 Boron doping concentration greater than 1×10 20 cm ‑3 The thickness of the first boron source layer is greater than or equal to 10 nm. This invention uses silicon oxide containing carbon and boron as the source layer, where boron diffusion is easily controlled. The intrinsic polycrystalline silicon layer acts as a barrier to diffusion, achieving buffered boron diffusion. Boron diffuses through the polycrystalline silicon layer into the silicon substrate, reducing boron enrichment in the interfacial nano-silicon oxide layer, reducing interfacial defects, which is beneficial for improving the passivation performance of the P-type TOPCon structure. Furthermore, it can reduce the thickness of the polycrystalline silicon layer and decrease parasitic absorption.

This invention discloses a method for fabricating and monitoring a battery monitoring chip for a boron diffusion process. The fabrication method includes: forming a boron diffusion layer and a borosilicate glass layer stacked outside the boron diffusion layer on the main surface of a substrate through a boron diffusion process; forming a diffusion barrier layer outside the borosilicate glass layer; doping the diffusion barrier layer with N-type dopant atoms to form a doped layer containing N-type dopant atoms; the N-type dopant atoms then enter the borosilicate glass layer, transforming the borosilicate glass layer into a first composite doped silicon glass layer containing boron atoms and N-type dopant atoms; and removing the doped layer and the first composite doped silicon glass layer. This fabrication method improves the consistency between the boron diffusion layer in the battery monitoring chip and the boron diffusion layer of the solar cell, thereby improving the accuracy and reliability of monitoring the boron diffusion process.