10 results about "Oxygen precipitates" patented technology

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.

Methods for detecting oxygen precipitation induced defects during a polishing sequence. The methods are suited for detecting oxygen precipitates in heavily doped boron single crystal silicon wafers or in lightly doped wafers that are COP-free. The methods may involve inspecting a silicon wafer for LLS defects after a thermal anneal followed by a polishing sequence.

The application discloses a chain type pretreatment and efficiency improving equipment for TOPCon cell raw material silicon wafers. The equipment has a heating cavity with a silicon wafer conveying roller, and a temperature sensor and gas inlet and outlet pipelines are arranged in the heating cavity; heating, gas circulation and alarm functions of a central computer control device are provided. The core of the equipment is that the high temperature set in the furnace cavity can be reached, and the stability and uniformity of the temperature in the cavity are ensured; through the high temperature above 1100 DEG C and the oxygen atmosphere, the oxygen precipitation and vacancy defects in the photovoltaic N-type silicon are ablated and repaired, the recombination center in the material body is reduced, the bulk lifetime of the silicon is increased, and thus the cell efficiency is improved; the time required for pretreatment is greatly shortened, and the equipment is favorable for large-scale industrial application.

Methods for detecting oxygen precipitation induced defects during a polishing sequence. The methods are suited for detecting oxygen precipitates in heavily doped boron single crystal silicon wafers or in lightly doped wafers that are COP-free. The methods may involve inspecting a silicon wafer for LLS defects after a thermal anneal followed by a polishing sequence.

The invention relates to the technical field of semiconductor materials, in particular to a heavily-doped silicon single crystal oxygen precipitation detection method which comprises the following steps: S1, pickling a complete silicon wafer; s2, spraying the atomized transition metal salt solution on the surface of the silicon wafer; s3, placing the silicon wafer in a nitrogen atmosphere of 750-900 DEG C, and keeping the temperature constant for 30-60 minutes; s4, cooling the silicon wafer to room temperature at a cooling rate of 10-20 DEG C / s; s5, removing an interference layer on the surface of the silicon wafer; s6, observing the metal decoration pattern on the surface of the silicon wafer to judge the oxygen precipitation concentration; thus, through cooperative control of the temperature and the cooling rate, the metal ions are selectively deposited only at the oxygen precipitation and the induced defects of the oxygen precipitation, so that the concentration of the oxygen precipitation is accurately and reliably revealed; meanwhile, the oxygen precipitation concentration is measured by performing metal decoration on the surface of the complete silicon wafer, so that the influence of artificial damage caused by cutting the sample on the detection result can be avoided, and the accuracy of the oxygen precipitation concentration detection result is remarkably improved.

The invention relates to an efficient gettering method for a heterojunction solar cell and a silicon wafer, and belongs to the technical field of silicon wafer manufacturing, and the method comprises the following steps: S1, adding a carbon dopant into a polycrystalline silicon raw material, and growing a high-carbon-concentration monocrystalline silicon rod by using a czochralski method; s2, cutting the monocrystalline silicon rod in the step S1 to obtain a silicon wafer; and S3, carrying out phosphorus diffusion gettering treatment on the silicon wafer in the step S2 at the set temperature and time. According to the gettering method, the size of the original oxygen precipitate of the grown silicon wafer is reduced, the inner gettering capacity of the oxygen precipitate is weakened, metal impurities in the silicon wafer are more effectively removed through outer gettering, the minority carrier lifetime of the silicon wafer is prolonged, and therefore the battery efficiency is improved.

The application relates to the technical field of semiconductor material manufacturing, and discloses an N-type monocrystalline silicon wafer diffusion impurity absorption optimization method, which comprises the following steps: removing surface contaminants and tiny defects by pretreating an N-type monocrystalline silicon wafer; forming an impurity absorption layer on at least one surface of the pretreated N-type monocrystalline silicon wafer; performing diffusion annealing treatment on the N-type monocrystalline silicon wafer with the formed impurity absorption layer, and removing the impurity absorption layer material on the N-type monocrystalline silicon wafer after the diffusion annealing treatment; and completing the N-type monocrystalline silicon wafer diffusion impurity absorption optimization work. The impurity absorption layer formed on the surface of the silicon wafer can effectively capture and fix heavy metal impurities and defects, such as oxygen precipitation and metal precipitation, which may be generated in the subsequent process of the silicon wafer, so as to prevent the impurities and defects from causing adverse effects on the performance of the silicon wafer. The diffusion annealing treatment further promotes the diffusion of the impurities and the impurity absorption capacity of the impurity absorption layer, and ensures the effective removal of the impurities.

The invention discloses an interstitial oxygen content detection method for a heavily-doped silicon single crystal, which comprises the following steps: carrying out heat treatment at a target temperature on a heavily-doped silicon single crystal to be detected and a reference sample in an inert gas atmosphere, interstitial oxygen in the heavily doped silicon single crystal to be detected is converted into oxygen precipitation; respectively carrying out infrared spectrum measurement on the to-be-measured heavily-doped silicon single crystal and the reference sample which are subjected to heat treatment to obtain first infrared spectrum data of the heavily-doped silicon single crystal and second infrared spectrum data of the reference sample; performing differential processing on the first infrared spectrum data and the second infrared spectrum data; and determining the interstitial oxygen content corresponding to the characteristic absorption peak intensity from a preset standard model. Therefore, the measurement accuracy of the interstitial oxygen content is improved.

The invention relates to an in-situ heat treatment method of a monocrystalline silicon crystal bar. The in-situ heat treatment method of the monocrystalline silicon crystal bar comprises the following steps: providing a monocrystalline silicon crystal bar which finishes growing, wherein the monocrystalline silicon crystal bar is positioned in a single crystal furnace; the rotating speed of the monocrystalline silicon crystal bar is adjusted to a first rotating speed, the power of the main heater is adjusted, the temperature of the monocrystalline silicon crystal bar is kept within the temperature range of 650-950 DEG C for a preset time, and the first rotating speed is lower than the rotating speed in the growth process of the monocrystalline silicon crystal bar; the rotating speed of the monocrystalline silicon crystal bar is adjusted to a second rotating speed, the monocrystalline silicon crystal bar is pulled upwards, the temperature of the monocrystalline silicon crystal bar is reduced to 650 DEG C, and the second rotating speed is larger than the first rotating speed. By controlling the heat preservation time of the monocrystalline silicon crystal bar within the temperature range of 650-950 DEG C and the cooling rate within the temperature range of 650-950 DEG C, accurate regulation and control of the size and density of the oxygen precipitated phase are realized.

The application provides a carrier device and a heat treatment device for a heat treatment chamber, comprising: a carrier vehicle, the carrier vehicle comprising a base and wheels, the wheels being connected to the base and located below the base; a support seat, the support seat being arranged on the base and used for placing a semiconductor workpiece; a partition plate, the partition plate being arranged on the base and being perpendicular to the running direction of the carrier vehicle and used for partitioning the heat treatment chamber; and a rotary drive, the rotary drive being arranged below the base and connected to the support seat to drive the support seat to rotate about the axis thereof. The carrier device of the application comprises the carrier vehicle, the support seat, the partition plate and the rotary drive, when the carrier device carries a crystal bar through the heat treatment chamber, the partition plate is used for partitioning the heat treatment chamber, and the rotary drive drives the support seat to rotate so that the crystal bar is uniformly heated, the crystal bar is less likely to be polluted and deformed due to the small contact area and uniform heating, the number and size of oxygen precipitates are regulated, and the performance of the device is improved.