A Method of Controlling the Consistency of Doping Curves

Abstract

The invention discloses a method for controlling the consistency of a doping curve, and belongs to the field of the photovoltaic technology. The method comprises the steps: boat entry, temperature increasing, oxidation, stepped deposition, temperature increasing and junction pushing, temperature decreasing and annealing, and boat leaving. The step of stepped deposition is a step of letting in nitrogen, oxygen and doping source gas for pre-deposition when there is temperature gradient from the tail of a furnace and the mouth of the furnace. The diffusion technology employs a method of stepped multiple deposition, improves the doping uniformity of a doping source on the surface of a silicon chip, enables the temperatures of all temperature regions to sequentially increase from the tail of the furnace and the mouth of the furnace through the design of the deposition step temperature, forms the temperature gradient, improves the solid solubility of the doping source in the region of the mouth of the furnace, solves a problem that the doping of the doping source in the region of the mouth of the furnace is excessively light, guarantees the consistency of surface concentration and the consistency of doping quantities of the doping sources of all regions, and guarantees the junction depth consistency of the silicon chip. The method enables the doping curve of the diffusion technology to be more consistent, is more consistent in electrical performance parameters, and improves the CTM of the assembly.

Description

technical field [0001] The invention relates to the field of photovoltaic technology, in particular to a method for controlling the consistency of doping curves. Background technique [0002] The existing diffusion process uses low-temperature deposition first, followed by high-temperature advancement, and adopts the method of furnace tail air intake and furnace mouth exhaust to make PN junctions. Due to the different temperatures of the high-temperature advancement steps, the furnace mouth temperature is high and the furnace tail temperature is low. The inconsistency of the temperature in each area of ​​the chip will easily cause the concentration of the doping source near the furnace tail to be high, and the concentration of the doping source at the furnace mouth to be low, resulting in the inconsistency of the PN junction depth. In addition, the temperature of the through-source deposition step is basically the same, and no temperature gradient is formed, which results in...

AI Technical Summary

Problems solved by technology

Due to the different doping levels, the curves after doping are inconsistent, resulting in significant differences in electrical performance parameters. After the final production of modules, the CTM value of the module is low. Among them, the CTM value, namely Cell ToModule, represents the output power of the module and the cell. The percentage of the total power is used to indicate the degree of power loss of the component. The higher the CTM value, the smaller the power loss of the component package. If the CTM value is low, the output power of the component may not meet the expected requirements. Complaints from customers, ultimately resulting in loss of economic benefits

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