Gallium doping method of Czochralski silicon monocrystalline and doping device thereof

Abstract

The invention discloses a gallium doping device, comprising a flying ring (2), a ring-shaped fixed sleeve (3) and a hollow cone (4), wherein the flying ring (2) is made of high-purity quartz, the hollow cone (4) is made of high-purity monocrystalline silicon, the ring-shaped fixed sleeve (3) is connected with the hollow cone (14), one end of the flying ring (2) is connected with the ring-shaped fixed sleeve (3), the other end of the flying ring (2) is connected with a handle part (1), and the handle part (1) is provided with a groove (11) which is matched with a crystal seed chuck on a crystal seed rod. The invention also discloses a doping method of gallium of Czochralski silicon monocrystalline through the gallium doping device. The invention can effectively avoid the poor influence on crystal growing caused by the splash of silicon melt.

Description

technical field [0001] The invention relates to a method for doping a Czochralski silicon single crystal, in particular to a method for doping a gallium element suitable for a Czochralski silicon single crystal. Background technique [0002] At present, the P-type single crystal silicon materials used in the production of solar cells are mainly divided into two types: boron-doped and gallium-doped. For boron-doped Cz solar cells, when it is exposed to light, the performance of the battery will decay, that is, the phenomenon of light-induced attenuation. For gallium-doped solar cells, this light-induced attenuation is much smaller. Test data reported at home and abroad show that the attenuation efficiency of gallium-doped CZ solar cells is generally less than 1%, while the attenuation efficiency of boron-doped Cz solar cells is generally greater than 3%. [0003] However, because the segregation coefficient of gallium is too small and the evaporation coefficient is high, th...

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Problems solved by technology

[0008] Patent 200810053398.X "Production method of gallium-doped solar single crystal" uses a special doping device, and has high requirements for equipment; and when doping, gallium is easy to splash out of silicon melt during the falling process. When the silicon melt splashes onto the wall of the quartz crucible, it will stick to the crucible wall after cooling, and the cooled silicon material will remelt during the crystal growth process, and when it falls into the silicon melt, the risk of poor crystal growth will increase; Fluctuations of the surface, resulting in single crystals can not be arranged in order of atomic number, resulting in broken bracts and dislocations

Moreover, the splashed melt may damage the single crystal furnace

[0009] Patent ZL00122075.6 "Heavily Doped Method for Czochralski Silicon Single Crystal Growth" uses an umbrella-shaped dopant, which is one-time use, and the evaporation coefficient of gallium is high. Extended, if the gallium volatilizes too much and needs supplementary doping, an additional umbrella dopant is required, which will lead to higher costs, so the economic benefit is not good

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