Control of several parameters such as dew point in polysilicon production
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1: Main raw materials and auxiliary materials 1〕Pure SIHCL3: Fe≤ 10ppb, B≤ 0.03ppb, P≤ 0.1ppb, Al≤ 10ppb. Pure H2: Dew point ≤ -50°C, O2≤ 5ppm. 2〕Silicon core: Diameter of ￠7-8mm, effective length: 2.800 meters. N-type: Resistivity of 50–250 ohms; curvature: ≤3/1000. 3〕N2 gas: Contains ≥99.99% N2, O2 ≤5ppm; dew point: ≤-50°C. 4〕Pure water: Resistivity ≥10 ohms; Al≤ 4ppm, Cu≤ 0.8ppb, Ca≤ 4ppb, B≤ 0.3ppb, P≤ 0.5ppb. 5〕Graphite: Spectrally pure, of uniform density with a homogeneous internal structure and no voids; ash content ≤0.01%, specific resistivity ≤20 ohms. Compressive strength ≥900kg/cm2, apparent specific gravity ≥1.8g/Cm3; hardness of 45–80Kg/Cm2. After being processed into shape, it is soaked in water, boiled in pure water until neutralized, dried, and then calcined at high temperature before use
I’m not sure which polysilicon plant this control criterion applies to; it seems to have quite low requirements!
These are the specifications given to us by someone else who asked us to select a dew point meter for them; could the actual value in production be higher than this?
Hehe, there are so few parameters here; it would be better if they were more complete
Thanks for sharing! ! ! ! ! ! ! ! !
Thank you, I’ve learned a lot; I’ll keep learning*
B, P is also acceptable; the dew points of hydrogen and nitrogen are too low. For hydrogen, -60 degrees is ideal, while for nitrogen, the value should be adjusted according to the company’s specific requirements