Fotoenergetikada nanostrukturali yarimo‘tkazgich materiallar II xalqaro ilmiy anjumani

Fotoenergetikada nanostrukturali yarimo‘tkazgich materiallar

II xalqaro ilmiy anjumani 
 
19-20 noyabr 2021 yil 
34 
‒ Me-grade silicon treatment by HCl for obtaining of trichlorosilane (SiHCl
3
) 
or to a lesser extent monosilane (SiH
4
), followed by purification of these 
substances from impurities; 
‒ hydrogen recovery of trichlorosilane or pyrolysis of monosilane to obtain 
semicrystalline silicon ingots ‒ raw or silicon granules of semiconductor purity; 
‒ metallurgical obtaining of ingots and granules Si from the melt by 
Bridgeman, Czochralsky or Stepanov method in monocrystalline or large-grain 
polycrystalline form with the provision following special doping (usually acceptor) 
to ensure the resistivity of these materials ~1 Ohm∙cm.; 
‒ cutting of ingots to the plates; 
‒ operations of creating solar cells as itself that is the manufacturer of the pn-
junction, enlightening coating, contacts, as well as a number of operations aimed at 
increasing the efficiency of SC, such as the texturing of the front surface, the 
creation of built-in pulling electric fields, etc.; 
‒ obtaining materials for solar modules manufacturing (covering glass, 
aluminum frame, switching means, etc.) and the manufacture of modules; 
‒ production of reference devices for installing modules and their switching in 
solar panels , placement of panels on the ground and their switching in the solar 
arrays with the connection of the accumulators of electricity and special devices 
for its conversion to an alternating current of industrial frequency. 
Given the standards of the consumption of the feedstock and the average 
output of finished product fabrication on the operations of the manufacture of 
silicon actually suitable for the manufacture solar cells, one can see, that at the end 
of the twentieth century on the manufacture of solar cell with the installed power 
of one watt (at solar radiation 850 W/m2), ~10 g monocrystalline Si was spent 
(taking into account silicon losses when ingots cutting on plates and their chemical 
machining). 
To obtain this amount of monocrystalline silicon, it is necessary to produce 
~100 g of quartz or quartzites, to melt in the electric arc furnace at least 45 g of 
technical silicon, produce from this amount of technical silicon about ~150 g of 
trichlorosilane, to obtain by a hydrogen reduction ~15 g of pure silicon, and 
remake it into the desired 10 g of monocrystalline Si.
The introduction into industrial production at the beginning of the XX1 
century of modern reverse technologies for obtaining silicon of electronic purity 
has radically increased the environmental purity from this most dangerous 
technology stage with a simultaneous increasing in product output and reducing the 
cost of technical silicon.. 
This ultimately led almost to a multiple reduction in the cost of silicon and to 
the same, somewhat unexpected reduction in the price of solar electricity, because 
the proportion of silicon in the cost of solar cells didn't exceed 30 %.
These undoubted successes exacerbated the question of the need to modernize 
the process of electric arc melting of silicon from quartzite, which looks to be the 

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