[PDF]  https://doi.org/10.3952/physics.v61i3.4518

Open access article / Atviros prieigos straipsnis
Lith. J. Phys. 61, 183–190 (2021)
 

REDUCTION OF IMPURITY SOURCES IN Si CRYSTAL GROWTH SYSTEM WITH ELECTRON GUN BEAM HEATING
Anatoly Kravtsova, Janis Virbulisb, and Armands Krauzeb
  a KEPP EU, 5 Carnikavas Street, Riga, Latvia
b Institute of Numerical Modeling, University of Latvia, 3 Jelgavas Street, Riga, Latvia
Email: doc@keppeu.lv

Received 18 December 2020; revised 19 May 2021; accepted 21 May 2021

A new series of experiments was conducted to determine the source of impurities in the process of silicon crystal growth with electron beam heating. A gas-dynamic window was placed between the electron gun and growth chamber. Also positively-charged traps were placed along the crucible to reduce the number of electrons hitting the chamber and the crucible. Five experiments were conducted: two with the window, two with charge traps, and one with both the window and charge traps.
The analysis of obtained samples showed that the gas-dynamic window decreases the content of Al, Cu, Fe, Cr and O2, and the trap, used in the experiments, decreases the content of Fe, Cr and Cu in residues of the melt. The content of all impurities, except Al, is close to the goal level.
Al impurities come only from the gun, but the gas-dynamic window cannot eliminate them completely. It seems that Al impurities come either as neutral atoms carried by the gas or as positively charged ions. To reduce these impurities, a separation of the Al flow from the beam by the magnetic field is proposed.
Keywords: electron optics, materials testing and analysis, silicon, doping and ion implantation
PACS: 41.85.-p, 81.70.-q, 61.72.uf

PRIEMAIŠŲ ŠALTINIŲ MAŽINIMAS Si KRISTALŲ AUGINIMO SISTEMOJE SU KAITINANČIU ELEKTRONŲ PATRANKOS PLUOŠTU
Anatoly Kravtsova, Janis Virbulisb, Armands Krauzeb

a KEPP EU, Ryga, Latvija
b Latvijos universiteto Skaitmeninio modeliavimo institutas, Ryga, Latvija



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