“Crystallization E.M.F.” Investigation in the lithium niobate pulling process from the melt

E.M.F. in the lithium niobate crystal-melt system as a function of pulling and rotation rates, crystal diameter and orientation was determined. Total E.M.F. is a sum of thermo-E.M.F. and “crystallization E.M.F.” Δφ. The logarithmic approximation Δφ = Δφ₀ In (1 + /v₀), where v is a growth rate, Δφ₀ = 3.9 mV, v₀ = 1.9 mm/h is adequate. The Δφ magnitude is independent within the experimental error on the rotation rate and crystal orientation, whereas it is slightly increasing along with the diameter increase. Some existing models of electric phenomena accompanying crystal growth are discussed and a new model based on charge carrier injection into solid during growth is proposed.