The effect of oxygen on the temperature fluctuation of Marangoni convection in a molten silicon bridge

Temperature fluctuations in a half-zone liquid bridge of molten silicon wer e measured under precisely controlled oxygen partial pressure in the ambien t atmosphere. A transition from a mode with non-periodic fluctuations in te mperature to one with periodic fluctuations occurred when the oxygen partia l pressure at the inlet was increased from 3.5 x 10(-7) to 1.8 x 10(-5) MPa . The transition indicates that the absolute temperature coefficient of sur face tension decreases with increasing oxygen partial pressure at the silic on surface. (C) 2001 Published by Elsevier Science B.V.