APPEARANCE OF A BAROCLINIC WAVE IN CZOCHRALSKI SILICON MELT

Temperature fluctuations of a Si melt in a Czochralski crucible are measured. Spectral analysis revealed that a baroclinic wave occurred above a certain crucible rotation rate. Above the critical condition, the temperature fluctuation increased abruptly in amplitude. The fluctuation involved a characteristic frequency component that did not coincide with the period of the crucible rotation. Examination of phase differences among the data measured at different point revealed that the periodic motions were the result of azimuthal propagation of a temperature pattern. Experimental conditions based on the thermal Rossby number yielded wave motion which agrees with the theoretical value according to the theory of baroclinic instability.