Method and apparatus for controlling the growth process of a monocrystalline silicon ingot

摘要

The present invention provides a method and apparatus for controlling the growth of a silicon ingot in which the diameter of the growing silicon ingot can be accurately measured. A camera captures an image of the interface ring between the growing silicon ingot and the silicon melt. An image processor extracts local intensity maxima from the captured image, which are then digitized into an image data which comprises attributes of the pixels forming the local intensity maxima. An analyzer statistically analyzes the image data to derive parameters of an equation statistically simulating the interface ring. A probabilistic filter conducts the statistical analysis on the equation in which the respective pixels are weighted by their weight factors. The weight factor functions to attenuate the effect of noises caused by pixels which do not represent the interface ring. The statistical analysis may be repeated, using the renewed parameters, to progressively attenuate the effect of the noises to thereby obtain a satisfactorily accurate diameter of the silicon ingot.