METHOD OF MEASURING CRYSTAL DIAMETER IN GROWTH APPARATUS Russian patent published in 2005 - IPC

FIELD: crystal growing.

SUBSTANCE: subject of invention is measuring crystal diameter and melt level in crystal-formation zone using two measuring devices mounted under different angles to vertical in vertical plane, which crosses melt surfaces. Further, two two-dimensional images are formed between crystal and melt and coordinates of at least one pair of coupled points belonging to different images but being projections of the same boundary point in image plains are measured. Coordinates of coupled points are used to calculate level of melt and coordinates of other points of boundary image on at least one image are determined. Using calculated value of melt level, these coordinates are transformed to obtain coordinates of boundary points in coordinate system of horizontal plane passing through boundary in measured point of melt level. From thus obtained coordinates of boundary points in above-mentioned coordinate system, crystal diameter is calculated. When averaging current crystal diameter values obtained in the course of rotation of the crystal around its axis, average crystal diameter is found. Advantage of invention consists in that measurements of melt level and crystal diameter are possible at considerable deviations of crystal axis during growth.

EFFECT: eliminated inaccuracy of crystal diameter measurement caused by shifted crystal axis and increased reliability of total measurement system including melt level and crystal diameter measurements.

3 dwg