Automated pulling of large alkali halide single crystals

Automated growing of large single crystals controlled by melt level sensor

“…It was, in particular, reported (GORILETSKY et al 1981) that if the ; i t value is linearly varied in time a t u p = const, the upper part of the crystal has a paraboloidof-revolution shape (i. e. the radial broadening rate decreases with t'he increase of growing crystal diameter). I n the presence of the directed flow of overheated melt a steady radial growth is achieved without &/up progranin2ing; in this case the value of this ratio corresponding to the crystal final diameter is established a t the very beginning of growth from the seed.…”

“…The method developed by the authors ( GORILETSKY et al 1981) facilitates the creation of the required radial temperature gradient using the same means because the crystal broadening can be affected by lowering the bottom heater temperature. I n this case the side heater temperature remains constant or even rises.…”

Scintillators: Crystal Growth and Scintillator Performance

“…These developments were started in the 1970s and 1980s for semiconductors (Si, first of all) [32][33][34] and halide crystal growth [35]. Some of these developments solved the problem of continuous growth of columnar structure rods [33], some allowed not only to sustain permanent feeding, but produced an extra purification effect [32], but only two of them found practical application for scintillator growth [34,35].…”

“…Some of these developments solved the problem of continuous growth of columnar structure rods [33], some allowed not only to sustain permanent feeding, but produced an extra purification effect [32], but only two of them found practical application for scintillator growth [34,35]. Both techniques were based on the Kyropulos method with feeding by solid raw material (granules or powder) or previously melted raw materials.…”

“…Both techniques were based on the Kyropulos method with feeding by solid raw material (granules or powder) or previously melted raw materials. 3 Stockbarger technique with raw-material feeding system [30] Because of the seeming external simplicity of this continuous-growth method, methods of pulling the crystal on the seed by way of raw-material feeding were widely adopted in practice [29, [35][36][37][38][39]. Figure 12.5 presents the principle of automated crystal-growth technology with a powder-feeding system [29, 35,36].…”