Thermal-stress reduction for a Czochralski grown single crystal

Thermal stress reduction for a Czochralski grown single crystal

In this paper an optimal control approach for thermal stress reduction inside a Czochralski grown single crystal is presented. Using the lateral heat flux as a control variable, an optimal control formulation for minimizing thermal stress with a given crystal shape is derived. Since thermal stress is also affected by the lateral shape of crystals during growth, the level of the stress can be re...

Luminescence and scintillation characterization of Silver doped KCl single crystal grown by Czochralski technique for photonic applications

In this study, the scintillation and optical properties of pure and silver doped potassium chloride (KCl:Ag) single crystals were reported. Pure and doped KCl bulk single crystals with a good optical quality and free from cracks were grown from the melt using Czochralski technique. Different analysis methods were used to study the optical and scintillation properties of the grown crystals. The ...

Thermal and Electrical Conduction of Single-crystal Bi2Te3 Nanostructures grown using a one step process.

Single-crystal Bi2Te3 nanowires (NWs) and nanoribbons (NRs) were synthesized by a vapor-liquid-solid (VLS) method from Bi2Te3 powder. To investigate the thermal properties of the Bi2Te3 nanostructure, a nondestructive technique based on temperature dependent Raman mapping was carried out. The Raman peaks were red shifted with increasing temperature. In addition, the fraction of the laser power ...

A Semianalytical Thermal Stress Model for the Czochralski Growth of Type III-V Compounds

In this paper we describe a semianalytical approach to computing the temperature and thermal stress inside a III-V compound grown with the Czochralski technique. An analysis of the growing conditions indicates that the crystal growth occurs on the conductive time scale. A perturbation method for the temperature field is developed for an arbitrary crystal profile using the Biot number as a (smal...

Thermal deactivation of lifetime- limiting grown-in point defects in n-type Czochralski silicon wafers