Analysis of the traveling heater method for the growth of cadmium telluride

Abstract

We discuss the development and implementation of a comprehensive mathematical model for the traveling heater method (THM) that is formulated to realistically represent the interactions of heat and species transport, fluid flow, and interfacial dissolution and growth under conditions of local thermodynamic equilibrium and steady-state growth. We examine the complicated interactions among zone geometry, continuum transport, phase change, and fluid flow driven by buoyancy. Of particular interest and importance is the formation of flow structures in the liquid zone of the THM that arise from the same physical mechanism as lee waves in atmospheric flows and demonstrate the same characteristic Brunt-Väisälä scaling. We show that flow stagnation and reversal associated with lee-wave formation are responsible for the accumulation of tellurium and supercooled liquid near the growth interface, even when the lee-wave vortex is not readily apparent in the overall flow structure. The supercooled fluid is posited to result in morphological instability at growth rates far below the limit predicted by the classical criterion by Tiller et al. for constitutional supercooling.

A review on single crystal and thin film Si–Ge alloy: growth and applications

“…This process resembles that of zone levelling, where through a dilute solution, the recrystallization of a concentrated solution occurs and is usually performed vertically with a single pass of the liquefied zone. 102 The schematic and the principle of the technique is shown in Fig. 12.…”

Analysis of Te Inclusion Striations in (Cd,Zn)Te Crystals Grown by Traveling Heater Method

“…Three CZT ingots were grown using THM from a Te-rich solution under terrestrial conditions. The setup and growth process of THM growth of CdTe and CZT crystals has been discussed in detail in earlier studies [3,27,43]. The feeds were polycrystalline and had a composition of Cd 0.9 Zn 0.1 Te with a purity of 99.9999%.…”

“…Long-term CdTe and CZT growth experiments have been carried out in a close collaboration between European and Russian scientists using the FOTON and FOTON-M satellites with the Zona-4 and Polizon-2 facilities [13,[27][28][29][30][31][32][33][34]. These FOTON missions have aimed to grow high-quality crystals and investigate the origin of compositional inhomogeneities and defects in the grown crystals.…”

Cadmium telluride semiconductor detector for improved spatial and energy resolution radioisotopic imaging

“…[ 13 45 46 48 49 50 51 ] Traveling heater method (THM) constructed the best spectrometric class of polycrystalline detectors. [ 52 ] It could be reduced hole trapping, but two main drawbacks including a small size detector and high leakage current restricted its employment field. [ 10 ] Another technique is vertical Bridgman method that creates large volume and area of the detector and deduces the hole trapping.…”