Electron backscatter diffraction analysis of a CZT growth tip from a vertical gradient freeze furnace

Investigation of crystal growth of 50 mm CZT using SiC pedestal and pBN crucible

“…The FF region does not appear to be polycrystalline in nature, as has been observed by other investigators using different pedestal geometries for the bulk growth of CZT [9][10][11][12]. However, near the conical-cylindrical transition, new grains do appear to nucleate.…”

Simulating Interface Growth and Defect Generation in CZT – Simulation State of the Art and Known Gaps

“…In the simulations, temperature gradients of 2.5 x 10 4 K/cm to 3.0 x 10 5 K/cm and growth rates of 10 -3 cm/s to 3.5 cm/s are considered. These growth conditions are few orders of magnitude higher than that (about 10 -6 cm/s) during CZT crystal growth in typical vertical gradient freeze (Bridgman) growths [3]. In addition, the interface microstructures, which are important for interface morphological instability and defect generation during crystal growth, are often neglected during dendrite growth modeling.…”

“…The CZT solid has low thermal conductivity, low critical resolved shear stress (CRSS), low stacking fault energies, and exhibits retrograde Te solubility on cooling [1,2]. It is cubic but exhibits strong melt growth anisotropy with growth instabilities in the <110> and <112> directions [3]. The solid is extremely soft at elevated temperatures with a CRSS of approximately 0.2 MPa at the CZT growth temperatures so that dislocations are almost unavoidable during growth [1,2].…”

“…Models of the "growth of CZT crystals at the melt-solid interface (or SLI), and correlating physical growth and post-growth conditions with generation and incorporation of defects into the solid CZT crystal 3 " must necessarily consider the following outcomes or realizations as output from a hypothetical model: 1. The model needs to consider solidification at the SLI where the solid fraction in the model increases with time and the liquid fraction decreases with time, i.e., the interface moves.…”