Numerical method for reducing stress level in GaAs crystals

3D computations of melt convection and crystallization front geometry during VCz GaAs growth

“…It is remarkable that the simplest model without convective effects and with opaque encapsulant provides the best agreement with experimentally obtained interface geometry. However, it is well known that both convective effects [2,3,6] and radiative heat transfer through the encapsulant [4,5] are important physical mechanisms affecting the crystallization process. So, it would be proposed that the agreement between the particular experiment and the particular data by the effective conductivity model is more accidental than general.…”

“…Additionally, the presence of encapsulant in the reactor hot zone complicates numerical analysis due to the conjugated flows of two immiscible liquids with heat and momentum exchange. There are indications in the literature that semitransparent properties of the encapsulant are of influence on heat exchange near the melt-crystal region and should be therefore taken into account [4,5]. Recently, 3D unsteady calculations within the direct numerical simulation (DNS) approach [3] and using large eddy simulation (LES) [6,7] have been applied for analysis of melt convection during 3 00 GaAs single crystal growth in the LPA Mark 3, a commercial system modified for the VCz technique.…”

The use of Langmuir–Blodgett films as recording layers in optical information carriers

“…These calculations could predict fourfold symmetry of etch pit profiles on 001 pulled GaAs and a similar sixfold symmetry in 111 pulled InP crystals. Later Kobayashi and Iwaki [4], Duseaux [5], Lambropoulos [6], Schvezov et al [7], Meduoye et al [8,9], Motakef et al [10], Dupret et al [11], Bornside et al [12], Zou et al [13] and several others performed calculations using the methodology developed by Jordan et al Consideration of only the five most active slip systems is related to the fact that the plastic strain tensor has only five independent components (in view of the incompressibility constraint) and cannot be uniquely resolved along the twelve slip systems. One way to overcome this is to consider only the five most active slip systems.…”

“…(111) 5 [011] (111) 6 [101] (111) 7 [101] (111) 8 [110] (111) 9 [011] (111) 10 [101] (111) 11 [011] (111) 12 [110] (111) thermal stresses arising due to the thermal gradients in the crystal. These stresses are relieved through the plastic deformation of the crystal lattice by the mechanism of the movement and multiplication of dislocations, thus producing high dislocation densities in as-grown crystals.…”

Numerical investigation of FZ-growth of GaAs with encapsulant

“…A prediction of the thermal field and the location of the growing interface was obtained by a global numerical simulation based on a conductiondominated model [2,3]. Thomas et al extended the dynamic thermal-capillary model to simulate a lowpressure, liquid-encapsulant Czochralski system for the growth of GaAs [4].…”