A combined carbon and oxygen segregation model for the LEC growth of SI GaAs

LEC- and VGF-growth of SI GaAs single crystals—recent developments and current issues

“…This clearly indicates that transport of reaction products in the fluid phases and/or reaction kinetics at phase boundaries cannot be neglected. Therefore, a transport model has been developed [28] which includes carbon and oxygen as control species according to the thermochemical model and system-releated parameters like area and thickness of the boron oxide layer acting as a diffusion barrier and its transport properties.…”

2D simulation of carbon transport at the growth of GaAS crystals by liquid encapsulated Czochralski techniques

“…The control of carbon concentration during vapor pressure-controlled Czochralski (VCz) growth [1], as well as during conventional LEC [2] growth of GaAs crystals, is of crucial importance for achieving the desired electrical crystal parameters. Today, the carbon concentration is commonly adjusted empirically by maintaining a certain CO partial pressure in the growth atmosphere [1,2].…”

“…Today, the carbon concentration is commonly adjusted empirically by maintaining a certain CO partial pressure in the growth atmosphere [1,2]. A critical point of this procedure is that it is difficult to transfer the parameters empirically found for a given experimental geometry to another, e.g., to different chamber, crystal, and crucible sizes.…”

“…A critical point of this procedure is that it is difficult to transfer the parameters empirically found for a given experimental geometry to another, e.g., to different chamber, crystal, and crucible sizes. Furthermore, the water content in the B 2 potential of boron oxide, influencing the carbon content in the melt, too. Simulation of the species transport is a way to analyze and understand better the relationship between the initial conditions and the dopand content in the crystal.…”

“…An attempt to describe the evolution of the carbon concentration during GaAs LEC growth was made in Ref. [2] by using a 1D model based on a non-conservative Scheil formulation extended by accounting for the carbon incorporation and extraction via CO transport through the encapsulant. The impurity transport was considered qualitatively by using average effective diffusivities.…”