The Experts below are selected from a list of 6852 Experts worldwide ranked by ideXlab platform
Hayder Alatabi - One of the best experts on this subject based on the ideXlab platform.
-
a Cooling Fin to enhance the efficiency of crystal growth by physical vapor transport
Materials Science and Engineering B-advanced Functional Solid-state Materials, 2019Co-Authors: Hayder Alatabi, Mohamad Ibrahim Cheikh, M H Hosni, J H EdgarAbstract:Abstract In general for crystal growth, material should deposit on the seed crystal and not on any adjacent supporting structures. This efficiently uses the source material and avoids the possibility of spurious polycrystals encroaching on, and interfering with the single crystal growth. In this paper, a new crucible design with a Cooling Fin in contact with the seed was simulated and experimentally demonstrated on the physical vapor transport (PVT) crystal growth of scandium nitride (ScN). The heat transfer of the growth cavity for a conventional crucible and a modified crucible with the Cooling Fin were modeled theoretically via computational fluid dynamics (CFD) with FLUENT. The CFD results showed that the seed in the modified crucible was approximately 10 °C cooler than the crucible lid, while in the conventional crucible the temperature of the seed and lid were uniform. The experimental results showed that increasing the temperature gradient between the source and the seed by employing the Cooling Fin led to a dramatic increase in the growth rate of ScN on the seed and reduced growth on the lid. The relative growth rates were 80% and 20% on the seed and lid respectively, in the modified crucible, compared to 25% and 75% with the conventional crucible. Thus, the modified crucible improved the process by increasing the growth rate of single crystals grown by sublimation.
J H Edgar - One of the best experts on this subject based on the ideXlab platform.
-
a Cooling Fin to enhance the efficiency of crystal growth by physical vapor transport
Materials Science and Engineering B-advanced Functional Solid-state Materials, 2019Co-Authors: Hayder Alatabi, Mohamad Ibrahim Cheikh, M H Hosni, J H EdgarAbstract:Abstract In general for crystal growth, material should deposit on the seed crystal and not on any adjacent supporting structures. This efficiently uses the source material and avoids the possibility of spurious polycrystals encroaching on, and interfering with the single crystal growth. In this paper, a new crucible design with a Cooling Fin in contact with the seed was simulated and experimentally demonstrated on the physical vapor transport (PVT) crystal growth of scandium nitride (ScN). The heat transfer of the growth cavity for a conventional crucible and a modified crucible with the Cooling Fin were modeled theoretically via computational fluid dynamics (CFD) with FLUENT. The CFD results showed that the seed in the modified crucible was approximately 10 °C cooler than the crucible lid, while in the conventional crucible the temperature of the seed and lid were uniform. The experimental results showed that increasing the temperature gradient between the source and the seed by employing the Cooling Fin led to a dramatic increase in the growth rate of ScN on the seed and reduced growth on the lid. The relative growth rates were 80% and 20% on the seed and lid respectively, in the modified crucible, compared to 25% and 75% with the conventional crucible. Thus, the modified crucible improved the process by increasing the growth rate of single crystals grown by sublimation.
Ching-yu Yang - One of the best experts on this subject based on the ideXlab platform.
-
design of a longitudinal Cooling Fin with minimum volume by a modified newton raphson method
Applied Thermal Engineering, 2016Co-Authors: Quan Nguyen, Ching-yu YangAbstract:Abstract In this paper, the minimal volume of nonlinear longitudinal Cooling Fin design problem by using a modified Newton–Raphson method is presented. The profile of the Fin is built by B-spline curve in which the control points of the B-spline curve are regarded as optimization variables. Additionally, a mechanism called “volume updating” is added into the modified Newton–Raphson algorithm to obtain the minimum volume of the Fin. Four cases with the different boundary conditions and thermal properties of the longitudinal Fin are presented to demonstrate the proposed method. The results show that the optimal Fin obtained by the proposed method is in good agreement with Schmidt's (1926) result and is better than that of Azarkish, et al. (2010). It is concluded that the B-spline with the second degree and three control points could be used enough to Find the minimum volume of the longitudinal Fin for the linear and nonlinear Fin design problems. From the results obtained in four cases, it appears that the proposed method is an efficient and accurate method in Finding the minimum volume of the nonlinear longitudinal Cooling Fin design problem.
Quan Nguyen - One of the best experts on this subject based on the ideXlab platform.
-
design of a longitudinal Cooling Fin with minimum volume by a modified newton raphson method
Applied Thermal Engineering, 2016Co-Authors: Quan Nguyen, Ching-yu YangAbstract:Abstract In this paper, the minimal volume of nonlinear longitudinal Cooling Fin design problem by using a modified Newton–Raphson method is presented. The profile of the Fin is built by B-spline curve in which the control points of the B-spline curve are regarded as optimization variables. Additionally, a mechanism called “volume updating” is added into the modified Newton–Raphson algorithm to obtain the minimum volume of the Fin. Four cases with the different boundary conditions and thermal properties of the longitudinal Fin are presented to demonstrate the proposed method. The results show that the optimal Fin obtained by the proposed method is in good agreement with Schmidt's (1926) result and is better than that of Azarkish, et al. (2010). It is concluded that the B-spline with the second degree and three control points could be used enough to Find the minimum volume of the longitudinal Fin for the linear and nonlinear Fin design problems. From the results obtained in four cases, it appears that the proposed method is an efficient and accurate method in Finding the minimum volume of the nonlinear longitudinal Cooling Fin design problem.
Mohamad Ibrahim Cheikh - One of the best experts on this subject based on the ideXlab platform.
-
a Cooling Fin to enhance the efficiency of crystal growth by physical vapor transport
Materials Science and Engineering B-advanced Functional Solid-state Materials, 2019Co-Authors: Hayder Alatabi, Mohamad Ibrahim Cheikh, M H Hosni, J H EdgarAbstract:Abstract In general for crystal growth, material should deposit on the seed crystal and not on any adjacent supporting structures. This efficiently uses the source material and avoids the possibility of spurious polycrystals encroaching on, and interfering with the single crystal growth. In this paper, a new crucible design with a Cooling Fin in contact with the seed was simulated and experimentally demonstrated on the physical vapor transport (PVT) crystal growth of scandium nitride (ScN). The heat transfer of the growth cavity for a conventional crucible and a modified crucible with the Cooling Fin were modeled theoretically via computational fluid dynamics (CFD) with FLUENT. The CFD results showed that the seed in the modified crucible was approximately 10 °C cooler than the crucible lid, while in the conventional crucible the temperature of the seed and lid were uniform. The experimental results showed that increasing the temperature gradient between the source and the seed by employing the Cooling Fin led to a dramatic increase in the growth rate of ScN on the seed and reduced growth on the lid. The relative growth rates were 80% and 20% on the seed and lid respectively, in the modified crucible, compared to 25% and 75% with the conventional crucible. Thus, the modified crucible improved the process by increasing the growth rate of single crystals grown by sublimation.