Finite element method study on the temperature distribution in the cell of large single crystal diamond

Abstract

The temperature distribution in the cell of single crystal diamond grown by the temperature gradient method has been studied, which is based on the finite element method. Our results shwo that the temperature distribution in the synthetic process of single crystal diamond is not uniform. The highest temperature in the cell is located at the outside of single carbon solvent, and the lowest temperature in the cell is located near the diamond seed. The heat transfer and the mass transport have a same direction （from outside of carbon source to diamond seed）. The temperature gradient in the axial direction is higher than that in the radial direction, which explains why the size of synthetic single crystal diamond in the axial direction is larger than that in the radial direction. The model will be useful for the design of single crystal diamond grown by the temperature gradient method. Furthermore, this work will be hopeful to improve the cubic anvil type high pressure techniques for the synthesis of high quality diamond crystals.

Efficient thermal analysis method for large scale compound semiconductor integrated circuits based on heterojunction bipolar transistor

“…Many improved numerical methods for fast thermal analysis were developed, [21][22][23][24] in which compact heat transfer equations are solved to characterize the temperature distribution in all parts of the IC chip including the thick substrate based on partitioning an IC chip into many discrete three-dimensional (3D) elements. [25,26] The accuracy of the temperature distribution increases with the number of discrete 3D thermal elements increasing. In this case, the calculation would be significantly time-consuming, which makes it hardly possible to achieve a large scale circuit.…”