Improving the edge quality of single-crystal diamond growth by a substrate holder – An analysis

Publication date: Available online 3 October 2019Source: Comptes Rendus PhysiqueAuthor(s): Bo Yang, Qiao Shen, Zhiyin Gan, Sheng LiuAbstractDuring the growth of a single-crystal diamond by MPCVD, polycrystalline diamonds are prone to grow in the edge regions. This substantially reduces the usable area of the grown diamond film. In addition, the inhomogeneous distribution of internal stress causes diamond to crack during continuous growth. In recent years, a series of experimental studies have been carried out to solve these problems and some achievements have been obtained. However, in order to understand fundamentally the growth mechanism of diamond, the relationship between growth quality and various influencing factors still needs to be quantitatively studied through integrated simulations and experiments. Electron number density and substrate temperature are important factors affecting diamond crystallization quality. In this paper, the growth conditions of the diamond were simulated and analyzed. Simulation results were compared with the experimental results. This evidences that the surface temperature distribution is relatively homogeneous, and that the significant electron number density gradient in the axial direction is the main reason for the formation of polycrystals in the edge regions. Therefore, substrate holders with different cavity depths were designed and the substrates grew in the same temperature range. The surface morphologies, crystalline qualities, and ...

Source: Comptes Rendus Physique - October 4, 2019 Category: Physics Source Type: research