Fabrication of large-sized TaC-coated carbon crucibles for the low-cost sublimation growth of large-diameter bulk SiC crystals

Abstract

Low-cost TaC-coated graphite components (SinTaC) fabricated via wet powder forming and sintering has been proposed to reduce the production cost and improve the crystal quality of SiC wafers. However, the sizes of the SinTaC components are limited by the available sizes of graphite materials with coefficients of thermal expansion (CTEs) that match that of the TaC layer, hindering their application in the production of large-diameter SiC wafers. Here we demonstrate the scaling up of the sizes of SinTaC components through the reselection of new graphite materials based on available maximum size and CTE. The large-sized SinTaC components fabricated from the optimal reselected graphite material were tested in the growth of SiC via sublimation. The results confirm the enhanced durability of the large-sized SinTaC components compared to the graphite ones. Furthermore, the SinTaC components are reusable in multiple growth cycles.