Growth and analysis of low-resistivity polycrystalline SiC using PVT method

Abstract

This study successfully achieved the growth of heavily nitrogen-doped polycrystalline silicon carbide (poly-SiC) crystals via physical vapor transport (PVT) method. Notably, poly-SiC crystals with low resistivity of 12 mΩ•cm were obtained through process optimization, demonstrating significant advancement in electrical performance. The systematic investigation focused on three critical aspects -growth temperature, chamber pressure, and post-growth wafer processing -with their synergistic effects on crystal quality comprehensively demonstrated through resistivity mapping, polytype characterization and growth rate analysis. Experimental results revealed that temperature predominantly governs the resistivity of nitrogen-doped poly-SiC through doping efficiency. By implementing a specially designed parameter decoupling strategy involving orthogonal experimental arrays and furnace structural modifications, we effectively resolved the complex inter-dependencies among temperature and pressure. By developing an advanced PVT method with low cost and easy control of growth conditions, low-resistivity poly-SiC wafers can be produced and processed as a material for wafer bonding application.