Research Progress on the Preparation and Thermal Conductivity Properties of Hexagonal and Cubic Boron Nitride

Author of the article:WU Cheng1,2, WANG Yan1,2, LI Jianfu1,2, ZHU Zhaojie1,2, YOU Zhenyu1,2, TU Chaoyang1,2

Author's Workplace：1. Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China; 2. Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China, Fuzhou 350108, China

Key Words：hexagonal boron nitride; cubic boron nitride; crystal growth; film; thermal conductivity

Abstract：With the development of microelectronic technology, the integrated circuits of electronic chips have become increasingly compact. The internal heat flux density is rising while the performance is improved, which puts forwards higher requirements for the heat dissipation capacity of electronic devices. The performance and efficiency of electronic equipment are severely restricted by low-heat-dissipation materials. Effective heat transfer and heat management have become important guarantees for the stable operation of next-generation microprocessors, integrated circuits, light-emitting diodes, etc. Therefore, there is an urgent need to explore novel semiconductor materials with higher thermal conductivity to extend the life of electronic devices. In recent years, hexagonal boron nitride (h-BN) and cubic boron nitride (c-BN) have attracted great attention. h-BN has a layered crystal structure similar to graphite, commonly known as “white graphite”, with excellent heat dissipation and insulation performance. While c-BN has a sphalerite structure similar to diamond, it has thermal conductivity second to that of diamond, which has the largest bandgap width among the third generation of semiconductor materials. Studies on h-BN and c-BN show that they both have good thermal conductivity and are expected to be a new generation of heat dissipation materials for electronic chips, which has become one of the research hotspots in the fields of thermal management. In this article, the research progress of the preparation methods of h-BN films and c-BN single crystals is reviewed, as well as their thermal conductivity properties, and the challenges and development prospects are also put forwards.