SiC Single Crystal Semiconductors

This chapter is about the glittering jewel in the crown of SiC ceramics: the SiC single crystal semiconductor wafer, which took 50 years to develop and was first commercialised in 2001. SiC semiconductors have seen a rapid rise since 2001 because (1) threefold larger band gap than silicon; (2) 10-fold higher breakdown field strength than silicon; (3) threefold higher saturation drift velocity than silicon; (4) threefold higher thermal conductivity than silicon; (5) can operate at up to 600°C–650°C (silicon ~200°C). Thus SiC is superior to silicon on all key performance criteria, except for the price. Silicon currently dominates the global semiconductor market because it is a good cheap second best that has been around a long time, and semiconductor manufacturers are deeply invested in the expensive thermal management systems that silicon semiconductors require. Silicon will always remain the semiconductor of choice in low-temperature low-cost applications, but ultimately SiC will likely dominate the high-temperature, high-power applications. Already a $100 million PA market, SiC semiconductors are forecast to grow to $1 billion by 2032. SiC will ultimately dominate high-power semiconductor applications, notably. AC/DC, AC/AC and DC/DC power converters, which are central to so many contemporary applications, such as electric vehicles, renewable energy, and power transmission systems, are all rapidly growing markets. This chapter overviews the 50-year pathway, from 1954 to 2004, in developing high-quality SiC single crystal semiconductor wafer technology, examining the technical challenges, and the solutions developed. The chapter also explores the current SiC semiconductor market, the current applications, and the issues of relevance in growing the market for SiC semiconductor applications into the future.