Sapphire is used as the substrate in the production of large diameter silicon-on-sapphire (SoS) wafers that are used for the production of high performance radio frequency integrated circuits (RFICs). RFICs support a broad range of end markets including automotive, cellular handsets, communications infrastructure, consumer, industrial, military and space. Mobile devices such as smart phones and other devices benefit from SoS RFICs, compared to less efficient RFIC technologies, through reduced energy consumption, improved performance and smaller form factors.
SoS was invented 1963 at Boeing (then North American Aviation). But technical hurdles kept it from becoming a commercially viable technology until recently due to advances wireless communications in particular RF CMOS technology. RF CMOS is used in the wireless front-end circuits of mobile phones, 4G basestations and satellite systems. Some predict that RF CMOS will repace gallium arsenide (GaAs) and more recently gallium nitride for its cost, reliability and integration benefits.
According to Frost & Sullivan, the worldwide market for RFICs across the aerospace and defense, broadband, industrial, mobile wireless device, test and measurement equipment, and wireless infrastructure industries is expected to grow from $12.2 billion in 2010 to $29.2 billion in 2015, representing a CAGR of 19.1%.
For further reading on the ClearlySapphire.com Blog, LTE and the Benefits of Silicon-on-Sapphire.