Kyma Technologies Inc of Raleigh, NC, USA, has made a breakthrough on a 10-inch diameter AlN-on-sapphire template using its patented plasma vapor deposition of nanocolumns (PVDNC) technology.
The PVDNC AlN templates are chosen by manufacturers of blue, green and white LEDs as a replacement for bare and patterned sapphire substrates.
The 250mm (10-inch) sapphire substrate was provided by Monocrystal Inc of Stavropol, Russia, which provides sapphire products and metallization pastes to the semiconductor, optical, and photovoltaic industries.
According to Kyma, until recently, the wafer diameter standard for GaN LED wafer manufacturing has been 50mm (2”). Recently, sapphire manufacturers have made much progress in increasing the size of sapphire boules from which ever larger sapphire substrates can be sliced, with sapphire diameter demonstrations up to 12” being achieved by certain sapphire providers. This has enabled some of the major GaN LED makers to begin transitioning to larger-diameter sapphire - up to 150mm (6-inch) in some cases - to enhance manufacturing throughput and to achieve better economies of scale. While 10-inch sapphire based AlN templates are currently simply a demonstration, Kyma believes that the LED community will begin looking beyond 150mm (6-inch) diameter in the next few years.