Translucent has designed a proprietary GaN-on-Si wafer template that features embedded DBR mirrors and can be used for manufacturing cost-effective LEDs. The design and method utilized to fabricate these wafers will be discussed at the International Conference on Nitride Semiconductors (ICNS-9).
The company will provide technical data about manufacturing a 100-mm-diameter wafer that reveals high reflectivity when used with a rare-earth-oxide material fabricated on a silicon substrate. A GaN layer is deposited on the obtained structure in order to support nitride epitaxy for growing LED structures.
The rare earth oxide (REO) material system offers lattice engineering features that can be used to alleviate strain caused while growing GaN. REO materials can be used to incorporate highly reflective mirrors in silicon substrates. Prospective clients can use the new technology for the growth of LEDs on wafers of large-diameters.
The solution offered by the company ensures that the substrate need not be removed and handle wafers need not be used for the next processing step. Since larger wafer sizes are being increasingly used by the LED industry,a single-step epitaxial solution is anticipated to ensure low-cost scaling. LEDs can be evolved on top of the GaN-on-Si template using the Translucent’s embedded silicon solution and comes equipped with an embedded DBR mirror. A layer of patented Rare Earth Oxide (REO) is deposited atop this DBR mirror to enable successive elimination of the substrate and to enable GaN to cover the template.
Calculations prove that thin layers of lattice-matched REO material can exhibit a mirror reflectivity of 98% and above at a wavelength of 450 nm. The material was grown at the company’s facilities with the help of molecular beam epitaxy (MBE) reactors. This high-quality growth paves the way for the development of high-quality crystalline interfaces to produce large-diameter silicon wafers. With the development of the wafer template, the company widens its commercial opportunities for embedded mirror material. The company is working to enhance its embedded silicon mirror technology to launch 150 mm and 200 mm wafers commercially.
Source: http://www.translucentinc.com/