90 kg sapphire crystal. Credit: Thermal Technology.
I’ve touched on LEDs a couple of times in the last few days, and in doing that research I got the distinct impression that because of strong demand in the LED markets, companies that have a hand in making the sapphire substrates for LEDs are doing quite well, both financially and technically.
For example, Illinois-based Rubicon Technology announced a few weeks ago that it has begun making 12-inch wafers for LEDs. Echoing the history of how silicon-wafer size growth has been playing a role over the last two decades in driving down semiconductor chip prices, polished sapphire wafers have grown from the two-inch standard size, to then four-inch and eight-inch. Thus, the 12-inch wafer marks a substantial achievement.
Part of the trick of making larger wafers is forming the large boules of pure sapphire. Currently, the LED industry seems to be centered on boules in the 80–90 kg range, but Rubicon has demonstrated that it can produce a 200-kg crystal.
In a press release, company president and CEO Raja Parvez, Rubicon President and CEO brags, “Rubicon’s ability to affordably produce larger wafers, free of defects, is key to helping industries that make and use LEDs scale to the volumes necessary to support the growth needed in the general lighting and consumer electronics.[…] our customers can depend on us for uniform, particulate-free sapphire wafers as well as flat, stress-free wafers. High quality sapphire wafers help our customers produce high quality LED wafers at volumes supporting the LED supply chain.”
In 2010, Rubicon said it had inked a $71 million six-inch wafer deal with an unnamed “major LED chip manufacturer” that extends through 2011. No mention is made in the new announcement about who might be interested in buying the 12-inch wafers, but the company goes out of its way to mention that Philips Lumildes and Lextar Electronics are using the six-inch variety.
The transition to larger diameter wafers in LED production has started. Earlier in 2010, Rubicon announced that the company entered into a $71 million agreement with a major LED chip manufacturer for which Rubicon will provide six-inch polished substrates. Companies such as Philips Lumiled and Lextar Electronics have announced six-inch production of LED wafers built on sapphire.
The company describes itself as “a vertically-integrated manufacturer with capabilities in crystal growth, high precision core drilling, wafer slicing, surface lapping, large-diameter polishing and wafer cleaning processes. Demand seems strong (according to Bloomberg.com, Parvez last week said that wafer prices are up 30 percent compared to the previous quarter) and investors seem to like what they see in Rubicon: When the company released is quarterly report Feb. 18, Rubicon’s stock price jumped 20 percent.
Another example of the industry see doing well is Thermal Technology. Unlike the vertically integrated Rubicon, Thermal Technology focuses on making and selling “crystal growth equipment and high temperature furnace systems.” In other words, it sells the equipment so other companies can make the boules and then slice and prepare the sapphire wafers.
In early December 2010, Thermal Technology — a privately held company — announced it would begin marketing equipment to make 90 kg boules using a Kyropoulos growth method. The announcement must have struck a chord because is released another announcement Feb. 10, 2011, that trumpets that the company has already received 59 orders for the new crystal grower “from customers in Taiwan, Korea and China. In total, these growers will produce 5.2 million TIE (two-in-equivalents) per year.”
About 10 seconds into this recent video, you can see Sino-America Silicon Products, one of the company’s LED-producing customers in Taiwan, celebrate the creation of one of the 90 kg crystal grown with the Thermal Technology system
Matt Mede, Thermal Technology’s president and CEO, seems pleased. He says in a press release, “Previously, the Russian growers were the industry standard. The superiority of our design, crystal size and tool capability are quickly making Thermal Technology the industry leader in this market sector,” Mede continues.