A Bright Blue Future

Radhika Dirks Uncategorized

Blue LEDs: little bright shiny sources of incoherent 405-nm photons. Back in 2004, if you happened to be a graduate student in nanotechnology, there were few things cooler than a blue LED.  When these started invading consumer electronics, even the poorest of consumers (= graduate students) started upgrading to quality toasters just because the new toasters had 3 of these awesome new lights. 3 blue LEDs!

Nowadays, LEDs illuminate almost every traffic light in the country. LEDs, which stand for Light Emitting Diodes, are cheap, extremely efficient, and last forever. But what (almost) singly handedly made them street smart was the exorbitant replacement costs of the incumbent – paying for service personnel to keep replacing fused light bulbs every two years or so. And this is key for any new technology – it is not sufficient to be better than status quo but key market drivers need to be in place for overwhelming success. Everyone knows indoor lighting is the next big market for LEDS, roughly $100 billion big. Quite a few startups, e.g., Bridgelux, Switch Bulb, Lemnis lighting, as well as giants, like Philips, Nichia, feature actively in this space. But who will win this commercial indoor-lighting LED war? And are there key market drivers in place?

Which LED startup will dominate indoor lighting?

My bet is on Shuji Nakamura’s startup Soraa Inc. Nakamurua rose to the fame as the inventor of two of the coolest technologies that made grown men squeal like little girls back in 2004– the blue led and the technology that made BLUE LEDs seem like a child’s toy – the blue laser. So what made us graduate students crazy about these blue lights? You see, it wasn’t just the color or the need to be made a statement with an untypical laser pointer. It was what the color signified: the underlying semiconductor technology. There was a new kid on the nano-block: InGaN, Indium Gallium Nitride. The fact that InGaN was then exiting peer-reviewed journals to enter Target signaled the collapse of one of the biggest bottlenecks typically found in new semiconductors: performance-limiting material defects. While the number of defects in InGaN has been decreasing drastically, InGaN  is still roughly three times more defective and more expensive than that of Silicon, a technology with a 5-decade lead time advantage.

Currently, most LED startups, e.g., Bridgelux, use cheaper Silicon (or other) substrates as a base for the InGaN ‘active’ layer. Nakamura’s Soraa Inc., launched in 2008, grows their LEDs on GaN substrates, a much more natural fit for InGaN, thereby eliminating ‘droop’, a phenomenon limiting efficiencies of LEDs. Sorraa has chosen performance over cost. A winning decision if there are enough market drivers to eventually drive down costs.

Are there enough market drivers  for Soraa to succeed?

Absolutely. Blue LEDs and their cousins, blue lasers, feature in Blue-Ray DVDs, Playstations, and displays, including LED TVs . In fact, ‘true’ Red, Blue, and Green LEDs are the holy grail of displays. Turns out 405-nm LEDs is not “truly” blue but violet. These appear blue because of the response sensitivity of human eyes and fluorescence from ambient light. Both true blue and true green LEDs made possible from InGaN nanostructures will be brighter and more efficient and can combine with true red to form the holy trinity of displays. And along with Playstation and Blue-Ray markets lead to winning InGaN plays! Sorraa can base its strategy on winning performance and count on a market-driven learning curve advantage.

Moreover, choosing materials based on current or past costs does not always lead to a winning strategy. Case in point: last year’s biggest cleantech failure, Solyndra. What makes performance over cost win? The presence of market drivers. Market drivers worked against Solyndra. Polysilicon, Solyndra’s material of choice increased in price, one of the key factors leading to their demise.

Here’s to blue LEDs and the hope of a brighter future! May Nakamura & Soraa succeed!