Rupert Goodwins' Diary

Wednesday 30/8/2006

By no coincidence whatsoever, "very shiny" is exactly how not to describe 70 percent of the blue laser diodes currently made by the Japanese. Blue laser diodes were invented late last century by Shuji Nakamura at Nichia Chemical Industries, who single-handedly engineered at least two revolutions in solid state light emitting devices. All those superbright blue LEDs around the place? They're his. Now, Nakamura's story is fascinating enough in its own right — he left Nichia amid complaints that he was still only getting a researcher's salary despite bringing in hundreds of millions of dollars in sales — but that hasn't stopped the blue laser diode getting refined and ready for production.

Unfortunately, the latest rumours, courtesy of Digitimes, are that the manufacturers of the lasers are only getting 30 percent yield from their factories, meaning most of the diodes they make aren't usable. With both HD-DVD and Blu-ray desperately gearing up to lock horns this Christmas — and the Sony PS3 completely dependent on the device — this is leaving a lot of people with looks of fear, doubt and apprehension. There aren't enough to go around, nor will there be until the first quarter of 2007.

I'm not sure how they can predict this. Yield goes up when it goes up — and you don't know that you've fixed the problems until that happens. When a semiconductor factory starts having problems, they can cascade into all sorts of interleaved issues: it can take a long time and a lot of money to iterate through all the various solutions you think you've found until you're back in the game.

Since none of the factories are doing very well, and they're all using the same licensed technologies, the problem would seem to be intrinsic with the process rather than local contamination or poor material control. Blue laser diodes are esoteric devices, using exotic materials treated in complex and non-standard ways; it's not just another run of a memory chip. I wouldn't put any money on things magically improving on schedule.

This is bad news for the HD-DVD and Blu-ray camps, but at least they're both in the same boat. Not so Sony, which is in the unenviable position of being severely limited in the production of PS3s while its rival is free to make hay while the gallium nitride doesn't shine.