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BluRay diode breakthrough

I'm just impressed to be seeing 1/2W singlemode. I wonder if they'll be able to develop similar technology to allow red and IR diodes to reach those power levels while remaining singlemode as well.
 





LarryDFW is trying to find 500mW red DVD diodes that are currently being manufactured and put in Drives. They are a flat plastic diode.
 
ElektroFreak said:
I'm just impressed to be seeing 1/2W singlemode. I wonder if they'll be able to develop similar technology to allow red and IR diodes to reach those power levels while remaining singlemode as well.
Click to expand...

Red diodes already have other things they do to the facets to lessen COD.

The AlON film is actually epitaxial here (which is actually really weird, Sharp's paper even expressed some surprise that it was epitaxial). So on the InGaN (and other films near the active region) it does some weird things that kindof change the bandgap at the facet (less absorption if the bandgap is higher than the wavelength of light) and kindof compensate surface states (dangling bonds at the edge can absorb light, so having fewer dangling bonds results in less light absorption).


For the AlInGaP red diodes, one of the things they already do it diffuse zinc into the facet of the diode, which actually disrupts the crystallinity of the lattice, kindof making the face of the semiconductor amorphous instead of crystalline. This makes a "window" (their words in papers, not mine) that helps with the surface states/dangling bonds at the edge of the semiconductor, lessens absorption, and therefore increases COD resistance.

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But then again, look at the behavior of red diodes vs. violet diodes. Violet diodes currently increase almost linearly with power, then die suddenly. That's COD, so helping the facets helps get to higher power. Red diodes though, they start to roll over in power with increasing current. That's not COD, that's heat, and improving facets won't help that at all. At this point, that may even just be a limitation of the material itself. Heat affects different materials very differently, and the nitride materials (violet diodes) have proven to be very resistant to heat relative to other materials systems.

So would a technology like this help with red diodes? Probably not with the current look of things...but I've been wrong before.
 
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Nice catch, pal !!! Thanks for sharing that with your Forum buddies, +1 REP. rob
 
maybe that guy who was building a blu-ray lightsaber out of a pipe can get his act together....
 
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