Silicon Investor (SI) -- The First Internet Community

STOCKTALK

We've detected that you're using an ad content blocking browser plug-in or feature. Ads provide a critical source of revenue to the continued operation of Silicon Investor. We ask that you disable ad blocking while on Silicon Investor in the best interests of our community. If you are not using an ad blocker but are still receiving this message, make sure your browser's tracking protection is set to the 'standard' level.

Technology Stocks : Energy Conversion Devices -- Ignore unavailable to you. Want to Upgrade?

To: Krowbar who wrote (8153)	2/7/2006 9:54:54 PM
From: alfranco	Respond to of 8393

Del, <Have I missed something, or has Ge combined with Si been mentioned before?> Yes it has been mentioned in this and Stan's earlier patent app for mobile substrates which you and I particularly discussed around Nov 2004. As you know, Germane gas is used to create the middle and bottom intrinsic layers of the triple junction cell using amorphous silicon combined with germanium (from silane and germane gas that is plasma deposited on the moving steel substrate in the current 25MW machina). Stan has been using Ge since the early 90s in Unisolar PV in an attempt to better capture the long wavelength (red) photons and raise overall efficiency. Here's a link to the much longer earlier patent app that this newer one is a followup to: appft1.uspto.gov where Stan also speaks of amorphous and microcrystalline Si or SiGe. All in all, I view both these patent apps as Stan "covering the waterfront" broadly for deposition and fabrication of a whole host of devices on a roll-to-roll machine not just PVs but display devices where polysilicon is key... because it is faster due to faster carrier mobility which Stan explains in the both patent apps. I personally don't think polysilicon is going to be the next step for Unisolar since it is a poor absorber of photons in 1-2 micron thicknesses but others can speak (mred, et al) as to such thin polySi layers suitability/desirability in emissive displays where I think it is applicable. I think Unisolar is first building clones with tweaked triple junction cell output to enable quick rampup and I would guess the next generation solar cells would be amorphous top layer/nanocrystalline bottom layer quite possibly without germane... but that's ahead a year or two or three<g> Al