There is a company in Australia that is working with this technology,they are called Solar Systems Pty Ltd who are a fully owned subsiduary of Silex Systems , they are developing a triple junction cell on a virtual germanium substrate, they are looking at achieving 50% or better efficiency, the substrate they will be making these cells on is much cheaper than what Spectrolabs are using, this substrate was developed by a company called Translucent Inc in the US which is also owned by Silex, they also own Solar Systems Pty Ltd.
Solar Systems got a $2 mil grant from the Australian Solar Institute to develop these cells, there were a number of companies involved with theis new cell, Solar Systems being the lead together with Translucent Inc, IQE, and Spectrolabs as well.
The question comes to why there is no solar cell manufacturers picking up the technology and start building high efficiency solar cell. There might be more than just the story in the article. I am eager to learn more.
Triple junction cells have been made by Boeing's SpectroLab division ( CA ) for quite a few years and used in all recent spacecrafts e,g. Mars Rover. They deliver 35 to 43 % conversion efficiency as predicted in Sze's Semicondutor textbook. As the layers have to be deposited slowly by MBE the cells are more expensive ( 10x of Si xTal ). For terrestrial / commercial applications CPV ( e,g. with mirrors ) have been tried.
What, if any. is the original contribution of Inferior College of Technology in this decades old concept ? Or is this just the usual editorial bias of now UK owned EE Times ?