Kuepper presented the paper in Anchorage last year, its abstract is here.

In the electrical world, there are resistors and conductors; that is, materials which resist electrical current passing through, and materials which allow it. In between the two are semiconductors, materials which resist a bit but also conduct a bit.

Silicon is a semiconductor. When the light strikes it, a little bit of electricity starts up, but it finds it difficult to get anywhere. So you can't just get a big slab of silicon, put it in the sun, put copper wires on the corners and get lots of electricity. Instead you get a thin layer of silicon (thinner stuff resists less and conducts more) and you put conductors all over it.

Usually those conductors are printed by a photolithogtaphic process, a bit like it's done with computer chips. This is slow and expensive. Kuepper's inkjet method promises to make this quicker and cheaper.

The major thing of getting the silicon and making it pure would remain. It's just the final printing this makes easier.

The paper is available from here

I'm not convinced that this is something that developing countries will pick up... just because some academics think so.
It may however lower production costs if it lives up to the creators promises.