Suntech’s black silicon solar cells enter mass production

Work on the Chinese manufacturer’s black silicon solar cells began last June. It now says they have entered into mass production, with an annual capacity of 500 MW expected by this Q1.

“Suntech's R&D team has effectively fixed all the issues related to diamond wire sawing of multi-crystalline silicon wafers in mass production with self-developed metal assisted chemical etching,” says the company in a statement released.

It adds, “Through optimized nanostructured processing technology, an additional absolute efficiency gain up to 0.3% has been achieved comparing with additive direct texturing.”

No other details were available and Suntech could not be immediately reached for comment.

Black is the new black

With the growth of diamond wire sawing, black silicon’s popularity has soared recently. In the November 2017 print edition of pv magazine, editor Mark Hutchins examined the technology’s potential to bring about a resurgence in multicrystalline silicon.

Several tier-1 manufacturers are operating gigawatt-scale capacities, and process and equipment suppliers have reported strong interest in the technology.

Natcore, a U.S.-based company that holds the license for a black silicon process originally developed by the U.S. National Renewable Energy Laboratory (NREL), says its main interest lies in the technology’s anti-reflective properties.

However, it is the texturing function of black silicon, and its potential as a solution to enable diamond wire sawing in multicrystalline wafer production, which seems to have played the largest role in its recent popularity.

Another Chinese giant, Canadian Solar, has become the first company to turn all of its multi cell capacity (more than 4 GW) over to black silicon. “In industrial production, we have been able to achieve 19% average efficiency,” Xusheng Wang, Senior Director of Technical Integration at Canadian Solar told Hutchins.

GCL Systems Integration (GCL SI), is also putting faith into black silicon processes, having announced the achievement of 20.78% peak cell efficiency using the technology, at the recent EU PVSEC conference held in Amsterdam.

Both of the manufacturers said black silicon processes are cost effective and can easily be added to existing production capacities.

“Black silicon deals with front side texturing and has no conflicts with other technologies like diffusion, passivation, or metallization,” explains Wang.  “What’s more, black silicon can be used with PERC, which makes multi-PERC much more compatible in comparison with mono-PERC.”

It will have to compete, though, with other technologies which allow diamond wire sawing for multicrystalline wafers.

Read the full Black Silicon article.