20 March 2012

SiGen launches second-generation production equipment for thin kerf-free wafering

Wafering tool supplier Silicon Genesis Corp (SiGen) of San Jose, CA, USA, which was founded in 1997 to provide engineered substrate process technology for the semiconductor, display, optoelectronics and solar markets, has finalized the specifications of its second-generation production system.

As well as being used for fabricating thin-silicon solar wafers, SiGen’s core proton-beam-induced wafering technology is capable of supplying materials to other applications such as high-brightness (HB)-LEDs and packaging/3D structures using silicon, gallium arsenide (GaAs), germanium, silicon carbide (SiC), gallium nitride (GaN) and sapphire. The firm claims that the key advantage is minimizing the cost of high-performance materials while maintaining their effectiveness in demanding end-applications.

SiGen says that the system design is a result of over six years of development, prototype testing and solar cell material evaluation with numerous equipment and solar cell partners. The new GenII PolyMax system follows what are claimed to be industry firsts, including making free-standing 20μm, 50μm, 85μm, 120μm and 150μm of 125mm and 156mm industry-standard square kerf-free monocrystalline silicon solar-cell wafers (resulting in what was claimed to be the first true monocrystalline c-Si kerf-free wafering for the PV industry).

SiGen claims that the PolyMax high-volume manufacturing system brings the industry a step closer to replacing wire saw processes with lower-cost waste-free wafering. A strength of the system is its ability to produce wafers thinner than is achievable with wire saw technology, allowing the production of cells with higher conversion efficiencies and lower cost.

“The solar industry’s severe pricing pressure further strengthens the proton-beam-induced wafering approach,” believes president & CEO Francois Henley. “We first introduced our beam-induced cleaving technology at the 2008 PVSEC [Photovoltaic Science and Engineering Conference] with 50μm-thick wafers made using a prototype 2MeV high-energy proton implanter,” he adds. “The benefit of using our technology will significantly cut the cost of making high-efficiency solar cells, allowing the PV industry to reach unsubsidized grid parity years ahead of expectations,” he believes. “These thin and ultra-thin solar wafers have been well characterized and tested, both by our partners and independent third-party laboratories.”

Henley reckons that recent announcements from other thin-silicon technology providers confirm the need for new approaches and processes that can cut costs in making high-efficiency silicon absorbers. “We evaluated the Ampulse hot-wire CVD technology while it was still at NREL [National Renewable Energy Laboratory] in 2006 in combination with a SiGen layer-transferred single-crystal silicon layer. We opted for our direct high-energy beam-induced cleave approach instead. The approach has merit if the company can indeed make high-quality films using their novel textured backing technology,” Henley notes.

“We are also closely following recent announcements by Twin Creeks Technologies of a process similar to our beam-induced wafering, except it is reportedly limited to bonded (non-free-standing) 20μm films. As the pioneers of beam-induced wafering, and assuming it is not utilizing any of our technology embodied in our 100+ US patent portfolio which we are monitoring, SiGen is happy to see another company recognizing the importance of thin crystalline silicon for its capability to dramatically reduce the cost of solar cells,” he adds. “The fact that Twin Creeks Technologies was founded by a venture capital firm shortly after it evaluated SiGen’s beam-induced wafering business plan and technology, including our prototype 2MeV implanter, is of concern.”

See related items:

Twin Creeks launches system for producing ultra-thin Si, Ge, GaN, SiC and sapphire wafers

Tags: Thin-silicon solar wafers GaAs GaN SiC Substrates

Visit: www.sigen.com