WASHINGTON – Squeezing another penny out of the cost of conventional solar cell manufacturing is no longer a viable approach for cleantech companies that have seen the price of solar panels drop by more than 40 percent since 2011. Addressing that reality, a manufacturing equipment maker promises to shift the focus of solar and chip manufacturing with a wafer production machine that it claims can greatly reduce silicon and other substrate material costs.
Twin Creeks Technologies (San Jose, Calif.) also claims its ultra-thin manufacturing process is suited to advanced production of LEDs and CMOS image sensors.
Reducing the amount of silicon needed to make solar cells is critical, argues Siva Sivaram, a former Intel manager and CEO of Twin Creeks, since it represents most of the manufacturing cost. Moreover, current solar manufacturing processes use only the upper layers of a silicon wafer, and Sivaram estimates that 90 percent of substrate is not used in the manufacturing process.
Twin Creeks has leveraged a technique called proton-induced exfoliation (PIE) to build a machine that produces extremely thin, flexible wafers. The company is taking the wraps off of a third generation version of its Hyperion wafer production tool this week (March 13), a machine that is says it ready for production. The company’s goal is to use its manufacturing and wafer handling and processing tools to produce monocrystalline wafers less than 1/10th the thickness of conventional wafers currently used to make solar cells.
Such an advance could help reduce solar cell material costs to the point where devices based on ultra-thin wafers would offset much of the price decline seen in the solar panel market over the last 18 months. Twin Creeks claims it lower cell production costs by about 50 percent.
The company’s version of PIE technology uses a beam of hydrogen ions to lift a super-thin layer of silicon measuring as little as 20 microns off a wafer that serves as the basis of a solar cell. The company claims the Hyperion machine can produce wafers for solar cells at a cost of about 10 cents per watt. The current cost is about 85 cents per watt. “I don’t want to compete [in the solar market] in taking out the last penny of cost” using traditional manufacturing techniques, says Sivaram.
The third-generation Hyperion tool is a “platform-level technology,” Sivaram insists. “We are now in manufacturing,” and the company expects to begin shipping systems this year.
Other solar startups are taking different approaches to reducing materials cost by using thinner wafers. For example, 1366 Technologies makes thin wafers for solar cells from molten silicon. The company’s approach automates several manufacturing steps like crystallization furnaces, sawing stations and ingot handling. Another solar manufacturer, Astrowatt, claims it can produce 25-micron-thick wafers.
Along with solar photovoltaics, Twin Creeks also is touting its wafer tool for manufacturing concentrated photovoltaics, LEDs, power electronics, 3-D packaging and CMOS sensors. The Hyperion system also handles other semiconductor materials like gallium nitride and germanium.
For now, Siveram says Twin Creeks is targeting the growing Chinese solar manufacturing markets. Being able to add value in the manufacturing process “resonates with the Chinese,” he adds.