Reliance Backed NexWafe GmbH Announces Key Breakthrough In Wafer Process

NexWafe GmbH (NexWafe) has announced significant breakthroughs in its solar wafer manufacturing technology. The firm seeks to make ultra-thin, high-efficiency, monocrystalline, low-carbon footprint solar wafers with an energy footprint 40% lower than conventional wafer making.

The German company achieved cell efficiencies equivalent to Czochralski (CZ) wafers in a production environment, marking a major milestone. Additionally, NexWafe highlighted advancements in ultra-thin wafers for space applications, as well as promising data on next-generation tandem-junction cells, demonstrating the versatility and potential of its EpiNex® technology across multiple cutting-edge applications. NexWafe has positioned it’s eventual wafer manufacturing process as not only competitive on costs, but equally efficient vis a vis the dominant Chinese wafer makers, offering a technology option for solar manufacturers.  Reliance has been a key backer of the firm, leading with a $29 million investment back in 2021 in its series C fund raise.

EpiNex Matches Industry-Leading CZ Benchmarks

NexWafe claims that  its EpiNex solar wafers achieved 24.4% efficiency on a commercial M6 heterojunction (HJT) cell line, for the first time delivering performance parity with conventional CZ wafers. Modules made from both TopCon and HJT solar cells match or exceed the performance of CZ wafers.

According to the firm, these results validate that NexWafe’s direct gas-to-wafer process as a seamless drop-in replacement for conventional CZ wafers, while offering the potential for significant cost savings by reducing material waste, lowering energy consumption by 40% and eliminating the saw damage etch process step in cell production. While conventional CZ technology results in 50% material waste due to polysilicon losses, EpiNex reduces this waste to under 10%, primarily by eliminating wire saw kerf losses.

EpiNex technology is also well-positioned to meet the evolving demands of next-generation solar cells for space applications and tandem-junction cells. These applications require thinner wafers with enhanced thermal stability, precise flatness and superior material quality – capabilities that EpiNex is uniquely designed to provide.

Notably, the oxygen content of EpiNex wafers is 20 times lower than conventional CZ wafers. This enables thermal stability and helps improve cell performance under high-temperature conditions.

Space Applications

NexWafe used EpiNex wafers to develop ultra-thin 70μm cells to address the growing demand for solar cells to power low earth orbit satellites. These cells exhibit radiation performance comparable to conventional CZ PERC and provide a significant power-to-weight ratio advantage, making them ideal for space applications.

Tandem-Junction Cells

NexWafe also made significant strides in next-generation cell applications. In collaboration with Le Centre Suisse d’Electronique et de Microtechnique S.A. (CSEM), tandem perovskite 2-junction cells using NexWafe’s EpiNex wafers achieved 28.9% efficiency, demonstrating their potential for advanced solar technologies. With superior smoothness at nano-scale, EpiNex wafers provide the ideal platform for the next generation of low-cost, solution-processed tandem perovskite cells.

Wafer Supply Chain

Today, China controls 99% of the world’s one terawatt of conventional CZ and wafering capacity, creating significant supply chain vulnerabilities.

To compete, reshoring manufacturing will require ongoing gains in both cost and cell efficiency. NexWafe’s patented technology makes these goals possible. By reducing material waste and energy consumption, NexWafe shifts wafer manufacturing onto a new cost curve, along with higher performance.

“These latest results are transformative for photovoltaic wafer manufacturing. EpiNex has the potential to shake up the solar industry in a way similar to the historic shift from polycrystalline ingots to single-crystal silicon. Just as that transition led the entire industry to retool its processes, unlocking significant efficiency gains and paving the way for today’s high-performance solar technology, EpiNex will drive a similar transformation,” said Davor Sutija, CEO of NexWafe. “Our technology creates an opportunity for regionally based manufacturers to compete with China, enabling a leapfrog in performance and cost, while significantly reducing carbon footprint.”

Poised for Gigawatt-Scale Production

Looking ahead, NexWafe is advancing its ProCon 2.5 tool design, slated for completion by June 2025. This innovative system leverages advanced heating systems and inline atmospheric pressure chemical vapor deposition to deposit monocrystalline silicon over an area of 1.3m x 50cm, equivalent to over fourteen G12 wafers in a single pass. This is the largest area ever achieved for epitaxial silicon deposition. With demonstrated deposition rates of 5μm per minute and temperature uniformity achieving a total thickness variation (TTV) below 40%, the ProCon platform represents a significant leap in manufacturing scalability.

Market Traction

NexWafe secured conditional purchase orders for gigawatt-scale production, targeting both conventional utility-scale and space markets. These agreements demonstrate NexWafe’s commercial readiness and potential to reshore manufacturing to India, North America and Europe with significant projected CapEx and OpEx savings per gigawatt. At scale, EpiNex wafers also reduce CO2 emissions by 40%, aligning with the industry’s decarbonization goals.

“We’re seeing tremendous interest from solar cell manufacturers, especially in the U.S. and India, seeking a domestic supply of wafers. We’ve secured over 5GW in conditional supply agreements for mainstream solar markets and 250MW for ultra-thin cells for specialist applications, including space,” said Jonathan Pickering, NexWafe’s Vice President of Business Development in the U.S.

The company was spun out from Fraunhofer Institute for Solar Energy Systems ISE in 2015 and is a member of the Ultra Low-Carbon Solar Alliance, Solar Power Europe, and the European Solar Manufacturing Council.