The latest Alkaline Polish tool from SCHMID offers 10,000 wafers/hour throughput while enabling process temperatures up to 90°C and advanced cleaning with KOH, HF/HCl, and O₃ or H₂O₂
The Alkaline Si Wraparound Removal tool is now more compact at 13.7 m footprint and 7,000 kg weight, yet supports aggressive etching at 90°C
Both systems retain high performance, with throughputs of up to 10,000 wafers/hour and mechanical yields of 99.95%
Removing doped glass layers and treating wraparound regions are critical steps in advanced cell concepts such as TOPCon and BC. Single-sided wet-chemical platforms are widely applied for these processes, ensuring precise etching while maintaining high yields and throughput.
For the latest TaiyangNews Market Survey on Solar Cell Production Equipment 2025, SCHMID has provided data for 2 products, as in the previous survey, but both feature updated specifications. The company’s latest Alkaline Polish tool builds on the capabilities of its earlier Alkaline Polish/Doped Glass Etch tool, offering greater process flexibility and a wider application scope while maintaining key performance levels. Like its predecessor, this tool offers a maximum throughput of 10,000 wafers per hour, with a mechanical yield of 99.95% and 97% uptime. It utilizes the same core chemistry – a mix of HF and KOH with additives – but now operates at higher process temperatures of up to 90°C, enabling faster reactions and compatibility with more demanding chemistries. The tool also features an enhanced cleaning regime that combines KOH, HF/HCl, and either ozone (O3) or hydrogen peroxide (H2O2), offering a more advanced setup compared to the simpler HF/HCl + H₂O₂ cleaning used in the earlier version. The footprint has increased slightly to 21.5 x 4.9 m (up from 21 x 4.3 m), while the weight has been reduced from 12,000 kg to 11,000 kg, most likely because of material improvements and design refinements (see SCHMID’s Inline Alkaline Texturing For Advanced Solar Cells).
These updates are also reflected in the Alkaline Si Wraparound Removal tool. This model is now more compact, with a footprint of 13.7 m (down from 20 m) and a reduced weight of 7,000 kg (from 12,000 kg). The maximum operating temperature has increased from 80°C to 90°C, supporting more aggressive etching processes for polysilicon wraparound removal. The cleaning chemistry has shifted from HF/HCl + H2O2 to a KOH and O3 formulation, offering improved post-process cleaning. Despite its smaller size, the system maintains performance, with a maximum throughput of 10,000 wafers per hour, an average of 9,000 wafers per hour, and a mechanical yield of 99.95%.
The text is an edited excerpt from TaiyangNews’ latest Market Survey on Solar Cell Production Equipment 2025, which can be downloaded for free here.