This landscape identifies 108 patent families filed between 2015 and the mid-2026 data cut-off, scoped to claims combining PERC cell architecture with anti-reflective coating, SiNx ARC layers, texturing or light-trapping structures. The true figure filed to date is likely somewhat higher, because publication typically lags filing by around 18 months, so the most recent one to two years are undercounted. Patent families, rather than raw document counts, are the more reliable unit here because they neutralise duplicate filings across jurisdictions and continuation applications.

No. Filings peaked in 2019 at 24 in this dataset, fell to 10 by the 2022 midpoint, and have continued to decline since. This pattern indicates that the core claim space around texturing and ARC deposition filled in relatively quickly, with later filings adding narrower variations rather than new fundamental approaches. It does not mean the underlying technology has stopped being used commercially — PERC remains a mainstream cell architecture — only that the patenting pace around this specific optical-stack topic has cooled.

Filing activity in this space clusters around a small number of Chinese cell manufacturers, with the Aiko group (filing under Zhejiang Aiko, Guangdong Aiko and Tianjin Aiko entity names) showing the strongest internal co-filing pattern at 21 shared filings between two of its entities. Tongwei Solar's various regional subsidiaries and other manufacturers such as Jiangsu Shunfeng Photovoltaic also appear in the assignee set, though none show filing activity in the most recent tracked year. Because several of these are sibling entities under one corporate parent, raw assignee counts should be read as a group total rather than as independent competitors.

China (CNIPA) carries the heaviest claim density in this dataset, with 79 of 108 families filed there, so device-level ARC and texturing claims are most crowded in that jurisdiction. The US, India and the EPO each show single-digit-to-low-double-digit filing counts, suggesting comparatively lighter coverage — though this reflects filing volume, not necessarily weaker claim scope, so a proper freedom-to-operate search is still needed before relying on it. Process-level classes such as cleaning, welding and printing show only one or two filings globally and may offer more open claim space regardless of jurisdiction.

US20170294545A1, filed by CSI Cells Co., Ltd. and published in October 2017, describes a PERC fabrication process that pairs catalytic metal-etch texturing producing a nanometer-level textured structure with a passivating antireflective layer on the front surface and a separate passivation film on the back. It is a process claim covering a specific sequence — damage-layer removal and polishing, texturing, junction formation, etching, dual-side passivation, local back openings, and screen-print metallisation — rather than a claim over ARC materials or texturing chemistry in general. Anyone using a different texturing mechanism (for example wet alkaline or laser texturing rather than catalytic metal etch) or a different sequencing of the passivation and metallisation steps sits outside its literal scope, though a full claim chart review is needed before relying on that distinction.