PERC Cell/Module Manufacturing Patent Landscape
PERC cell and module manufacturing IP is heavily concentrated among a small cluster of Chinese manufacturers, with Zhejiang Aiko Solar and Tongwei Solar group entities collectively anchoring the top of the ranking. Annual filing volume peaked in 2021 and has since eased sharply, signalling a field past its growth phase as industry attention shifts toward next-generation architectures.
Chinese manufacturers dominate a concentrated field
Zhejiang Aiko Solar Energy Technology leads the ranking among the hundred largest filers, followed closely by Hengdian Group DMEGC Magnetics and Tongwei Solar Energy (Chengdu), each with comparable counts. The top five filers together account for 31% of the hundred largest filers’ combined total, pointing to a moderately concentrated but not monopolised competitive structure.
A clear tier gap separates the top cluster — Zhejiang Aiko Solar, DMEGC Magnetics, and the multiple Tongwei Solar subsidiaries — from the broader tail of single-digit filers. International players such as Resonac, DuPont, and Hanwha Q Cells appear in the ranking but are substantially outpaced by the Chinese-domiciled group.
| # | Applicant | Patent records | Share |
|---|---|---|---|
| 1 | Zhejiang Aiko Solar Energy Technology Co., Ltd. | 14 | |
| 2 | Hengdian Group DMEGC Magnetics Co., Ltd. | 13 | |
| 3 | Tongwei Solar Energy (Chengdu) Co., Ltd. | 13 | |
| 4 | Guangdong Aiko Solar Energy Technology Co., Ltd. | 11 | |
| 5 | Resonac Corporation | 8 | |
| 6 | Jiangsu Shunfeng New Energy Technology Co., Ltd. | 7 | |
| 7 | CSI Cells Co., Ltd. | 6 | |
| 8 | Jineng Clean Energy Technology Ltd. | 5 | |
| 9 | Tongwei Solar (Anhui) Co., Ltd. | 5 | |
| 10 | Tongwei Solar (Hefei) Co., Ltd. | 5 |
| # | Applicant | Patent records | Share |
|---|---|---|---|
| 11 | Tianjin Aiko Solar Energy Technology Co., Ltd. | 4 | |
| 12 | EI DU PONT DE NEMOURS & CO | 4 | |
| 13 | Hanwha Corporation | 3 | |
| 14 | Solar Paste LLC | 3 | |
| 15 | Tongwei Solar (Jintang) Co., Ltd. | 3 | |
| 16 | Tongwei Solar Energy (Meishan) Co., Ltd. | 3 | |
| 17 | Wuxi Suntech Power Co., Ltd. | 3 | |
| 18 | Avalon Solar Tech Pty Ltd. | 3 | |
| 19 | Hanwha Q Cells GmbH | 3 | |
| 20 | TNO (Netherlands Organisation for Applied Scientific Research) | 3 |
The leaders’ positions reflect deep integration across cell-process steps: semiconductor device engineering (H01L) dominates their portfolios, with select players adding coverage in printing, metallisation, and coating. This broad process-level IP base creates meaningful barriers for late entrants attempting to design around established process sequences.
Filing counts for 2024–2025 are subject to publication lag and will likely revise upward; the apparent near-zero recent figures should not be read as activity cessation. Longer-window growth, applicant concentration, and technology-route coverage are therefore more reliable signals than the latest-year bar alone.
Activity peaked in 2021 and technology mix is overwhelmingly device-centric
The filing trend reveals a field that expanded through the late 2010s, spiked in 2021, and has since contracted. The technology composition shows that semiconductor device engineering dominates, with a long tail of adjacent process and materials branches.
Annual filing trend
Filings held steady at roughly 20 per year from 2017 to 2019, dipped in 2020, surged to 24 in 2021, then fell sharply in 2022 and 2023. Years 2024 and 2025 show near-zero counts, which reflects publication lag rather than a real halt in activity — those years should be treated as incomplete.
↗ Hover for values · click a bar to ask EurekaTechnology composition
H01L (semiconductor devices) dominates the branch mix by a wide margin, consistent with a field focused on cell-level device engineering. Adjacent branches — H02S (photovoltaic system integration), C03C (glass and enamel), H01B (conductors and metallisation), and C23C (coating and surface deposition) — each represent a small share, indicating that most filers have not yet extended IP coverage to module-level assembly, interconnection, or encapsulation processes.
↗ Hover for values · click a bar to ask EurekaHighly cited patent families surfaced by the query
Citation-heavy patent families returned by the query. Use this section as citation context, not as a curated list of the most topic-specific patents.
A process for preparing passivated emitter rear co…
A process for preparing a passivated emitter rear contact solar cell, which includes the steps as follows: removing the damaged layer on the surface of the silicon wafer and at the same time polishing both surfaces, texturing, forming PN junction, etching, removing the glass impurity, depositing a passivation film on the back surface, depositing a… (excerpt from the patent abstract)
Open this patent in Eureka →| # | Patent | Citations |
|---|---|---|
| 1 | 一种三层介电钝化膜PERC太阳电池及制作工艺 | 56 |
| 2 | Aluminum pastes and use thereof in the production … | 44 |
| 3 | 一种碱抛光高效PERC电池及其制备工艺 | 40 |
| 4 | Process for the formation of a silver back electro… | 35 |
| 5 | 纳米硅硼浆及其应用于制备PERL太阳能电池的方法 | 33 |
| 6 | 一种高转换效率SE-PERC太阳能电池的制备方法 | 29 |
| 7 | 一种PERC电池的制备方法 | 27 |
| 8 | P型异质结全背电极接触晶硅光伏电池制备方法 | 24 |
Ranked by total forward citations. Citation counts favour older and broadly cited patent families, and broad or adjacent patents may appear when they match the search scope. Treat this section as citation context, not as a curated list of the most topic-specific patents. Some patent titles may be shown in their original, non-English language where an accurate translation could not be guaranteed.
What the patent structure means for R&D investment decisions
Three structural features stand out: the technology is past its filing peak, IP is concentrated in device-level process patents, and co-filing is almost entirely intra-group. Each has direct implications for where new R&D spend is likely to find freedom to operate.
Past peak — field in decline phase
Annual filings peaked in 2021 and have eased sharply since, placing PERC cell manufacturing in a decline stage. This trajectory is consistent with the industry’s broad pivot toward TOPCon and heterojunction architectures. Incremental PERC process improvements remain technically feasible but face a crowded prior-art landscape concentrated in H01L device engineering.
Lifecycle: DeclineTop-five filers hold 31% of the top-100 filers’ output
The top five filers account for 31% of the hundred largest filers’ combined patent records, with Zhejiang Aiko Solar at the front. Below that cluster, the field fragments into a long tail of smaller Chinese manufacturers, with only a handful of non-Chinese players — Resonac, DuPont, Hanwha entities — holding meaningful positions. The tier gap between the leading cluster and the tail is substantial.
Moderate concentrationCo-filing is intra-group; no cross-industry alliances evident
The most active co-filing pairs are entirely within corporate families: Zhejiang Aiko Solar with Guangdong Aiko Solar (8 joint records) and Tianjin Aiko Solar (3 records); Tongwei Solar subsidiaries co-filing across the Anhui, Hefei, Jintang, Meishan, and Chengdu entities. No cross-industry or university co-filing partnerships appear among the top collaboration pairs, suggesting that open-innovation routes into this field have not been heavily used.
Intra-group onlyChina-dominant filing with limited international extension
China accounts for the overwhelming majority of jurisdictional filings. The United States and Europe (EPO) each attract a much smaller slice, followed by WIPO PCT, India, and Malaysia. This skew suggests that many process-level patents were filed primarily to protect domestic manufacturing rather than to build a globally enforceable portfolio — which may leave freedom-to-operate in non-Chinese markets more accessible than the raw count implies.
China-centricGo beyond the landscape: Eureka’s TRIZ Solution agent breaks down an R&D problem and returns patented concept solutions, each with a technical approach and cited patent & literature evidence.
| Applicant | Collaborator | Co-filings |
|---|---|---|
| Zhejiang Aiko Solar Energy Technology Co., Ltd. | Guangdong Aiko Solar Energy Technology Co., Ltd. | 8 |
| Tongwei Solar (Anhui) Co., Ltd. | Tongwei Solar (Hefei) Co., Ltd. | 5 |
| Zhejiang Aiko Solar Energy Technology Co., Ltd. | Tianjin Aiko Solar Energy Technology Co., Ltd. | 3 |
| Tongwei Solar Energy (Chengdu) Co., Ltd. | Tongwei Solar (Jintang) Co., Ltd. | 3 |
| Tongwei Solar Energy (Chengdu) Co., Ltd. | Tongwei Solar Energy (Meishan) Co., Ltd. | 3 |
| Tongwei Solar Energy (Chengdu) Co., Ltd. | Tongwei Solar (Anhui) Co., Ltd. | 3 |
| Tongwei Solar Energy (Chengdu) Co., Ltd. | Tongwei Solar (Hefei) Co., Ltd. | 3 |
| Guangdong Aiko Solar Energy Technology Co., Ltd. | Tianjin Aiko Solar Energy Technology Co., Ltd. | 3 |
| Tongwei Solar (Anhui) Co., Ltd. | Tongwei Solar (Jintang) Co., Ltd. | 3 |
| Tongwei Solar (Anhui) Co., Ltd. | Tongwei Solar Energy (Meishan) Co., Ltd. | 3 |
Co-filing pairs, ranked by the number of jointly-filed patent families.
Aiko Solar leads; Tongwei group fields multiple subsidiaries
Two corporate groups — Aiko Solar and Tongwei Solar — collectively account for the majority of top-ranked positions. Their technology focus is almost entirely on H01L semiconductor device engineering, with narrow extensions into printing and metallisation.
Zhejiang Aiko Solar Energy Technology
The top-ranked filer with 14 patent records, Zhejiang Aiko Solar’s portfolio is concentrated in H01L 31 semiconductor device engineering, with marginal extensions into B23K (laser processing) and C23C (surface deposition). The related Guangdong Aiko Solar entity holds 11 records and Tianjin Aiko Solar a further 4, giving the Aiko group a combined presence that is the largest in the corpus. Momentum data for the Aiko entities is not separately captured in the recent-trend evidence.
patent records: 14Hengdian Group DMEGC Magnetics
Ranked second with 13 patent records, DMEGC Magnetics focuses its filings on H01L 31 semiconductor device engineering (13 records), with secondary coverage in H01L 21 process engineering and B41M printing processes — indicating attention to screen-printing metallisation, a critical PERC yield lever. Momentum data marks the entity as a new entrant in the most recent period, suggesting recent strategic entry rather than a long incumbent position.
patent records: 13| Applicant | Recent (3 yrs) | Trend |
|---|---|---|
| Hengdian Group DMEGC Magnetics Co., Ltd. | 2 | ▲ new entrant |
| Tongwei Solar Energy (Chengdu) Co., Ltd. | 1 | ▲ new entrant |
Module assembly, metallisation, and coating are under-served branches
While H01L device engineering is saturated, several adjacent IPC branches carry very low patent-record counts, suggesting that process steps upstream and downstream of the cell — encapsulation, interconnection, paste chemistry, and deposition — have received comparatively little dedicated IP coverage in this corpus.
C23C · Coating and surface deposition
With only 5 patent records and a 2% share of the corpus, coating and surface deposition processes for PERC rear-side passivation stacks are sparsely protected. Given that Al₂O₃ / SiNₓ passivation quality is a primary efficiency lever in PERC cells, this branch represents an under-served area with clear technical value. An entrant with novel ALD or PECVD process IP could build differentiated coverage with limited prior-art crowding in this specific branch.
Search this in Eureka →B23K · Welding, soldering and brazing
Only 4 patent records cover welding, soldering, and brazing processes — relevant to busbar and ribbon interconnection in PERC module assembly. As cell manufacturers extend downstream into module integration, interconnection process reliability becomes a key differentiator. The sparse filing count suggests that laser-welding and low-temperature bonding approaches for PERC modules remain an under-served area where new process IP could secure meaningful freedom-to-operate relative to the crowded cell-device layer.
Search this in Eureka →How leading filers differ across technology routes
Route coverage across the main technology branches in the current evidence set.
| Player | H01L 31 · Semiconductor devices | H01L 21 · Semiconductor devices | H02S 40 · Photovoltaic / solar power generation | C03C 8 · Glass & enamel compositions | H01B 1 · Cables, conductors & insulators |
|---|---|---|---|---|---|
| Hengdian Group DMEGC Magnetics Co., Ltd. | Strong · 13 | Moderate · 3 | Absent | Absent | Absent |
| Zhejiang Aiko Solar Energy Technology Co., Ltd. | Strong · 14 | Absent | Absent | Absent | Absent |
| Tongwei Solar Energy (Chengdu) Co., Ltd. | Strong · 12 | Absent | Absent | Absent | Absent |
| Guangdong Aiko Solar Energy Technology Co., Ltd. | Strong · 10 | Absent | Absent | Absent | Absent |
| Resonac Corporation | Strong · 5 | Absent | Strong · 5 | Absent | Absent |
| E.I. du Pont de Nemours and Company | Strong · 5 | Absent | Absent | Emerging · 1 | Moderate · 2 |
| CSI Solar (Suzhou) Technology Co., Ltd. | Strong · 6 | Absent | Absent | Absent | Absent |
Frequently asked questions
Within the top-100 ranked filers, Zhejiang Aiko Solar Energy Technology leads with 14 patent records, followed by Hengdian Group DMEGC Magnetics and Tongwei Solar Energy (Chengdu) each with 13. Multiple Aiko Solar and Tongwei Solar subsidiaries also appear in the top rankings, making both corporate groups the most active overall.
Evidence indicates the field is in a decline stage. Annual filings peaked in 2021 and have eased significantly since. Counts for 2024 and 2025 are subject to publication lag and will revise upward, but the multi-year trend is downward from the 2021 peak.
China is by far the dominant jurisdiction, accounting for the large majority of filings in the corpus. The United States and Europe (EPO) each attract a much smaller number of filings, followed by WIPO PCT, India, and Malaysia. This concentration reflects the location of the primary manufacturing base.
H01L (semiconductor devices) is the dominant IPC class by a wide margin, consistent with a focus on cell-level device engineering — passivation layers, selective emitter structures, and rear-contact formation. Adjacent branches such as coating (C23C), conductors and metallisation (H01B), and printing (B41F, B41M) are represented but at much lower counts.
Co-filing activity is almost entirely intra-group. The most active co-filing pairs are between subsidiaries within the Aiko Solar group and between subsidiaries within the Tongwei Solar group. No cross-industry or academic co-filing pairs appear among the top collaboration pairs in the evidence.
The sparsest adjacent branches relative to H01L are H02S (photovoltaic system integration, 8 records), C03C (glass and enamel compositions for encapsulation, 6 records), H01B (conductors and metallisation, 6 records), C23C (coating and surface deposition, 5 records), and B23K (welding and interconnection, 4 records). These branches represent under-served areas where dedicated process IP is comparatively limited.
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