The plasma cleaning machine is a core surface treatment equipment in the entire photovoltaic manufacturing process. Through atomic-level cleaning, surface activation, and micro-etching, it addresses pain points such as contamination, oxidation, poor adhesion, efficiency degradation, and low reliability in silicon wafers, solar cells, and module packaging. It is a key process for enhancing photovoltaic conversion efficiency, yield, and lifespan.
1. Core working principle
In a vacuum or atmospheric pressure environment, gases such as O₂, Ar, H₂, and N₂ are ionized to form low-temperature plasma, which acts on the surface of photovoltaic materials through a triple mechanism: physical bombardment, chemical reaction, and surface modification
Physical bombardment: High-energy ions strip micro-dust, metal particles, oxide layers, and phosphosilicate glass (PSG) from the surface of silicon wafers/glass/backplanes, achieving nanoscale cleanliness.
Chemical reaction: Active radicals (O・, H・) decompose organic matter, oil stains, mold release agents, and tape residue, generating volatile gases such as CO₂ and H₂O, which are then emitted.
Surface activation: Introducing polar groups such as -OH, -COOH, and -NH₂ to enhance surface energy (from 28 to 45 dyne), reduce water droplet angle (<25°), and improve the adhesion of coatings, adhesive films, and silver paste.
Micro-etching: Precisely etch the surface of silicon wafers to form a textured structure, reducing light reflection and enhancing light absorption efficiency.
II. Key application scenarios of the entire photovoltaic process
1. Silicon wafer/wafer manufacturing process
Cleaning after silicon wafer cutting: Remove cutting fluid residue, silicon powder, and metal ions to avoid contamination spread and improve subsequent texturing/diffusion uniformity.
Activation/etching before texturing: Assists in optimizing the texture structure of polycrystalline silicon, increases the specific surface area, enhances light-harvesting capability, and boosts the conversion efficiency by approximately 5%.
Cleaning before diffusion/coating: Remove the oxide layer and impurities on the silicon wafer surface to ensure the uniformity of the PN junction and enhance the adhesion of passivation films (SiNₓ, Al₂O₃).
2. Cell manufacturing (PERC/TOPCon/HJT/ perovskite)
Phosphorus Silicate Glass (PSG): Replacing wet etching, it eliminates the need for wastewater and damage. It removes the phosphorus silicate glass on the surface after diffusion, ensuring the quality of the anti-reflective coating/passivation film.
Electrode/Silver Paste Pretreatment: Clean the surface of the silicon wafer, enhance the adhesion of silver paste printing, reduce false printing, missed printing, and electrode detachment, and lower the series resistance.
Activation before passivation/anti-reflective coating: Enhances the adhesion between thin films such as SiNₓ, Al₂O₃, TiO₂ and silicon wafers, improving passivation effect, PID resistance, and long-term reliability.
HJT/TOPCon battery: Clean amorphous silicon/polycrystalline silicon interface, enhance carrier transport efficiency, open-circuit voltage (Voc), compatible with heterojunction and tunneling oxide layer processes.
Perovskite solar cells: Low-temperature plasma treatment of ITO/FTO glass and flexible substrates in a glove box to remove oxide layers and enhance surface energy, resulting in a 40% improvement in perovskite film uniformity and an efficiency increase of 0.5~1.2%.
3. Photovoltaic module packaging process (core application)
Photovoltaic glass pretreatment: Remove release agents, oil stains, and fingerprints from the glass surface to enhance the bonding strength with EVA/POE adhesive films, preventing delamination, water ingress, and yellowing.
Activation of backsheet surface: Treating fluorine-containing backsheets (PET + fluorine film) breaks the surface inertia, doubles the surface energy, and solves the problem of insufficient peeling force between EVA and the backsheet.
Cleaning before cell string welding: Clean the oxide layer and impurities on the surface of the silver grid lines to enhance the welding strength and conductivity of the ribbons, and reduce the risks of cold solder joint and hot spots.
Overall activation before film bonding/encapsulation: Simultaneous treatment of glass, solar cells, and backsheets, with interlayer adhesion increased by 300%, enhancing the module's airtightness, weather resistance, and reliability for a 25-year lifespan.
4. Application of supporting processes
Graphite boat cleaning: Efficiently removes silicon nitride and silicon powder deposited on the surface of the graphite boat, replacing traditional 16-20 hours of wet cleaning. It is chemical-free and offers a 10-fold increase in efficiency.
Frame/junction box pretreatment: Activate the surface of aluminum alloy frames and plastic junction boxes to enhance their adhesion with sealant and prevent rainwater infiltration.
III. Core Advantages of Pulesi Photovoltaic Plasma Cleaning Machine
Atomic-level cleanliness: Cleaning accuracy reaches 0.1nm, completely removing nanoscale contaminants, with efficiency loss reduced by more than 3%.
Low-temperature and non-destructive: processing temperature < 50℃, without damaging silicon wafers, passivation films, perovskite materials, or optical glass.
Strong process adaptability: compatible with PERC, TOPCon, HJT, perovskite, and flexible photovoltaic full technology routes, supporting vacuum batch processing, atmospheric online processing, and roll-to-roll processing.
Environmentally friendly: Dry process, no wastewater, no chemical waste liquid, in line with photovoltaic green manufacturing and RoHS standards.
High efficiency in mass production: Wide-format and atmospheric models are compatible with high-speed assembly lines, while vacuum models support batch processing of multiple trays/boxes, resulting in a yield increase of 5%-20%.
Precision and controllability: MFC gas control, PLC + touch screen, parameterized formula, batch consistency ≥98%.
Pulesi provides customized plasma cleaning machines specifically for photovoltaics, free sample testing, and process optimization, covering the entire process from silicon wafers to modules, helping photovoltaic manufacturers break through efficiency and yield bottlenecks.
