Electronic products often face insulation challenges brought by high voltage and complex electric fields. Traditional electrical assembly processes struggle to eliminate the risk of arcing, while potting technology, which utilizes liquid materials that cure into polymeric insulating media, has become a core protective solution to this problem. The potting process involves injecting liquid potting materials into the cavities or molds containing electronic components and circuits, either mechanically or manually, allowing them to cure and form high-performance polymer insulation. This process replaces the air gaps between components with solid media, reinforcing the structure and significantly enhancing the product's dielectric strength.

In electronic product manufacturing, low surface energy materials such as polyester (PET), polyimide (PI), ethylene-tetrafluoroethylene copolymer (ETFE), polytetrafluoroethylene (PTFE), and nylon are widely used. These materials have nano-smooth surfaces, lack hydrophilicity, and are chemically inert, resulting in poor wetting and adhesion with potting resins and insufficient bonding strength. Under harsh conditions like temperature cycling and thermal vacuum, interlayer delamination and adhesion failures can easily occur, directly threatening product safety. Therefore, surface modification of these materials before potting to enhance their bonding performance with the potting materials becomes a key step in ensuring product quality.

Plasma Treatment Technology: Core Principles and Technical Advantages

Plasma, as the fourth state of matter distinct from solid, liquid, and gas, consists of partially ionized gas containing electrons, ions, free radicals, and various active groups. Plasma treatment technology utilizes these highly reactive particles to interact with material surfaces under low-temperature conditions, achieving cleaning, activation, and etching of the surface through physical and chemical reactions.

The typical workflow for this technology is as follows: process gases such as oxygen, argon, or nitrogen-hydrogen mixtures are introduced into a vacuum chamber, and then ionized using radio frequency (RF) or microwave energy to generate plasma. When these active particles act on the material surface, surface modification is achieved through multiple mechanisms:

Physical bombardment: High-energy particles like argon ions act like a "microscopic sandstorm," breaking down organic contaminants' molecular chains and promoting their volatilization.

Chemical action: Active groups such as oxygen radicals react with contaminants through oxidation, producing volatile substances like carbon dioxide and water vapor, which are then removed by the vacuum system.

Surface activation: While removing surface contaminants, plasma can introduce polar groups such as hydroxyl (-OH) and carboxyl (-COOH) onto the material surface, significantly enhancing surface energy and hydrophilicity.

Compared to traditional surface treatment methods, plasma treatment technology shows several transformative advantages:

Ultra-clean treatment capability: Can remove nanoscale contaminants, achieving molecular-level surface cleanliness.

Precise and controllable modification: Acts only within a few nanometers of the material surface, without damaging the material's bulk properties.

Environmental and safety benefits: Uses an entirely dry process without toxic chemical solvents, with harmless gas as the only reaction by-product.

High efficiency and stability: Process parameters can be precisely controlled, ensuring uniform and consistent surface treatment results.

The Application Value of Plasma Treatment Technology in the Potting Process

Introducing a plasma treatment step before the potting process can fundamentally resolve the interface adhesion issues between low surface energy materials and potting resin, providing a solid guarantee for the quality of electronic product potting.

1. Strengthening Potting Adhesion

For substrates such as PCB boards and plastic housings treated with plasma, surface energy is significantly enhanced, and the surface properties change from hydrophobic to hydrophilic. When liquid potting resin flows over the substrate surface, it can spread quickly and evenly, and penetrate into the fine gaps of components. Once the potting resin cures, it forms a stable mechanical interlock structure and chemical bonds with the substrate, effectively preventing defects such as interface delamination and voids.

2. Improving Product Reliability

A stable interface adhesive effect can provide products with better sealing, higher insulation strength, and excellent thermal conductivity. This is crucial for electronic products used long-term in harsh environments such as automotive electronics, aerospace equipment, and outdoor communication base stations, which face humidity, vibration, and temperature cycling. It can significantly reduce early failure risks and effectively extend the product's lifespan.

3. Optimizing Overall Production Process

Plasma treatment provides a stable and repeatable high-quality interface foundation for subsequent potting processes, reducing excessive reliance on the flow properties of potting resin during production. Meanwhile, product rework and scrap rates caused by poor adhesion are greatly reduced, helping enterprises improve overall production yield and processing efficiency.

It can be said that plasma treatment technology, with its unique technical advantages, is becoming a core supporting technology for promoting the upgrade of electronic product potting processes and ensuring stable product performance.