In semiconductor manufacturing, material selection can make or break a process. The environment is highly demanding, with high heat, aggressive chemicals, ultra-precise tolerances, and an absolute need to eliminate contamination. It’s no place for trial and error. Choosing the right material under these conditions is imperative—cutting down on failures, increasing yields, and ultimately protecting delicate processes.

Why Material Selection Matters

Engineering and high-performance polymers play a critical role in Semiconductor manufacturing. When specifying components for wafer-handling equipment, seal rings, test sockets, or any part interacting with critical surfaces, you can’t afford guesswork. A well-chosen material ensures reliability, protects processes, and meets the rigorous demands of semiconductor manufacturing. Several factors should be considered when investigating thermoplastics to ensure the best outcome.

  • Chemical Resistance—Semiconductor etching and cleaning often involve harsh chemicals (HF, HCl, NH4OH, and more). A component in contact with these chemicals must maintain its integrity.
  • Thermal Stability—High-temperature processes like chemical vapor deposition (CVD) or solder reflow require thermoplastics that can perform under high temperatures.
  • Dimensional Stability — When dealing with sub-micron features, even a tiny dimensional change can lead to significant defects or misalignment during wafer processing.
  • Low Particulate Generation — This is crucial as any contamination can ruin semiconductor wafers.
  • Mechanical Strength and Wear Resistance — Constant handling and contact with abrasive surfaces require materials with robust wear resistance to maintain integrity and prevent particle shedding.
  • Electrostatic Properties — Many processes require materials to dissipate or conduct static electricity to protect sensitive components.
  • Low Outgassing — This is essential for vacuum environments to prevent contamination and ensure process integrity.

Additionally, lifecycle and reliability should be considered. Engineers must weigh the upfront cost of materials against their durability and performance over time. High-performance polymers often reduce total lifecycle costs by minimizing maintenance and replacement needs.

Material Selection Process

Choosing the right material isn’t just about matching specifications—it’s about a methodical approach that considers the nuances of each application. Partnering with a precision injection molder or machining expert experienced in high-performance thermoplastic will ensure you have the expertise you need to make this critical decision

Steps to Effective Material Selection

  1. Define Requirements
    Clearly outline the environmental and operational conditions, along with performance metrics such as temperature tolerance, chemical resistance, dimensional stability, and electrical properties. Include long-term considerations like UV exposure, vacuum compatibility, and material lifecycle to ensure the selected material meets operational and regulatory demands over its intended lifespan.
  2. Assess Application Challenges
    Consider factors such as exposure to plasma, extreme heat, aggressive chemicals, or mechanical stresses. Evaluate how these stressors may vary across the product’s lifecycle or under unexpected conditions, ensuring the solution accounts for worst-case scenarios.
  3. Determine Manufacturing Method
    Evaluate whether the part will be CNC machined, injection molded, or require a hybrid approach, as this directly impacts material selection. Injection molding is ideal for high-volume production and complex geometries but may necessitate materials with better flow characteristics and moldability. CNC machining, on the other hand, is suited for lower volumes, tight tolerances, and applications where material properties must remain uncompromised by molding processes. Consider how these methods influence lead times, costs, and material performance.
  4. Evaluate Material Options
    Match the application requirements with material properties. For example:

    • Polyetheretherketone (PEEK) — Known for its exceptional thermal stability, chemical resistance, and wear properties, PEEK is indispensable for applications such as CMP rings, wafer-handling components, plasma etching chambers, and carriers, where high temperatures and mechanical demands prevail.
    • Polytetrafluoroethylene (PTFE) — With unparalleled resistance to chemical corrosion, PTFE is the material of choice for handling aggressive chemicals, ensuring reliability in semiconductor processing environments.
    • Polyimide (PI) — Engineered for extreme thermal cycling with minimal outgassing, PI is highly suitable for robotic end-effectors in wafer transfer systems and other applications exposed to thermal extremes.
    • Polyphenylene Sulfide (PPS) — PPS combines excellent chemical resistance and mechanical stability, making it ideal for pump and valve components operating in corrosive environments where the heat demands do not exceed the capabilities of PEEK.
    • Polyetherimide (PEI) — Offering a balance of thermal resistance and chemical stability, PEI excels in applications such as test sockets, jigs, and fixtures that must endure elevated temperatures and repeated chemical exposure.
  5. Prototype and Test
    Prototype parts using selected materials to validate performance under real-world conditions. Testing for dimensional stability, wear resistance, ESD performance, and contamination resistance in controlled environments can help identify potential issues early.
  6. Refine Based on Results
    Use testing feedback to refine material choices and manufacturing processes. Collaboration with material experts, mold designers, and machining professionals can streamline this phase, ensuring adjustments align with functional requirements and cost considerations.

Why Ensinger?

If you’re navigating the challenges of material selection for semiconductor applications, Ensinger’s expertise and high-performance and engineering plastics can help. Our team is ready to provide guidance tailored to your specific needs, whether you’re optimizing a new design or refining an existing process. Reach out to explore how we can work together to make your next project successful.