Ultra-High Purity Stainless Steel Coil Tube — SEMI F20 Certified Piping & Valves
Product Overview
This ultra-high purity (UHP) stainless steel coil tube is engineered and manufactured in strict compliance with the SEMI F20 standard — the industry-defining specification for ultra-high purity piping, fittings, and valves used in semiconductor fabrication facilities. Developed by Wenzhou Jixing Metal Materials Co., Ltd., this coil tube product is designed as a complementary system component to the SEMI F19 ultra-high purity tubing specification, covering the full range of connecting fittings, flanges, and valve assemblies required for contamination-critical process applications.
SEMI F20 establishes rigorous requirements for material purity, surface finish, particulate cleanliness, and hydrodynamic performance to ensure that no contamination is introduced into sensitive semiconductor chemical delivery systems. This product represents the highest tier of purity achievable in industrial stainless steel piping components, meeting the exacting demands of advanced node semiconductor manufacturing.
Material & Properties
- Base Material: ASTM A270 Type 316L / 304L / 904L / Alloy 60 (C-276) seamless stainless steel, selected based on process fluid compatibility and corrosion resistance requirements.
- Purity Grade: Ultra-high purity grade with trace element limits controlled to parts-per-billion (ppb) levels, ensuring minimal outgassing and elemental contamination.
- Surface Finish: Electropolished interior surface with Ra ≤ 0.16 μm (6 μin) finish, providing a smooth, low-particulate-release channel for chemical transport.
- Corrosion Resistance: Superior resistance to fluorinated acids, halogenated solvents, and high-purity wet chemical delivery systems common in semiconductor etching, cleaning, and deposition processes.
- Mechanical Properties: Tensile strength ≥ 485 MPa (316L), elongation ≥ 40%, with full traceability to mill heat numbers.
- Non-Magnetic: Certified non-magnetic to eliminate interference with sensitive process instrumentation.
Specifications
| Parameter | Specification |
|---|---|
| Governing Standard | SEMI F20 (Ultra-High Purity Piping & Valves) |
| Complementary Standard | SEMI F19 (Ultra-High Purity Tubes) |
| Industry Classification | Semiconductor |
| Product Category | Coil Tube — Connecting Fittings & Assemblies |
| Available Materials | 304L, 316L, 904L, Alloy 60 (C-276) |
| Interior Surface Finish | Ra ≤ 0.16 μm (Electropolished) |
| Exterior Surface Finish | Bead Blast / Passivated / 2B |
| Typical OD Range | 3/8" – 6" (10 mm – 150 mm) |
| Wall Thickness | 0.5 mm – 6.35 mm (custom available) |
| Pressure Rating | ASME B31.3 compliant; up to 1500 PSIG depending on size and material |
| Temperature Range | -196°C to +400°C (material dependent) |
| Connection Types | Butt Weld, VCR, VCO, Tri-Clamp, Flanged |
| Coil Diameter | Custom — typically 1.0 m to 3.0 m |
| Coil Length | 5 m to 100+ m per coil |
| Passivation Treatment | ASTM A967 / ASTM A380 compliant |
| Hydrostatic Test | 1.5× working pressure, minimum 5 minutes hold |
| Particle Count | ≤ 25 particles ≥ 0.5 μm per liter (post-clean) |
Manufacturing Process
The production of SEMI F20 compliant coil tubes follows a tightly controlled, multi-stage manufacturing process designed to minimize contamination at every step:
- Raw Material Selection: Only certified ultra-high purity stainless steel seamless tubing is sourced, with full traceability to mill certifications and chemical composition analysis verified against SEMI F20 elemental limits.
- Precision Coil Forming: Cold-rolled tubing is formed into coils using high-precision roll-forming equipment that maintains dimensional tolerances within ±0.05 mm without introducing work-hardening or surface damage.
- Butt Weld Fabrication: All weld joints are executed by certified welders using inert gas (argon) shielded TIG welding in a controlled atmosphere, producing smooth, continuous weld seams with no porosity or oxide inclusions.
- Electropolishing: The interior surface undergoes precision electropolishing to achieve Ra ≤ 0.16 μm, removing micro-roughness, dissolved metals, and surface contaminants through controlled electrochemical dissolution.
- Acid Pickling & Passivation: Components are pickled and passivated per ASTM A967 to remove all residual oxide films and establish a protective chromium-rich passive layer.
- Ultra-Pure Water Flushing: Final cleaning is performed using ultra-pure water (≤ 1 μS/cm) at controlled flow rates to remove any particulate or ionic contamination.
- Inspection & Testing: Each coil undergoes hydrostatic pressure testing, visual inspection, and optional helium leak detection. Spectroscopic analysis (OES) verifies chemical composition.
- Clean Packaging: Finished coils are sealed in clean-room environments with protective end caps, desiccant, and anti-static wrapping to maintain purity until installation.
Applications
SEMI F20 compliant ultra-high purity coil tubes and fittings are critical infrastructure components in the following semiconductor and related industries:
- Chemical Mechanical Planarization (CMP): Delivery of ultra-pure slurry and rinse water to wafer polishing systems.
- Wet Etching & Cleaning: Transport of high-purity acids (HF, HCl, HNO₃), bases, and organic solvents for wafer surface preparation.
- Chemical Vapor Deposition (CVD) & Physical Vapor Deposition (PVD): High-purity precursor gas and carrier gas delivery systems.
- Photoresist Coating: Ultra-pure solvent and resist fluid distribution networks.
- Wafer Rinse Systems: Megahohmic (MΩ) ultra-pure water (UPW) delivery and recirculation loops.
- Solar Cell Manufacturing: High-purity chemical delivery for thin-film deposition processes.
- Pharmaceutical & Biotech: Sterile process piping where ultra-low particulate and metal ion release is required.
Quality Certifications & Compliance
- SEMI F20: Full compliance with the Ultra-High Purity Piping and Valves specification, covering all requirements for connecting fittings, flanges, valves, and assemblies.
- SEMI F19 Compatibility: Designed for seamless integration with SEMI F19 ultra-high purity tubing systems.
- ISO 9001:2015: Certified quality management system ensuring consistent production quality.
- ASME B31.3: Process piping design and pressure rating compliance.
- ASTM A967: Chemical cleaning and passivation of stainless steel parts.
- ASTM A380: Chemical passivation treatments for stainless steel.
- Mill Traceability: Full material traceability from mill heat number through final product serialization.
Key Differentiators
Complete F20/F19 System Solution: Unlike suppliers offering only tubing or only fittings, Wenzhou Jixing provides an integrated coil tube product that covers the full SEMI F20 scope — connecting fittings, valve assemblies, and coiled piping — enabling turnkey ultra-high purity system delivery.
- Sub-0.16 μm Electropolished Interior: Industry-leading surface finish minimizes particulate generation and fluid stagnation, reducing contamination risk to the lowest achievable level.
- Full Traceability: Every coil is serialized with complete documentation from raw material mill certification through final inspection, satisfying the most stringent customer audit requirements.
- Custom Coil Configuration: Flexible coil diameters and lengths tailored to specific fab layout requirements, reducing field splicing and installation complexity.
- Multi-Material Offering: Availability in 304L, 316L, 904L, and Alloy 60 provides solutions for the widest range of chemical compatibility challenges in semiconductor processing.
- Contamination-Controlled Manufacturing: Clean-room packaging and controlled handling protocols ensure product purity is maintained from fabrication through delivery to the fab floor.