Product Specification

Product Positioning & Value Proposition

The Silicon Carbide (SiC) Horizontal Process Tube is the primary pressure boundary and clean process chamber used in high-temperature gas-phase reactions and heat treatment for semiconductor, photovoltaic, and advanced materials manufacturing.

The product adopts a 3D-printed monolithic SiC body + CVD SiC functional coating architecture, combining high thermal conductivity, low contamination, high mechanical strength, and chemical durability. It is optimized for processes that demand low particle/gas contamination, excellent temperature uniformity, and long-term stability.

Core value:

• Push the tool’s temperature uniformity, cleanliness, and OEE to a higher level.

• Extend replacement intervals and shorten cleaning downtime to optimize Total Cost of Ownership (TCO).

• Provide a long-life, low-risk chamber solution for oxidative and chlorine-bearing chemistries at elevated temperature.

Applicable Atmospheres & Process Window

• Working atmospheres

  • Reactive gases: oxygen (O₂) and other oxidizing mixtures

  • Carrier/protective gases: nitrogen (N₂) and high-purity inert gases

  • Compatible species: trace chlorine-bearing gases (concentration and residence time controlled by recipe)

• Typical processes: dry/wet oxidation, anneal, diffusion, LPCVD/CVD deposition, surface activation/modification, PV passivation, functional thin-film formation, carbonization/nitridation, etc.

• Temperature range: ambient to 1250 °C (recommend 10–15% safety margin depending on heater design and ΔT constraints)

• Pressure range: from slight vacuum/LPCVD negative pressure to near-atmospheric positive pressure (final rating per PO/spec).

Materials & Structural Rationale

1. Monolithic SiC body (additive manufactured)

   • High-density β-SiC or multi-phase SiC; single-piece construction eliminates seams and braze joints that can create micro-leaks or stress concentrators.

   • High thermal conductivity (vs. alumina/quartz) supports rapid thermal response and improved axial/radial uniformity.

   • Low, stable CTE yields better high-temperature dimensional stability and seal integrity.

2. CVD SiC functional coating

   • In-situ deposited, dense and ultra-pure (surface/coating impurities < 5 ppm); minimizes particle shedding and metal ion release.

   • Outstanding chemical inertness toward oxidizing and chlorine-bearing gases; mitigates wall attack and re-deposition.

   • Zonal thickness tailoring available to balance corrosion resistance with thermal response.

3. Composite benefits

   • Body provides mechanical support + heat conduction; coating provides corrosion resistance + cleanliness—a system-level optimum for reliability and throughput.

Key Performance Targets 

• Max continuous use temperature: 1250 °C

• Substrate (bulk body) total impurities: < 300 ppm

• CVD SiC coating/surface impurities: < 5 ppm

• Dimensional tolerances (typical): OD ±0.3–0.5 mm; coaxiality ≤ 0.3 mm/m (tighter upon request)

• Inner-wall roughness: Ra ≤ 0.8–1.6 µm (fine polish / near-mirror optional)

• Leak tightness (helium): ≤ 1×10⁻⁹ Pa·m³/s (per tool class)

• Thermal shock stability: supports repeated hot-cold cycling with no visible cracking or spallation (type-test report supplied)

• Cleanliness: final clean/assembly in ISO Class 5–6 environment; particle and metal ion residues certified per customer spec.

Configurations & Options

• Geometry: OD 50–400 mm (larger on evaluation), long-length one-piece bodies; wall thickness optimized for strength/weight/heat flux.

• Ends & interfaces: flanges, bell-mouth, bayonet, locating rings, O-ring grooves, pump-out/pressure ports—tailored to your frames/jigs.

• Functional ports: thermocouple feedthrough preparation, sight window seats, bypass gas inlets (all with high-temp, leak-tight design).

• Coating strategies: inner wall (default), outer wall, or full coverage; local shielding/graded thickness for high-impingement zones.

• Surface & cleanliness: roughness grade, ultrasonic/DI clean, drying/bake curves configurable.

• Ancillaries: graphite/ceramic/metal flanges, seals, locating fixtures, handling sleeves and storage cradles.

Comparison

Frequently Asked Questions (FAQ)

Q1. Why monolithic 3D-printed SiC?
A. Eliminates seams/brazes that cause leaks and stress peaks; enables complex geometries with repeatable dimensions.

Q2. Will Cl-bearing gases attack SiC?
A. CVD SiC is highly inert to most Cl species within specified temperature/partial pressure/residence limits. Use local thickening in high-impingement zones and ensure robust purge/exhaust design.

Q3. What are the practical gains vs. quartz?
A. Longer life, better uniformity, lower particles/metal ions, and better TCO—especially above ~900 °C and in oxidizing/Cl environments.

Q4. Is fast ramping supported?
A. Yes, with controlled max ΔT and rates; pair high-κ body + thin coating, and follow first-use bake SOP.

Q5. When should a tube be retired?
A. Trigger on any of: flange/edge cracks, coating pits/spall, rising leak rate, drifted temperature profile, abnormal particle events.