Tungsten hexafluoride (WF₆) for ALD

Description

1. Product Overview

Tungsten Hexafluoride (WF₆) is the highest-purity tungsten precursor available for atomic layer deposition (ALD) and chemical vapor deposition (CVD), enabling nanoscale thin-film formation with exceptional uniformity. It is primarily used in semiconductor fabrication, specifically for tungsten metal film deposition in logic, memory, and advanced packaging. The key value proposition is its ability to deliver defect-free, conformal coatings at low temperatures (300–450°C), directly addressing the industry’s shift toward 3D device architectures. Strategically, securing a reliable, high-purity WF₆ supply is critical as global semiconductor capex surpasses $500B annually, with ALD becoming the dominant deposition method for nodes below 10nm.

2. Key Specifications & Technical Characteristics

• Chemical composition: Tungsten Hexafluoride (WF₆) ≥ 99.999% (5N)

• Purity grade: Semiconductor grade – 5N (99.999%) / Trace metal analysis available

• Physical characteristics:

  • Colorless gas at room temperature; liquefies under pressure

  • Molecular weight: 297.84 g/mol

  • Density (liquid at 20°C): ~3.44 g/cm³

  • Vapor pressure: ~60 kPa at 20°C

• Impurity control (typical, ppb level):

  • Mo, Fe, Cr, Ni, Na, K: <50 ppb each

  • H₂O, HF, O₂: <10 ppm

• Packaging options:

  • Stainless steel cylinders (47L, 440L, 940L)

  • Nickel-coated cylinders for ultrapure applications

  • ISO-compliant valve outlets (DISS 718 / CGA 660)

• Shelf life: 24 months from date of analysis when stored below 40°C in original sealed cylinder

3. Core Industrial Applications

• Semiconductors (Logic & Memory): Used in ALD/CVD for tungsten plug, word line, and contact layer deposition – outperforms sputtering with >99.5% step coverage on high-aspect-ratio structures (>20:1).

• 3D NAND & DRAM: Enables void-free fill of word lines and bit lines in vertical architectures, reducing electrical resistance by 30% compared to alternative refractory metals.

• Advanced Packaging (TSV): Tungsten liners for through-silicon vias using WF₆ achieve lower stress (under 500 MPa) than copper, eliminating delamination risk.

• Display & Photovoltaics: Select applications in thin-film transistors (TFTs) and barrier layers, where WF₆ provides superior corrosion resistance in humid environments.

Why better: Direct liquid injection (DLI) compatibility, no post-anneal required for low resistivity (8–15 µΩ·cm), and reduced particle generation (<0.02 particles/cm² at >10nm size).

4. Competitive Advantages

• Quality consistency: Lot-to-lot variability controlled within ±2% via real-time FTIR and ICP-MS; each cylinder ships with Certificate of Analysis (CoA) and traceability to raw material batch.

• Supply reliability: Dedicated manufacturing lines with >99.5% on-time delivery to Tier-1 fabs; dual-source feedstock strategy mitigates rare earth supply chain risk.

• Logistics capability: In-house ISO tank fleet and hazmat-certified logistics partners covering APAC, NA, EU within 5–7 days standard lead time.

• Price competitiveness: Volume-based tiered pricing and long-term agreements (LTA) with fixed escalation clauses – 12–18% below spot market average for contracts above 20MT/year.

• Sustainability: Zero-fluorine-emission returnable cylinder program and HF-neutralization service; compliant with EU F-Gas Regulation (517/2014) and REACH.

• Technical support: 24/5 process engineering support, on-site demo of ALD integration, and downloadable GDSII-level process recipes for leading OEM tools (ASM, TEL, Lam).

5. Commercial & Supply Information

• Minimum order quantity (MOQ): 10 kg (net weight) – equivalent to one 47L cylinder

• BULK 20MT loading capacity: 20 metric tons (net) = approximately 6,000 liters of liquefied gas – fits in one ISO tank container (20 ft)

• Loading density per 20 ft container: Standard container = 20 MT WF₆ net, using cryogenic ISO tank or 8 x 940L cylinders (manifolded)