Hexafluorobutadiene (C₄F₆) — The "Etching Scalpel" for 3D NAND and HBM Manufacturing

Applications and Uses

Hexafluorobutadiene (C₄F₆) is an irreplaceable etching gas for 14nm and below advanced logic processes, 3D NAND (300 layers and above), and HBM high-bandwidth memory. It enables deep trench vertical etching with high aspect ratios — a critical requirement for modern memory and logic chips. Traditional etching gases such as CF₄ and C₄F₈ can be used for mature process NOdes, but advanced nodes have no alternative to C₄F₆. As AI chips continue to increase layer counts and HBM expands capacity, the demand for C₄F₆ becomes increasingly inelastic.

Market Conditions and Shifts

The price trajectory of C₄F₆ in 2026 illustrates the severity of the supply-demand imbalance. At the beginning of 2026, high-purity products traded at approximately RMB 2.2 million/ton. By mid-year, spot prices had soared to RMB 3.0–3.8 million/ton, with紧缺 supplies reaching as high as RMB 4.0 million/ton. In July, long-term contract prices for major customers (accounting for 90% of market shipments) reached RMB 3.95–4.75 million/ton, with spot and urgent orders reaching RMB 4.5–4.8 million/ton and extreme cases hitting RMB 4.9 million/ton.

The supply side is highly concentrated. Japan's Kanto Denka has significantly reduced exports to China in 2026, while Germany's Linde supplies primarily to European and American markets. Among domestic producers, Haohua Technology is the only company with stable 5N mass production and full certification from leading customers. Other producers — including Zhongchuan Special Gas (200 tons/year), Huate Gas (300 tons/year under construction, expected completion July 2026), Jinhong Gas (200 tons/year planned), and Juxin (175 tons/year completed) — are mostly in certification or small-batch stages.

Technology Transition: From Legacy Gases to C₄F₆

The semiconductor industry's transition from planar transistors to 3D structures has fundamentally changed etching gas requirements. Traditional etching gases such as CF₄ and C₄F₈ are adequate for planar processes but cannot achieve the high aspect ratio, vertical sidewall profiles required for 3D NAND and advanced logic. C₄F₆ offers superior etching selectivity, higher etch rates, and cleaner decomposition products — making it the only viable option for deep trench etching in advanced nodes. With new capacity additions requiring 1.5–2 years for construction and customer certification, the global C₄F₆ supply gap of over 40% is expected to persist through 2026.