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Hexafluoroethane

Hexafluoroethane (C₂F₆) is a synthetic perfluorocarbon compound, existing as a colorless, odorless, non-flammable gas at standard conditions, with high chemical stability and negligible solubility in water.^[1]^[2] It is relatively inert, nontoxic under normal exposure, though it poses an asphyxiation risk in confined spaces due to oxygen displacement.^[1]^[3] Produced primarily through electrochemical processes in aluminum smelting as a byproduct or via direct fluorination in chemical synthesis, hexafluoroethane finds key applications in semiconductor manufacturing for plasma etching of silicon dioxide and metal silicides, as well as in chamber cleaning and as a dielectric gas.^[1]^[4]^[5] Its thermal stability and low reactivity make it suitable for these high-precision processes, though emissions are regulated due to its classification as a potent greenhouse gas with an atmospheric lifetime exceeding 10,000 years and a global warming potential approximately 12,200 times that of carbon dioxide over 100 years.^[6]^[4] Despite its industrial utility, hexafluoroethane's environmental persistence has drawn scrutiny, contributing to radiative forcing in the atmosphere primarily from aluminum production and electronics fabrication sectors, prompting efforts in emission controls and alternative technologies.^[7]^[6] Limited medical uses, such as in ophthalmic procedures, highlight its biocompatibility, but overall deployment emphasizes containment to mitigate climate impacts.^[1]

Chemical and Physical Properties

Molecular Structure and Bonding

Hexafluoroethane possesses the molecular formula C₂F₆, comprising two carbon atoms linked by a single covalent bond, with each carbon atom bonded to three fluorine atoms, forming a perfluorinated ethane analog.^[1] This structure features sp³ hybridization at each carbon, resulting in tetrahedral geometry with bond angles near 109.5° and a preferred staggered conformation that aligns with D_{3d} point group symmetry.^[8] The symmetric arrangement cancels out individual C–F bond polarities, yielding a net dipole moment of zero and rendering the molecule nonpolar.^[9] The bonding in hexafluoroethane is dominated by robust σ-bonds, particularly the C–F linkages, which exhibit high dissociation energies—averaging approximately 475 kJ/mol—conferring exceptional thermal and chemical stability akin to other perfluorocarbons.^[10] This inertness stems from the electronegativity difference and strong overlap between carbon and fluorine orbitals, minimizing reactivity under standard conditions.^[1] Spectroscopically, the molecule is identifiable via infrared absorption bands primarily from C–F stretching vibrations between 1000 and 1400 cm⁻¹, as documented in gas-phase spectra.^[11] In ¹⁹F NMR, all six equivalent fluorine nuclei produce a single resonance signal, typically around -85 ppm relative to CFCl₃, underscoring the structural uniformity.^[12]

Thermophysical Characteristics

Hexafluoroethane is a colorless, odorless, and nonflammable gas at standard temperature and pressure conditions.^[1]^[3] It transitions from solid to liquid at a melting point of −100.6 °C and from liquid to gas at a boiling point of −26.3 °C under atmospheric pressure.^[1] The critical temperature, above which the substance cannot be liquefied regardless of pressure, is 19.7 °C.^[13] The gaseous density of hexafluoroethane at standard temperature and pressure (0 °C, 1 atm) is approximately 6.17 g/L, roughly five times denser than air, which can result in accumulation and oxygen displacement in low-lying or confined areas.^[14] Its solubility in water is negligible due to a low Henry's law constant, limiting aqueous dissolution to trace levels, whereas it demonstrates moderate to high solubility in organic solvents such as ethanol and ethers.^[15]^[16] Key thermodynamic properties include an isobaric heat capacity that increases with temperature and pressure, as measured in experimental data for pressurized conditions, and a thermal conductivity suitable for gas-phase heat transfer applications.^[17] These characteristics, derived from empirical measurements, support its behavior in processes involving phase changes or controlled thermal environments near ambient conditions.^[18]

Stability and Reactivity

Hexafluoroethane (C₂F₆) demonstrates exceptional chemical stability attributable to the high bond dissociation energies of its carbon-fluorine bonds, which exceed 485 kJ/mol, and the reinforced carbon-carbon bond strength compared to hydrocarbons, rendering the molecule highly resistant to thermal and chemical decomposition under ambient conditions.^[19]^[1] This inertness prevents reactivity with water, air, or common oxidizing agents at standard temperatures and pressures, with no rapid reactions observed in these environments.^[20] Safety data sheets from multiple suppliers confirm stability under recommended storage, though prolonged exposure to elevated temperatures may lead to container rupture due to pressure buildup rather than intrinsic chemical instability.^[21]^[22] The compound is non-flammable and exhibits no explosive properties in isolation, as it lacks the capacity to support combustion or form flammable mixtures under normal industrial conditions; extinguishing media are thus irrelevant for the gas itself, though surrounding fires require appropriate agents.^[22] Reactivity remains negligible with most substances, but violent interactions can occur with strong reducing agents, such as alkali metals, under specific forcing conditions.^[3] Decomposition typically requires high-energy inputs, such as plasma discharges or intense ultraviolet radiation, to cleave the robust C-F bonds, enabling controlled breakdown in specialized processes while underscoring its baseline non-reactivity.^[1] In the upper atmosphere, hexafluoroethane's photochemical stability—stemming from its resistance to photolysis by solar radiation—contributes to an estimated lifetime of 10,000 years, with minimal direct interactions with stratospheric ozone due to the absence of labile chlorine or bromine atoms present in chlorofluorocarbons.^[23] This persistence arises from first-principles bond strength considerations, where the electronegative fluorine shielding inhibits radical formation or chain reactions that would otherwise accelerate degradation.^[19] No hazardous polymerization or self-reactivity occurs, further affirming its utility in applications demanding chemical inertness.^[24]

Production and Historical Development

Synthesis Methods

Hexafluoroethane is primarily produced through the vapor-phase fluorination of hydrofluorocarbons with two carbon atoms, such as pentafluoroethane (CHF₂CF₃) or 1,1,1,2-tetrafluoroethane (CH₂FCF₃), using elemental fluorine gas (F₂).^[25] The reaction proceeds at temperatures of 250–500 °C and pressures of 0–3 MPa, with the hydrofluorocarbon fed at ≤6 mol% concentration relative to diluents like hydrogen fluoride or tetrafluoromethane to control exothermicity and reduce explosion hazards; fluorine-to-hydrofluorocarbon molar ratios range from 0.5:1 to 5:1, yielding hexafluoroethane via stepwise replacement of hydrogen atoms.^[25] Contact times of 0.1–120 seconds ensure high selectivity, minimizing perfluoropropane formation.^[25] An alternative route employs catalytic fluorination of pentafluoroethane with nitrogen trifluoride (NF₃) and nitrogen diluent over cobalt fluoride at 430 °C and 0.1 MPa, with gas space velocities of 2 min^-1, delivering a 79% yield based on gas chromatography analysis.^[26] This method leverages NF₃ as a fluorine source under controlled flow rates (e.g., 3.87 L/min NF₃, 2.58 L/min pentafluoroethane).^[26] Historically, hexafluoroethane arose as a byproduct from overfluorination during chlorofluorocarbon-115 (CF₃CHFCl) manufacturing processes prevalent in the 1960s–1970s.^[1] Direct fluorination of ethane (C₂H₆) with F₂ represents a foundational but less selective pathway, often requiring excess fluorine to achieve complete perfluorination.^[13] For electronic-grade hexafluoroethane demanding >99.999% purity, crude streams containing chlorine compounds (e.g., chlorodifluoroethane derivatives) are purified via fractional distillation under specific conditions to separate lower-boiling impurities, followed by adsorption on molecular sieves or activated carbon to eliminate trace hydrofluorocarbons and moisture.^[27]^[28] This multi-stage refinement ensures minimal contaminants that could affect reactivity in downstream applications.^[27]

Commercial Scale-Up and Key Milestones

Hexafluoroethane's commercial production began scaling in the 1980s, driven by its adoption in semiconductor manufacturing for plasma etching and chamber cleaning processes.^[29] Prior to 1990, fluorinated gas sales to the U.S. semiconductor sector, including hexafluoroethane, remained minimal at under 100 metric tons annually, constrained by limited wafer sizes and fabrication facilities.^[30] The 1990s marked a surge in production tied to the global semiconductor expansion, with hexafluoroethane emissions from plasma etching rising from roughly 200 metric tons per year in the early 1990s to 700 metric tons per year by the late decade, fueled by larger wafer diameters, increased cleanroom square footage, and higher etch rates in integrated circuit fabrication.^[1] This growth reflected a broader tripling of worldwide semiconductor production capacity, directly linking hexafluoroethane demand to advancements in microelectronics.^[30] Production and emissions centers shifted from U.S. and European dominance to Asia through the 2000s and 2010s, paralleling the relocation of semiconductor fabrication plants to lower-cost regions amid global supply chain reconfiguration.^[31] Post-2020 increases aligned with surging chip demand for artificial intelligence and data centers, evidenced by hexafluoroethane emission spikes in China from 2011 to 2021 that fully explained concurrent global atmospheric growth, with national outputs reaching levels equivalent to 78 million metric tons of CO₂ in 2021.^[32] These trends underscore hexafluoroethane's causal tie to high-tech sector expansion rather than diversified applications.^[32]

Industrial Applications and Economic Role

Semiconductor Etching and Cleaning

Hexafluoroethane (C₂F₆) functions primarily as a fluorocarbon source gas in plasma-based reactive ion etching (RIE) processes during semiconductor fabrication, where it dissociates to produce atomic fluorine radicals for the anisotropic removal of dielectric layers such as silicon dioxide (SiO₂) and silicon nitride (Si₃N₄).^[33]^[5] This application is integral to defining sub-micron features in integrated circuits, as the high fluorine-to-carbon ratio (3:1) yields aggressive yet controllable etch rates, facilitating vertical profiles with minimal lateral undercutting.^[33]^[34] In plasma-enhanced chemical vapor deposition (PECVD) and chemical vapor deposition (CVD) chamber maintenance, C₂F₆ mixed with oxygen (C₂F₆/O₂) cleans accumulated SiO₂ and Si₃N₄ residues from reactor walls and components, preventing particle contamination and maintaining process uniformity across wafer batches.^[35]^[36] These cleaning cycles, often conducted via inductively coupled plasma (ICP) or remote plasma sources, ensure high yield in subsequent deposition steps by restoring chamber conditions without mechanical intervention.^[37] Relative to nitrogen trifluoride (NF₃), C₂F₆-based plasmas exhibit superior selectivity in certain ICP-RIE scenarios, such as etching Ge-doped SiO₂ or sapphire substrates, where process parameters like RF power and pressure can be adjusted to enhance anisotropy and material-specific etch rates while preserving underlying layers like polysilicon.^[38]^[39]^[40] This tunability supports high-aspect-ratio structures in back-end-of-line (BEOL) interconnects, critical for advanced nodes like 5 nm, where multiple etch steps demand precise control to achieve feature densities aligned with scaling trends.^[33]^[36] The precision enabled by C₂F₆ etching underpins the $701 billion global semiconductor industry in 2025, powering density improvements that advance computing performance, electric vehicle power electronics, and defense-grade microelectronics.^[41]^[42]

Leak Detection and Other Specialized Uses

Hexafluoroethane functions as a tracer gas in leak detection for refrigeration systems, where it is introduced into the refrigerant circuit to enable identification of breaches via specialized sensors, facilitating rapid repairs and minimizing system downtime.^[43] This method leverages the compound's chemical stability and non-reactivity, allowing precise localization of leaks without contaminating the primary refrigerant.^[43] In pipeline and containment integrity testing, hexafluoroethane is deployed to detect micro-leaks in high-pressure systems, particularly benefiting sectors requiring stringent safety protocols by curtailing environmental releases and operational interruptions.^[44] Its inert properties ensure compatibility with diverse materials, supporting applications in pressurized conduits where traditional tracers like helium may prove less suitable due to diffusion rates or cost factors.^[44] Beyond leak tracing, hexafluoroethane finds niche employment as a tamponading agent in vitreoretinal surgery, substituting vitreous humor to stabilize retinal detachments post-vitrectomy, owing to its physiological inertness and expandability under pressure.^[45] It also serves as a minor additive in select plasma processes for its etching selectivity, though volumes remain low relative to bulk uses.^[46] Market analyses indicate that electronic-grade hexafluoroethane, typically ≥99.9% purity, commands the largest demand share, exceeding standard grades due to requirements in precision environments, with projections for sustained growth through 2025 amid clean room and high-tech integrations.^[47]^[48] Specialty formulations for such controlled settings represent a targeted subset, emphasizing ultra-high purity to avert contamination in sensitive operations.^[47]

Contributions to Technological Advancement

Hexafluoroethane (C2F6) plays a critical role in plasma etching processes for semiconductor fabrication, enabling the precise removal of dielectric layers such as silicon dioxide with high etch rates and selectivity to underlying materials. This capability is essential for patterning features at nanometer scales in advanced logic and memory chips, which underpin technologies including artificial intelligence accelerators, photovoltaic inverters for renewable energy systems, and imaging sensors in medical devices. The fluorine radicals generated from C2F6 dissociation facilitate volatile byproduct formation, achieving etch rates that support high-volume production yields necessary for scaling Moore's Law-like progress in transistor density.^[36] Alternatives to C2F6, such as non-fluorinated or hydrofluorocarbon-based gases, often result in reduced etch efficiencies; for instance, comparative studies show etch rate drops of approximately 50% when substituting compounds like carbonyl fluoride (COF2) for nitrogen trifluoride (NF3), a common C2F6 replacement in chamber cleaning. Such inefficiencies would extend fabrication cycle times, elevate defect rates, and constrain the economic viability of producing chips below 5 nm nodes, thereby impeding advancements in computational power for AI training and energy-efficient electronics. From a causal standpoint, the chemical inertness and bond strength of C2F6-derived fluorocarbons provide unmatched anisotropy in reactive ion etching, where less effective substitutes fail to maintain sidewall profiles critical for interconnect reliability.^[49] While C2F6 possesses a high global warming potential, its deployment in semiconductors involves low per-wafer volumes, with perfluorocarbon emissions from the sector constituting less than 0.2% of U.S. total greenhouse gases and a similarly minor share globally relative to dominant sources like fossil fuel combustion. Substitutes such as NF3, though sometimes favored for shorter atmospheric lifetimes, introduce parallel trade-offs including comparable global warming impacts and challenges in complete decomposition during use. Overly stringent phase-outs risk exacerbating technological disparities, as evidenced by China's semiconductor expansion driving near-total global increases in CF4 and C2F6 emissions since 2010, while regulated regions like the U.S. and EU face potential constraints on domestic fabrication capacity.^[50]^[51]^[32]^[52]

Environmental Considerations

Atmospheric Lifetime and Global Warming Potential

Hexafluoroethane exhibits an atmospheric lifetime of approximately 10,000 years, reflecting its exceptional chemical inertness, which resists degradation by common tropospheric oxidants like hydroxyl radicals and ozone, with primary removal via slow stratospheric photolysis.^[32]^[4] This persistence far exceeds that of most anthropogenic greenhouse gases, rendering natural sinks effectively negligible on timescales relevant to human activity or climate policy.^[31] The compound's 100-year global warming potential stands at 12,200 relative to CO₂, a metric derived from its radiative efficiency and longevity, as quantified in IPCC assessments incorporating empirical spectroscopic data and atmospheric modeling.^[53]^[54] Radiative efficiency, approximately 0.5 W m⁻² ppb⁻¹, arises from strong infrared absorption bands primarily between 600 and 1400 cm⁻¹, associated with C–F vibrational modes that overlap key atmospheric transmission windows, though the molecule's high symmetry moderates per-molecule forcing compared to asymmetric fluorocarbons.^[55] Empirical radiative forcing from hexafluoroethane remains minimal, on the order of 10⁻³ W m⁻² at observed global mixing ratios under 10 ppt, underscoring that climate impacts hinge causally on emission scales rather than intrinsic potency alone; absent substantial industrial releases, contributions to net forcing are inconsequential relative to dominant gases like CO₂.^[56]^[57] Model-based extrapolations confirm this, prioritizing concentration-driven effects over exaggerated per-unit alarm.^[7]

Emission Sources and Global Trends

The primary sources of hexafluoroethane (C2F6) emissions are industrial processes in semiconductor manufacturing, where it is used as a precursor in remote plasma cleaning of reaction chambers, resulting in unintentional releases primarily from incomplete destruction in abatement systems rather than deliberate venting; these account for the majority of emissions globally.^[30] Aluminum smelting contributes secondarily as an unintentional by-product during anode effects, while fugitive leaks from storage and handling remain minor.^[58] ^[59] Global emissions of C2F6 are estimated at approximately 2.2 Gg per year as of 2020, with East Asia—particularly semiconductor production hubs in China, Taiwan, South Korea, and Japan—accounting for roughly 70% of the total, reflecting the region's dominance in electronics fabrication driven by surging chip demand.^[58] ^[59] Atmospheric monitoring by the Advanced Global Atmospheric Gases Experiment (AGAGE) network reveals a steady rise in C2F6 concentrations post-2010, with growth rates accelerating in the 2010s, consistent with expanded semiconductor output rather than shifts in emission controls.^[59] A pronounced spike in emissions from China during the 2020s, rising from 0.74 Gg in 2011 (38% of global total) to 1.32 Gg in 2021 (64% of global total)—a 78% increase—fully accounts for observed global atmospheric growth exceeding 100% over the decade, attributed to rapid expansion in both aluminum production capacity and semiconductor facilities in eastern provinces.^[58] This trend aligns with AGAGE-inverted emission estimates showing East Asian C2F6 outputs increasing by 0.29 Gg per year from 2012–2014 to 2017–2019.^[59] Overall global emissions have trended upward at 15% over similar periods, underscoring causal linkages to industrial scaling in high-tech sectors.^[59]

Regulatory Frameworks and Mitigation Strategies

Hexafluoroethane, classified as perfluorocarbon PFC-116, was included among the greenhouse gases targeted for emission reductions under the Kyoto Protocol, which entered into force on February 16, 2005, and required Annex I parties to limit emissions of hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride alongside the primary gases.^[60] In the United States, the Environmental Protection Agency established mandatory reporting of greenhouse gas emissions, including C₂F₆ from semiconductor manufacturing and aluminum production processes, under 40 CFR Part 98 Subpart I, with the rule finalized on October 30, 2009, applying to facilities exceeding 25,000 metric tons of CO₂ equivalent annually.^[61] The European Union's F-Gas Regulation (EU) No 517/2014, updated by Regulation (EU) 2024/573 effective March 11, 2024, imposes phase-down schedules primarily on hydrofluorocarbons but extends monitoring, leakage prevention, and containment requirements to other fluorinated gases like perfluorocarbons, promoting shifts to alternatives with lower global warming potentials through quotas and prohibitions on high-GWP uses in refrigeration and foams.^[62] Mitigation strategies emphasize technological interventions over outright bans, with point-of-use destruction systems such as plasma abatement achieving destruction removal efficiencies exceeding 99% for C₂F₆ in semiconductor exhaust streams by generating high-temperature reactive species that decompose the molecule into less harmful byproducts like HF and CO₂.^[63] Recycling approaches involve capture and purification loops to reclaim unreacted hexafluoroethane from process tools, reducing net emissions by reinjecting recovered gas, though implementation requires vacuum-compatible systems to maintain purity above 99%.^[64] Ongoing research into substitutes, such as fluorinated ethers or nitrogen trifluoride for etching applications akin to those using C₂F₆, faces scalability challenges due to performance gaps in etch rates and selectivity, limiting widespread adoption.^[65] Regulatory pressures in developed nations have prompted concerns over emission leakage, as stringent controls correlate with offshoring of semiconductor and electronics manufacturing to jurisdictions like China, where PFC-116 emissions surged substantially from 2011 to 2020 amid rapid industry expansion, potentially offsetting global reductions.^[66] Empirical data from abatement deployments indicate 50-90% reductions in C₂F₆ emissions without prohibitive restrictions, as process optimizations and plasma systems yield verifiable decreases in facilities adopting them, underscoring the efficacy of innovation-driven approaches over relocation risks.^[67]^[65]

Health, Safety, and Risk Assessment

Acute and Chronic Exposure Effects

Hexafluoroethane acts primarily as a simple asphyxiant upon inhalation at concentrations exceeding 30% by volume, where it displaces oxygen in confined spaces, potentially leading to dizziness, unconsciousness, or death due to hypoxia.^[68] ^[21] Acute inhalation toxicity is low, with an LC50 value greater than 282,000 ppm (1-hour exposure in rats), indicating minimal inherent toxic effects beyond oxygen displacement.^[69] Direct contact with the cryogenic liquid form can cause frostbite, while exposure to vapor or liquid may result in mild to severe, reversible irritation or burns to skin and eyes, with possible transient damage.^[68] ^[24] No evidence of systemic toxicity, carcinogenicity, or mutagenicity has been identified in regulatory assessments, with hexafluoroethane not classified as a carcinogen by OSHA, IARC, or NTP, and germ cell mutagenicity criteria not met based on available data.^[24] ^[70] ^[71] Chronic exposure effects are negligible, as the compound's chemical inertness prevents significant metabolism, bioaccumulation, or organ damage in animal studies and human handling contexts.^[21] ^[72] Adverse chronic symptoms are not expected under typical occupational exposure levels.^[73]

Occupational Handling Protocols

Hexafluoroethane, a non-flammable compressed gas and simple asphyxiant, necessitates robust ventilation protocols during occupational handling to avert oxygen displacement in work environments. Engineering controls such as local exhaust ventilation or general dilution ventilation are required to maintain airborne concentrations below levels that could reduce oxygen below 19.5% by volume, with particular emphasis in confined spaces where the gas's higher density promotes accumulation at floor level.^[21] Continuous oxygen monitoring using calibrated detectors is mandatory prior to and during entry into such spaces, as per standard protocols for asphyxiant gases, to detect deficiencies that could lead to rapid unconsciousness without warning due to the gas's odorless and non-irritating nature.^[68] Personal protective equipment for handling includes insulated gloves, face shields, and full-body protective suits to mitigate cryogenic hazards from liquid or expanding cold gas, which can cause frostbite or thermal burns upon skin contact.^[21] Self-contained breathing apparatus or supplied-air respirators are advised when ventilation proves inadequate or during leak response, alongside safety goggles to protect against cylinder valve failures or splashes in pressurized systems.^[24] Storage protocols dictate securing cylinders in upright positions within cool, well-ventilated areas away from ignition sources and compatible materials, using pressure-rated equipment compatible with fluorinated gases to prevent rupture or decomposition.^[21] The NFPA 704 rating classifies it as Health: 1 (slight hazard from asphyxiation under misuse), Flammability: 0 (non-combustible), and Reactivity: 1 (stable but pressure-sensitive), underscoring the need for valve protection caps and periodic integrity checks.^[74] Training programs for personnel emphasize recognition of asphyxiation risks, proper cylinder manipulation, and emergency shutdowns, including the ironic utility of hexafluoroethane as a tracer gas in leak detection for semiconductor and refrigeration systems—where its deployment identifies breaches that could release more toxic etchants or refrigerants, thereby averting broader industrial incidents.^[21] Post-handling hygiene involves thorough handwashing and prohibiting eating or smoking in exposure areas to minimize incidental ingestion of residues.^[72]

Comparative Risk Evaluation

The climatic impact of hexafluoroethane (C2F6) emissions, while notable per molecule due to its 100-year global warming potential (GWP) of 12,200 relative to CO2, remains marginal in global radiative forcing terms. Anthropogenic C2F6 contributed approximately 7.5 × 10^{-4} W/m² to forcing as of 2001, dwarfed by CO2's total anthropogenic forcing exceeding 2 W/m², much of which stems from transportation sectors emitting over 8 GtCO2 annually. Even at peak semiconductor industry usage, C2F6 volumes yield forcing contributions orders of magnitude below routine CO2 sources like vehicle exhaust, underscoring that low-probability leakage events do not causally dominate net warming relative to ubiquitous combustion emissions. Health and safety risks from C2F6 exposure are primarily asphyxiation via oxygen displacement in confined spaces, with no documented direct fatalities or major industrial accidents attributed to the compound itself in occupational records.^[68]^[1] This contrasts with higher-incidence hazards in everyday activities, such as traffic accidents claiming millions annually, while C2F6 enables semiconductor etching for reliable electronics that enhance system safety—e.g., error-reducing microchips in vehicles and medical devices—yielding net societal risk reductions. Alternatives like nitrogen trifluoride (NF3), increasingly used in chamber cleaning and etching, exhibit a higher GWP of 17,200 and, despite better plasma utilization efficiency (reducing emissions per process by up to 89% in some tools), often result in greater per-etch-volume climate forcing when scaled to equivalent output.^[30]^[75] Restrictive policies targeting C2F6 overlook these trade-offs and broader benefits, including advanced computing's role in optimizing energy use across sectors—e.g., efficient chips lowering data center demands that otherwise rival small nations' power consumption—thus amplifying indirect emissions savings far exceeding direct PFC releases.^[36]^[65] Narratives framing PFCs as "super greenhouse gases" frequently exaggerate impacts by ignoring emission volumes and process efficiencies, per industry analyses.^[75]

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Introduction to Electronic Gas Etching - Yuji America
Sep 13, 2024 · In the dry etch process, fluorinated gases commonly used are sulfur hexafluoride (SF6), tetrafluoromethane (CF4), and hexafluoroethane (C2F6).
[35]
Global warming gas emission during plasma cleaning process of ...
An alternative c-C4F8O-based cleaning chemistry for the silicon nitride PECVD chamber was evaluated as a potential replacement for C2F6 /O2 cleaning chemistry ...
[36]
[PDF] Semiconductor PFAS Consortium Plasma Etch and Deposition
Jun 28, 2023 · This publication was developed by the Semiconductor PFAS Consortium plasma etch and deposition technical working group.
[37]
Remote plasma etching of silicon nitride and silicon dioxide using ...
The etching characteristics of fluorocarbon gases like CF4 and C2F6 have been widely studied. These gases are used for reactor cleaning, but since etching often ...<|control11|><|separator|>
[38]
Inductively coupled plasma reactive ion etching of sapphire using C ...
In this paper, ICP-RIE characteristics of sapphire films were investigated as a function of various process variables, using C 2 F 6 - and NF 3 -based gases.
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[PDF] Silicon Dioxide to Polysilicon Selectivity of a C2F6/CHF3 Dry Etch ...
The balance between selectivity and anisotropy can be controlled by changing the power and pressure of the plasma. ~ the chamber pressure is decreased or the ...
[40]
Inductively coupled plasma reactive ion etching of Ge-SiO2 and ...
May 3, 2025 · Inductively coupled plasma reactive ion etching of Ge doped silica glasses and SiON was investigated, using C2F6- and NF3-based gas mixtures.Missing: advantages | Show results with:advantages
[41]
WSTS Semiconductor Market Forecast Spring 2025
Following a strong rebound in 2024, the global semiconductor market is projected to expand by 11.2% in 2025, reaching a total value of $700.9 billion. · While ...
[42]
2025 State of the Industry Report: Investment and Innovation Amidst ...
Jul 10, 2025 · Estimates from the World Semiconductor Trade Statistics (WSTS) project that worldwide semiconductor industry sales will increase to $701 billion ...
[43]
US5149453A - Method for detecting leakage in a refrigeration system
This invention relates to a leak detection composition and method for use with air conditioning and other refrigeration systems. ... hexafluoroethane/ ...
[44]
Hexafluoroethane C2F6-76-16-4 in the Real World: 5 Uses You'll ...
Sep 20, 2025 · Its inert nature ensures no chemical reactions occur during operation, reducing maintenance needs and downtime.
[45]
MICROGAS C2F6 MIXED - Micromed
It is a high molecular weight gas used in vitrectomy, ab-external surgery, and pneumatic retinopexy. The product is intended to replace the vitreous humor and ...
[46]
Hexafluoroethane - an overview | ScienceDirect Topics
Hexafluoroethane is defined as a colorless, nontoxic, and thermally stable compound that can be a pyrolysis product of liquid perfluoro-n-alkanes, particularly ...
[47]
Hexafluoroethane C2F6-76-16-4 Market Size And Forecast
Rating 4.5 (49) Hexafluoroethane C2f6-76-16-4 Market size is projected to reach USD 352.24 Million by 2032,growing at a CAGR of 4.6% during the forecast period 2026-2032.
[48]
Electronic Special Hexafluoroethane (C2F6) 2025-2033 Analysis
Rating 4.8 (1,980) May 6, 2025 · The C2F6 market is characterized by a few key trends. Firstly, increasing demand from advanced semiconductor manufacturing drives growth, ...Missing: milestones | Show results with:milestones
[49]
[PDF] Background on Semiconductor Manufacturing and PFAS
May 17, 2023 · Over the past three decades, the semiconductor industry has experienced rapid growth and delivered enormous global economic impact. Chip ...
[50]
The time is now: sustainable semiconductor manufacturing - USA
Semiconductor manufacturing is a minor contributor to GHG emissions. For example, in the US in 2015, it accounted for 0.18 % of total greenhouse gas (GHG) ...Missing: percentage | Show results with:percentage
[51]
Chip Production's Ecological Footprint: Mapping Climate and ...
Jun 20, 2024 · Manufacturing accounts for 74% of all emissions, with semiconductors alone responsible for half of their GHG emissions from electronic ...
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Projected increases in emissions of high global warming potential ...
Jun 8, 2023 · We find that total emissions of fluorinated greenhouse gases from China are projected to increase to 506–1356 million tons CO 2 -equivalent per year in 2060 if ...
[53]
[PDF] IPCC Global Warming Potential Values - GHG Protocol
Aug 7, 2024 · The use of the latest values (AR6) is recommended. IPCC also publishes 20-year and 500-year time horizon GWPs but these are not included in this ...
[54]
Global warming potential - Clean Energy Regulator
Mar 22, 2024 · Summary of updates to GWP values ; Perfluoroethane (hexafluoroethane), 9,200, 12,200, 11,100, –9% ; Sulphur hexafluoride, 23,900, 22,800, 23,500 ...
[55]
The Infra‐Red Absorption Spectrum of Hexafluoroethane Gas
The infra‐red absorption of gaseous hexafluoroethane between 2 and 25μ has been investigated with prism spectrometers of high resolution. On the basis of ...Missing: NMR | Show results with:NMR
[56]
Atmospheric trends and radiative forcings of CF4 and C2F6 inferred ...
Apr 1, 2007 · The radiative forcings of CF4 and C2F6 are shown to have increased over the past 50 years to values in 2001 of 4.1 x 10(-3) Wm(-2) and 7.5 x 10 ...Missing: efficiency | Show results with:efficiency
[57]
Perfluorocarbons in the global atmosphere: tetrafluoromethane ...
Jun 9, 2010 · We present atmospheric baseline growth rates from the 1970s to the present for the long-lived, strongly infrared-absorbing perfluorocarbons ( ...Missing: efficiency | Show results with:efficiency
[58]
Substantial increase in perfluorocarbons CF4 (PFC-14) and C2F6 ...
Jul 15, 2024 · We investigate the emissions of two potent greenhouse gases, perfluorocarbons tetrafluoromethane (CF4, PFC-14) and hexafluoroethane (C2F6, ...
[59]
Emissions of Tetrafluoromethane (CF4) and Hexafluoroethane ...
Aug 6, 2021 · In this study, we estimate emissions of CF4 and C2F6 from East Asia, where PFC emitting industries are heavily concentrated, using a top-down ...Missing: photochemical | Show results with:photochemical
[60]
How to make Kyoto a success - Nature
Oct 23, 1997 · ... (PFCs) tetrafluoromethane (CF4) and hexafluoroethane (C2F6) released mainly during industrial production of aluminium and semiconductors.
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Mandatory Reporting of Greenhouse Gases - Federal Register
Oct 30, 2009 · On April 10, 2009 (74 FR 16448), EPA proposed the GHG reporting rule. EPA held two public hearings, and received approximately 16,800 written ...Missing: C2F6 | Show results with:C2F6
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[PDF] Regulation (EU) 2024/573 of the European Parliament ... - EUR-Lex
Feb 20, 2024 · an HFC phase-down that is to reduce HFC production and consumption ... F-gas Portal via the EU Single Window Environment for Customs. 6 ...
[63]
Universal Plasma Abatement System - Air Liquide Electronics Systems
> Destroys +99% of PFCs* molecules, such as hexafluoroethane (C2F6), octafluoropropane (C3F8), octafluorocyclobutane (C4F8), fluoroform (CHF3), nitrogen ...
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Environmental Impact of PFC Abatement, Capture and Recycle
The tradeoffs between abatement, capture, recycling, and replacements of PFCs are complex and directly influence cost of ownership. These tradeoffs are ...Missing: mitigation | Show results with:mitigation
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Perfluorocompounds emission reduction by the semiconductor ...
The semiconductor industry is an extremely minor contributor to the overall emissions of greenhouse gases (GHGs) by sector. Based on 2006 European Union GHG ...Missing: rise | Show results with:rise<|control11|><|separator|>
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Substantial increase in perfluorocarbons CF 4 (PFC-14) and ... - PNAS
It is likely that the aluminum industry dominates CF4 emissions in China, while the aluminum and semiconductor industries both contribute to C2F6 emissions.
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https://www.unfccc.int/sites/default/files/wamatt006_1.pdf
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[PDF] Hexafluoroethane - NJ.gov
HAZARD SUMMARY. * Hexafluoroethane can affect you when breathed in. * Contact can cause severe skin and eye irritation and burns with possible eye damage.
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Halocarbon 116 C2F6 Safety Data Sheet SDS P4670
Acute toxicity. : Not classified. Hexafluoroethane (R116) ( \f )76-16-4. LC50 inhalation rat (ppm). 282843 ppm/1h. Hexafluoroethane (76-16-4). LC50 inhalation ...
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[PDF] Safety Data Sheet - EFC Gases & Advanced Materials
EF-016 - Hexafluoroethane. Revision Date: 24-Jun-2024. Page 4 / 7. 9. PHYSICAL AND CHEMICAL PROPERTIES. Information on basic physical and chemical properties.Missing: impact | Show results with:impact
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[PDF] SAFETY DATA SHEET Hexafluoroethane (R116) SECTION 1
Jan 20, 2017 · Signal Words: Warning. Hazard Statement(s):. H280: Contains gas under pressure; may explode if heated. Precautionary Statement. Prevention: None ...
[72]
[PDF] Hexafluoroethane - Synquest Labs
Information on toxicological effects. Acute toxicity (oral). : Not classified. Acute toxicity (dermal). : Not classified. Acute toxicity (inhalation). : Not ...
[73]
[PDF] Hexafluoroethane (R116) - MsdsDigital.com
Sep 7, 2016 · Acute toxicity. : Not classified. Hexafluoroethane (R116) (76-16-4) ... Chronic symptoms. : Adverse effects not expected from this product.
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[PDF] HEXAFLUOROETHANE (R-116) - Safety Data Sheet
Jun 1, 2015 · Section 10: Stability and Reactivity. Stability. Conditions to Avoid. Incompatible Materials. Stable under recommended storage conditions.
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The Greenhouse Gas That Nobody Knew - Yale E360
Nov 13, 2008 · The usual choice, hexafluorethane, or C2F6 sounds better at first than NF3. ... NF3 was a niche product of unknown global warming potential (GWP).