Scope 1 Semiconductor Etch Gases Calculator (CF4 / C2F6 / NF3 / SF6 PFC Emissions — IPCC Vol 3 Ch 6)
Compute the Tier 1 process CO2e from the fluorinated etch and chamber-clean gases used in chip, display, and solar manufacturing — substrate area times the IPCC 2006 default factor for each gas, weighted by its global-warming potential and summed.
High-warming gases, by area. The Scope 1 process emissions of electronics manufacturing come from fluorinated compounds — CF4, C2F6, CHF3, C3F8, NF3, and SF6 — used to etch circuits and clean deposition chambers. A fraction of each gas escapes unreacted. This calculator computes that escape as substrate area processed multiplied by the IPCC 2006 default factor for each gas, as set out in Volume 3, Chapter 6. These are the highest-warming gases in routine industrial use: SF6 warms the climate 25,200 times as much as CO2.
The gas mix is the story. Because the global-warming potentials of these gases span thousands to tens of thousands, the headline is driven by which gas is used, not how much. A few grams of SF6 can outweigh kilograms of CF4. The calculator reports the CO2e contribution of each gas so the dominant one — usually the one to abate first — is visible.
Two tiers, and abatement is live. Tier 1 takes the gross default factor by substrate area. Tier 2 is the gas-by-gas mass balance that credits the gas destroyed in the process and in any installed abatement — using your fab’s own utilisation and destruction figures, since IPCC publishes no facility defaults for them. The tool carries both.
AR5 by default, AR6 on toggle. The basis matters here more than on any other process calculator, because the gases are so potent: moving from AR5 to AR6 shifts the total by around a tenth. The default is AR5, matching most disclosure regimes; AR6 is a toggle.
Tier 1: substrate area → default gas set. Tier 2: per-gas FC × (1 − U) × (1 − a·d).
AR5↔AR6 drift is material for F-gases — confirm your framework’s GWP set.
Tier 1 default factors per IPCC Vol 3 Ch 6 Table 6.2. Pick a manufacturing segment and enter substrate area consumed; the complete gas set for that segment is computed.
Annualised: result × (12 ÷ period months).
Audit mode exposes the full per-line factor chain.
Add a ledger line above to calculate
Results appear instantly. The per-gas CO₂e split, breakdown table, IPCC uncertainty disclosure, and full audit trail appear after calculation.
Results are indicative Scope 1 process-emission estimates for electronics manufacturing fluorinated compounds (plasma etch, CVD chamber-clean, and heat-transfer-fluid loss) using IPCC 2006 Vol 3 Ch 6. Tier 1 substrate-area default factors carry wide IPCC uncertainty — skewed toward zero, up to +200% (95% CI) — and will differ from measured fab-specific (Tier 2/3) data; use Tier 2 with your own gas-purchase, utilisation, and abatement (DRE) data where available. The result covers direct process F-gas emissions only; it excludes Scope 2 fab electricity, Scope 3 gas supply, and N₂O. PV-cell lines apply the IPCC §6.2.3 default C_PV = 0.5 (fraction of PV manufacture using FCs); CHF₃ is weighted with the HFC-23 GWP. Confirm gas, utilisation, and abatement data against your own records and, where material, proceed to third-party verification under ISO 14064-3.
In a chip fab’s emission inventory, ten tonnes of one gas can outweigh forty-five tonnes of another. The lighter line is sulphur hexafluoride; the heavier one is tetrafluoromethane. The difference is not mass — it is that one molecule of SF6 traps as much heat as twenty-five thousand molecules of CO2.
For electronics process emissions, the question is never how much gas. It is which gas.
The semiconductor etch gases calculator multiplies substrate area processed by IPCC 2006 default factors for six fluorinated gases — CF4, C2F6, CHF3, C3F8, NF3, SF6 — and weights each by its global-warming potential to give Tier 1 Scope 1 CO2e, with a Tier 2 mass balance that credits abatement.
What the semiconductor etch gases calculator does
This calculator computes the Tier 1 Scope 1 process emissions of electronics manufacturing: the fluorinated gases that escape unreacted from plasma etching and chamber cleaning. You enter the substrate area processed for a segment — silicon wafers, display glass, or solar cells — and the engine multiplies by the IPCC 2006 default factor for each gas that segment uses, weights it by global-warming potential, and sums the gases into one CO2e total.
Process F-gas emissions from etch and chamber-clean
The emission here is a process emission, not an energy one. Fluorinated compounds are fed into plasma tools to etch fine features into silicon and to clean the residue from deposition chambers. Much of the gas reacts, but a fraction passes through unconsumed and escapes to atmosphere — that escaped fraction is the emission. It has nothing to do with the electricity or fuel that powers the fab; those are separate energy emissions under a different inventory. What this tool captures is the fluorinated gas itself, which because of its extreme warming potential is often the largest part of a fab’s direct climate impact despite tiny mass.
Six gases, four segments, two tiers
The calculator models six gases — CF4, C2F6, CHF3, C3F8, NF3, and SF6 — across four manufacturing segments: integrated-circuit fabs, flat-panel displays, photovoltaic cells, and the heat-transfer fluids used to cool process equipment. Each segment uses a different subset of the gases on a different substrate basis. And each line can be computed at Tier 1, the gross default, or Tier 2, the abatement-aware mass balance. The sections below take each of these in turn.
This is a process-emissions tool for fluorinated gases, not an energy tool. The CO2e here is the unreacted etch and chamber-clean gas escaping under IPCC Vol 3 Ch 6 — measured per square metre of substrate processed, not per tonne of product. The fab’s electricity, which is usually large, is a separate Scope 2 line outside this boundary.
Why the gas matters more than the quantity
These six gases are the most potent in routine industrial use. Their global-warming potentials run from thousands to tens of thousands of times that of CO2, which means the emitted mass tells you almost nothing about the climate impact on its own. The gas with the largest CO2e contribution is frequently not the one emitted in the largest quantity — and identifying which gas dominates is the single most useful thing this calculator does.
The chart below shows the CO2e contribution of each gas in a worked integrated-circuit fab inventory (detailed in full later). It is the clearest illustration of the leverage effect: C2F6 and CF4 lead on a mix of mass and potency, while SF6 reaches a fifth of the total from only ten tonnes of emitted gas — because its warming potential is so high. CHF3 and C3F8 stay trace despite being present.
CO2e contribution by gas for the worked IC-fab inventory (1,167,600 t CO2e, AR5 basis; 50,000 m² silicon). Bar widths proportional to each gas’s CO2e. SF6 reaches 20% from ten tonnes of emitted mass because its GWP is 23,500; the top three gases are 93% of the total. Values reconcile vs MasterBrain v2026.203.
A gram of SF6 outweighs twenty-five kilograms of carbon dioxide. In an electronics inventory the emitted mass is a distraction — the warming potential is the number that decides which gas matters and which to abate first.
Why the AR5/AR6 choice is load-bearing here
On most process calculators the choice between the AR5 and AR6 global-warming-potential sets barely moves the total. Here it is material, because these gases were revised more than most between the two IPCC assessments. NF3 rises about 8% from AR5 to AR6, C2F6 about 12%, and CHF3 about 18%; the worked inventory above rises around 10.6% overall. The calculator defaults to AR5, which matches the GHG Protocol and most current disclosure regimes, and offers AR6 as a toggle. Set the basis to match the rest of your inventory and do not mix the two.
The result tracks the gas mix, not the gas quantity. Because these GWPs span thousands to tens of thousands, the dominant CO2e gas is rarely the one emitted in greatest mass — SF6 proves it, reaching a fifth of the worked total from a tenth of the emitted tonnage. Read the per-gas contribution, and pick the AR5 or AR6 basis deliberately, since here it moves the headline by about a tenth.
The four segments and their activity bases
The four manufacturing segments differ in which gases they use, what substrate the factor is keyed to, and — importantly — the unit the factor is published in. Integrated-circuit fabs and the heat-transfer-fluid line are in kilograms per square metre; flat-panel displays and photovoltaic cells are in grams per square metre. The engine normalises both, but the difference is worth understanding because it is the single easiest error to make by hand.
Semiconductor (IC fabs)
The full six-gas set — CF4, C2F6, CHF3, C3F8, NF3, SF6 — keyed to square metres of silicon, in kilograms per square metre. The largest and most gas-diverse segment, and the one the worked example uses.
TFT-FPD (flat-panel displays)
Three gases — CF4, NF3, SF6 — keyed to square metres of display glass, in grams per square metre. A thousand times smaller a unit than the semiconductor rows, which is the unit trap to watch.
PV cells (photovoltaics)
Two gases — CF4 and C2F6 — keyed to square metres of silicon, in grams per square metre. Carries an IPCC default that only half of PV manufacture uses fluorinated compounds, applied and disclosed by the engine.
Heat-transfer fluids
A single line — a C6F14-equivalent proxy for the perfluorinated fluids used to cool process tools — keyed to square metres of silicon, in kilograms per square metre. Small but completeness-relevant.
| Segment | Gases | Substrate | Factor unit |
|---|---|---|---|
| Semiconductor | CF4, C2F6, CHF3, C3F8, NF3, SF6 | m² silicon | kg / m² |
| TFT-FPD | CF4, NF3, SF6 | m² display glass | g / m² |
| PV cells | CF4, C2F6 | m² silicon | g / m² (× CPV 0.5) |
| Heat-transfer fluids | C6F14-equivalent | m² silicon | kg / m² |
The factor unit splits by segment. Semiconductor and heat-transfer-fluid factors are in kilograms per square metre; flat-panel and photovoltaic factors are in grams per square metre — a thousandfold difference. The engine normalises grams to kilograms automatically, but a hand calculation that treats a flat-panel gram-per-square-metre factor as kilograms overstates that segment a thousandfold. Always check the unit on the row before working with a factor outside the tool.
The photovoltaic segment carries one further parameter: the IPCC default that only half of photovoltaic manufacturing uses fluorinated compounds, a fraction of 0.5 applied to the PV factors. The calculator applies it and states it on the result, because it is a disclosure point — a reviewer needs to know the PV figure already carries that assumption rather than counting every cell as fluorinated.
The etch gases and their emission factors
Every factor below is an IPCC 2006 default from Volume 3, Chapter 6, Table 6.2, read live from MasterBrain at calculation time. They are grouped by segment, with the unit shown on each row — the unit being the thing that varies and the thing to read first.
| Segment | Gas | Factor | Unit |
|---|---|---|---|
| Semiconductor | CF4 | 0.9 | kg / m² silicon |
| C2F6 | 1.0 | kg / m² silicon | |
| CHF3 | 0.04 | kg / m² silicon | |
| C3F8 | 0.05 | kg / m² silicon | |
| NF3 | 0.04 | kg / m² silicon | |
| SF6 | 0.2 | kg / m² silicon | |
| TFT-FPD | CF4 | 0.5 | g / m² glass |
| NF3 | 0.9 | g / m² glass | |
| SF6 | 4.0 | g / m² glass | |
| PV cells | CF4 | 5.0 | g / m² silicon |
| C2F6 | 0.2 | g / m² silicon | |
| Heat-transfer fluids | C6F14-equiv. | 0.3 | kg / m² silicon |
The global-warming potentials — and a gas-to-key trap
Each gas converts to CO2e through its global-warming potential. The table below gives both the AR5 and AR6 100-year values, alongside the MasterBrain key the engine uses to look each one up — which is where a subtle trap lives. The perfluorocarbons use a PFC_ key, but CHF3 is fluoroform, which is also known as HFC-23, and its potential is stored under the HFC key, not a CF key. Looking it up by the wrong key returns nothing and silently drops the gas from the total.
| Gas | GWP key | AR5 (100-yr) | AR6 (100-yr) |
|---|---|---|---|
| CF4 (PFC-14) | PFC_CF4 | 6,630 | 7,380 |
| C2F6 (PFC-116) | PFC_C2F6 | 11,100 | 12,400 |
| C3F8 (PFC-218) | PFC_C3F8 | 8,900 | 9,290 |
| CHF3 (fluoroform / HFC-23) | HFC_23 | 12,400 | 14,600 |
| NF3 | NF3 | 16,100 | 17,400 |
| SF6 | SF6 | 23,500 | 25,200 |
| C6F14 (PFC-5-1-14) | PFC_C6F14 | 7,910 | 8,620 |
CHF3 is fluoroform, also designated HFC-23, and its global-warming potential is stored under the HFC-23 key — not a perfluorocarbon key. An inventory that looks for a CHF3 or CF-style key finds nothing and silently drops the gas, understating the total. The perfluorocarbons use PFC_ keys; CHF3 alone uses HFC_23. The engine maps this correctly; the caution is for anyone reconciling the numbers by hand.
For the full per-gas warming-potential record — formulae, lifetimes, and the AR5-to-AR6 change for each gas — see the IPCC AR6 GWP values reference. The general concept is covered in the global-warming potential glossary entry.
Tier 1 versus Tier 2 — gross defaults versus abatement
The calculator offers two methods per line, and the difference is whether abatement is credited. Tier 1 reports the gross gas escaping before any destruction. Tier 2 is the gas-by-gas mass balance that credits both the gas consumed in the process and the gas destroyed in installed abatement — using your fab’s own figures, because IPCC publishes no facility-level defaults for them.
| Method | What it computes | Inputs |
|---|---|---|
| Tier 1 (gross, by area) | Substrate area × default factor × GWP, per gas, summed. No abatement credit. | Segment + substrate area |
| Tier 2 (mass balance) | E = FC × (1 − U) × (1 − a·d): gas consumed (FC) less the fraction used in process (U) and the net fraction abated (a·d). | Gas + consumed mass + utilisation U + net abatement a·d |
The Tier 2 mass balance
Tier 2 is where a fab with abatement gets credit for it. The mass balance starts from the gas consumed, removes the fraction used or transformed in the process — the utilisation, U — and then removes the net fraction destroyed by abatement, which is the fraction of gas routed to an abatement device multiplied by that device’s destruction-or-removal efficiency. A fab running plasma abatement that destroys most of its perfluorocarbons can report a fraction of its Tier 1 gross figure. An optional module also handles CF4 formed as a by-product of other gases, using a fab-supplied formation factor.
The Tier 2 utilisation and abatement figures are your fab’s, not defaults. IPCC publishes no facility-level utilisation or destruction-efficiency defaults for electronics — those depend on the specific tools and abatement installed — so the calculator takes them as inputs rather than supplying a number. Enter a destruction efficiency only if it is measured or certified for your abatement equipment; claiming abatement you cannot evidence understates the inventory.
How the calculation works
Each line follows the path for its tier. A Tier 1 line takes a segment and a substrate area; a Tier 2 line takes a gas, a consumed mass, and the abatement figures. The engine reads the factors live, applies the gas-by-gas warming potentials, and sums every gas into one total with a per-gas split.
What you enter, what the engine derives
For a Tier 1 line you select the segment and enter the substrate area — and you pick the segment, not the gas, because the engine applies the whole gas set for that segment automatically. It normalises the area unit to square metres and the factor mass unit to kilograms, applies the photovoltaic fraction where relevant, weights each gas by the selected warming-potential basis, and sums. For a Tier 2 line you supply the gas, the consumed mass, and the utilisation and abatement fractions, and the engine runs the mass balance. You never handle the kilogram-versus-gram difference yourself.
The per-gas operation
At Tier 1 the operation per gas is substrate area times the per-square-metre factor, normalised to kilograms, times the warming potential, divided to tonnes of CO2e — with the photovoltaic fraction of 0.5 applied on PV lines. At Tier 2 it is the consumed mass times one minus utilisation times one minus net abatement, then times the warming potential. Either way the gases are summed and reported individually, so the dominant gas is visible. There is no CO2 in this calculator at all — every line is a high-warming fluorinated gas, which is why the warming-potential basis is the most consequential setting on the page.
Before reading the result, confirm three things: the segment matches the substrate, the warming-potential basis matches the rest of your inventory, and — if you are at Tier 2 — the abatement figures are measured rather than assumed. The unit on the factor is handled for you, but the basis and the abatement inputs change the headline materially, so they are worth a second look.
Worked example — an IC fab wafer-area inventory
A worked Tier 1 inventory shows the method and the gas-mix dominance together. The fab below processes 50,000 square metres of silicon a year across the full six-gas semiconductor set. The factor values are live MasterBrain figures; the area is an illustrative input. The basis is AR5, the default.
The process ledger
| Gas | Factor (kg/m²) | Emitted mass | × GWP (AR5) | CO2e |
|---|---|---|---|---|
| C2F6 | 1.0 | 50,000 kg | 11,100 | 555,000 t |
| CF4 | 0.9 | 45,000 kg | 6,630 | 298,350 t |
| SF6 | 0.2 | 10,000 kg | 23,500 | 235,000 t |
| NF3 | 0.04 | 2,000 kg | 16,100 | 32,200 t |
| CHF3 | 0.04 | 2,000 kg | 12,400 | 24,800 t |
| C3F8 | 0.05 | 2,500 kg | 8,900 | 22,250 t |
| Total | — | 111,500 kg | — | 1,167,600 t CO2e |
Each figure reconciles as area × factor × GWP ÷ 1,000; only the substrate area is illustrative. Gases are listed by CO2e contribution, not emitted mass — the reordering is the point. Factor values via MasterBrain v2026.203, IPCC 2006 Vol 3 Ch 6, AR5 basis. The per-gas split is charted in the GWP-leverage section above.
The gas listed sixth by emitted mass — SF6 at ten tonnes — is the third-largest by CO2e, because its warming potential dwarfs the others. C2F6 leads on both a large emitted mass and a high potential. On the AR6 basis the total rises about 10.6% to roughly 1.29 Mt CO2e, with C2F6 still on top — the reweighting changes the magnitude, not the ranking.
Why the ranking reorders
By emitted mass the order is C2F6, CF4, SF6, then the three trace gases. By CO2e the order is the same at the top but the gaps change completely: SF6 closes most of the distance to CF4 despite emitting less than a quarter of CF4‘s mass, because its warming potential is more than three times CF4‘s. This reordering is exactly why the per-gas split matters — an abatement programme that targeted the largest emitted mass would start in the wrong place.
Reading the result — which gas to abate first
The most useful thing this calculator tells a fab is not the total — it is the ranking. Abatement is gas-specific: a destruction unit is plumbed to particular tools and particular gases, and installing it has a cost. The gas to abate first is the one with the largest CO2e contribution, which the per-gas split identifies directly. In the worked fab that is C2F6, then CF4, then SF6 — three gases that together carry 93% of the footprint, so abating them captures almost the whole opportunity.
Abate by CO2e contribution, not emitted mass. The two rankings differ because the warming potentials differ so widely — a gas emitted in small quantity can dominate the footprint, and a gas emitted in large quantity can be modest in CO2e. The per-gas split is the abatement roadmap: target the top contributors, and a Tier 2 mass balance then shows the credit once the abatement is installed.
Read intensity alongside the total — CO2e per square metre of substrate is the number that compares fabs and tracks progress as abatement comes online. Because the gases are so potent, a small improvement in destruction efficiency on the dominant gas moves the intensity more than a large change in any trace gas, which is why the ranking, not the gas count, drives the decarbonisation plan.
Tier accuracy and when each applies
The two tiers answer different questions. Tier 1 is a standardised gross estimate from substrate area; Tier 2 is the fab’s own abatement-adjusted figure. A regulated inventory generally needs Tier 2, because gross default factors overstate a fab that operates abatement — sometimes by a wide margin.
| Tier | Method | When it applies |
|---|---|---|
| Tier 1 (this tool, gross) | Substrate area × IPCC default factor × GWP | Screening estimates, first inventories, fabs without measured abatement data, cross-checks |
| Tier 2 (this tool, mass balance) | Gas-by-gas FC × (1 − U) × (1 − a·d) with fab-supplied utilisation and abatement | Fabs with measured consumption and certified abatement; most regulated reporting |
| Tier 3 | Tool-level or continuous measurement of actual emissions | Highest-accuracy verified inventories where direct measurement is in place |
The honest framing is that a Tier 1 gross figure will overstate any fab that abates, often substantially, because modern abatement destroys most of the perfluorocarbons it treats. A fab with abatement should move to the Tier 2 mass balance to claim that reduction; a fab without it, or without measured destruction efficiencies, stays at Tier 1 and reports the gross figure honestly. Tier 3 tool-level measurement is the highest tier and sits beyond this calculator.
Tier 1 is gross and screening-grade; it credits no abatement. A fab running destruction equipment will report far less at Tier 2, but only with measured utilisation and destruction figures to support it. For a regulated inventory the Tier 2 mass balance is usually expected — this tool carries it, but the abatement inputs must be your fab’s evidenced values, not assumptions.
Process versus energy emissions — the boundary
Electronics manufacturing has a large energy footprint — fabs are power-intensive — but that energy is not what this calculator measures. The boundary here is between the fluorinated process gases and everything else, and keeping them apart is what makes both numbers correct.
What belongs here, and what belongs elsewhere
The fluorinated etch and chamber-clean gases belong in this calculator as Scope 1 process emissions. The electricity that powers the fab — typically its largest single climate impact — is a Scope 2 emission computed from consumption and a grid factor, not here. Fuel burned on site for heat or backup power is a Scope 1 combustion emission under a separate inventory. The three are distinct, and a fab’s full footprint needs all of them; this tool isolates the process gases so the gas-mix story is clean.
| Belongs in this calculator (process F-gas) | Belongs elsewhere (energy) |
|---|---|
| Unreacted CF4, C2F6, CHF3, C3F8, NF3, SF6 from etch and chamber-clean | Grid electricity powering the fab (Scope 2, usually the largest line) |
| The C6F14-equivalent heat-transfer-fluid loss | On-site fuel combustion for heat or backup power (Scope 1, separate inventory) |
| CF4 formed as a process by-product (Tier 2 module) | Purchased steam, chilled water, and abatement-unit fuel |
The audit failures to pre-empt
01 — Gram factor read as kilogram
A flat-panel or photovoltaic factor in grams per square metre treated as kilograms. This overstates that segment a thousandfold. The engine normalises it; a hand calculation will not.
02 — CHF3 dropped on a wrong key
CHF3 looked up under a perfluorocarbon key instead of HFC-23. The lookup fails and the gas silently vanishes from the total. Fluoroform’s potential lives under the HFC-23 key.
03 — Abatement claimed without evidence
A Tier 2 destruction efficiency entered without measured or certified support. This understates the inventory by whatever fraction was assumed. Abatement credit needs evidence.
04 — AR5 and AR6 mixed
Some gases weighted on AR5 and others on AR6. Because the gases are so potent, an inconsistent basis shifts the total materially. Set one basis for the whole inventory.
05 — PV fraction double-applied or omitted
The photovoltaic 0.5 fraction applied twice, or removed without cause. The engine applies it once and discloses it; do not re-apply it downstream or strip it without a documented reason.
06 — Process gas omitted as immaterial
Treating the fab as purely an energy problem and skipping the F-gases because their mass is small. Their CO2e is not small — it is often the largest part of the fab’s direct footprint.
Reporting context — F-gas Regulation, EU ETS, IPCC, SBTi
Semiconductor process gases feed several reporting and regulatory regimes, and the tier and basis that satisfy each one differ. A Tier 1 screening figure is a starting point for all of them and a sufficient figure for none of the regulated ones.
| Framework | Role for semiconductor F-gas emissions | Tier expected |
|---|---|---|
| IPCC 2006 Guidelines, Vol 3 (IPPU) | The source of the method and the default factors. Chapter 6 defines the electronics-industry process boundary this calculator computes. | Tier 1–3 framework |
| EU F-gas Regulation 2024 | Governs fluorinated greenhouse gases, including the reporting and phase-down framework most directly relevant to these process gases. | Reporting / phase-down |
| GHG Protocol Corporate Standard | Places these process emissions in Scope 1. The consolidated corporate total rolls process, energy, and indirect emissions together. | Method-agnostic |
| EU ETS | Where a fab falls under the scheme, requires monitored, verified emissions — the Tier 2 mass balance or measurement, not a gross default. | Tier 2–3 / measured |
| SBTi Corporate Net-Zero | Target-setting against a base-year inventory. F-gas abatement is a major near-term lever for electronics manufacturers and feeds the Scope 1 base year. | Inventory-grade |
Use the AR5 or AR6 basis the receiving framework specifies, and keep it consistent. Because these gases are so potent, the basis choice moves the total by around a tenth — more than enough to matter in a regulated filing. The GHG Protocol and most current disclosure regimes use AR5, which is this calculator’s default; some inventories are moving to AR6. Mixing the two within one inventory produces a figure that reconciles against neither.
For the corporate roll-up that consolidates this process figure with energy and indirect emissions into one organisational total, the process line carries into the GHG inventory aggregator as a Scope 1 entry. A dedicated fluorinated-gas inventory aggregator that brings these gases together with HFCs and other F-gas sources is on the roadmap and will be linked here when it publishes.
Data sources, model, and factor basis
The model — source and structure
The calculator reads its factors from the semiconductor-gases keyspace in MasterBrain — under the semiconductors.tier1.*, tft_fpd.tier1.*, pv_cells.tier1.*, and heat_transfer_fluids.tier1.* sub-industry prefixes — sourced from IPCC 2006 Guidelines Volume 3, Chapter 6 (Electronics Industry Emissions), Table 6.2. Every row is a Scope 1 process factor, and resolves live by key at calculation time, so a figure computed today and the same figure recomputed after a data-layer release are distinguishable by the MasterBrain version stamped on the output.
No fallback floor for factors — em-dash on miss
The process factors carry no hardcoded fallback value. If a factor cannot be read from MasterBrain, the calculator renders an em-dash and skips that line with a banner rather than a stale or invented number — the house rule across GreenCalculus value lookups. The warming-potential constants are the one exception: they are mirrored in the engine as an offline fallback so that a gas can still be weighted if its live GWP row is briefly unavailable, which is how the heat-transfer-fluid line computed correctly even before its C6F14 potential was added to the data layer. The emission factors themselves are always live reads with no floor beneath them.
A missing factor shows an em-dash, never a guess. The emission factors have no fallback floor by design. The only hardcoded values are the gas warming potentials, mirrored from the data layer as an offline safeguard — and even those exist only to convert the gas masses to CO2e, never to invent an emission factor.
GWP basis and completeness
Every line in this calculator is a high-warming fluorinated gas; there is no CO2 at all. That makes the AR5-versus-AR6 basis the most consequential setting on the page, and the calculator surfaces it as an explicit toggle defaulting to AR5. The seven gases — the six modelled plus the C6F14 heat-transfer proxy — each carry their own AR5 and AR6 potentials, with CHF3 weighted as HFC-23 per its chemical identity. The factor and GWP tables above are the canonical values, rendered live. For the warming-potential reference, see the IPCC AR6 GWP values data page.
A dedicated semiconductor etch-gases methodology page sets out the IPCC tier structure, the Tier 2 mass-balance equations, and the by-product handling in full; it is a roadmap page and will be linked here when it publishes.
Related process calculators
This calculator sits in the industrial-process fleet alongside the other Scope 1 emitter tools. The process figure it produces is a Scope 1 line that consolidates into a full corporate inventory, and it sits beside the other fluorinated-gas and process tools.
The closest neighbour is the Scope 1 aluminium smelting PFC calculator, which computes the same family of perfluorocarbon emissions from a different industry and shares the AR5/AR6 basis treatment. For other industrial processes, the iron & steel process calculator covers ironmaking CO2, the chemicals process calculator covers nitric, adipic, and the petrochemical families, and the glass & ceramics process calculator covers carbonate-decomposition CO2. For the organisational roll-up, the GHG inventory aggregator consolidates Scope 1, 2, and 3 into one boundary total. The F-gas inventory aggregator brings HFCs, PFCs, SF6, and NF3 together into a single fluorinated-gas Scope 1 total, and the coal mine methane calculator covers fugitive mine CH4 on the same AR5/AR6 basis.
Quick converters: turn a single process-gas mass into CO₂e — C₃F₈, C₄F₁₀, c-C₄F₈, C₅F₁₂ and C₆F₁₄.
Frequently asked questions
It measures the Tier 1 Scope 1 process emissions of electronics manufacturing — the fluorinated etch and chamber-clean gases (CF4, C2F6, CHF3, C3F8, NF3, SF6) that escape unreacted, under IPCC 2006 Guidelines Volume 3, Chapter 6. You enter substrate area for a segment, and the engine multiplies by the default factor for each gas and weights it by global-warming potential. It does not measure the fab’s electricity, which is a separate Scope 2 emission.
Because the gases differ enormously in warming potential. SF6 traps 23,500 times the heat of CO2 on the AR5 basis, NF3 16,100 times, the perfluorocarbons several thousand times. So the CO2e contribution tracks which gas is used, not how much — a gas emitted in small mass can dominate, as SF6 does at a fifth of a worked fab’s total from a tenth of its emitted tonnage. Reading the per-gas split is what identifies the gas to abate first.
The IPCC factors are published that way: semiconductor and heat-transfer-fluid factors in kilograms per square metre, flat-panel-display and photovoltaic factors in grams per square metre. The engine normalises grams to kilograms automatically, so you never handle the difference inside the tool. The caution is for hand calculations — treating a gram-per-square-metre flat-panel factor as kilograms overstates that segment a thousandfold.
Yes, at Tier 2. Tier 1 reports the gross gas escaping with no abatement credit. Tier 2 is a gas-by-gas mass balance — emissions equal gas consumed times one minus the process utilisation times one minus the net abatement — so a fab running destruction equipment reports far less. The utilisation and destruction figures are your fab’s own inputs, because IPCC publishes no facility-level defaults for them; enter them only where they are measured or certified.
Use the basis your reporting framework specifies, and keep it consistent across the inventory. The calculator defaults to AR5, which matches the GHG Protocol and most current disclosure regimes; AR6 is a toggle. The choice matters more here than on most process tools because these gases were revised significantly between assessments — NF3 rises about 8%, C2F6 about 12%, CHF3 about 18% — moving a typical fab total by around a tenth.
Because they are the same molecule. CHF3 is fluoroform, designated HFC-23, with a global-warming potential of 12,400 on AR5 and 14,600 on AR6. Its potential is stored under the HFC-23 key rather than a perfluorocarbon key, so a lookup that searches for a CHF3 or CF-style key fails and silently drops the gas. The engine maps it correctly; the point matters only when reconciling figures by hand.
It is an IPCC default reflecting that only about half of photovoltaic-cell manufacturing uses fluorinated compounds. The calculator applies the 0.5 fraction to the photovoltaic factors and states it on the result, because it is a disclosure point — a reviewer needs to know the PV figure already carries that assumption rather than counting every cell as fluorinated. A fab with a known different fraction should use a site-specific value.
Four: integrated-circuit fabs (the full six-gas set, per square metre of silicon), flat-panel displays (CF4, NF3, SF6 per square metre of glass), photovoltaic cells (CF4 and C2F6 per square metre of silicon, with the 0.5 fraction), and the heat-transfer fluids used to cool process tools (a C6F14-equivalent proxy). You select the segment and the engine applies that segment’s gas set automatically.
Where a fab falls under the EU ETS, monitored and verified emissions are required — the Tier 2 mass balance with measured abatement, or direct measurement, not the Tier 1 gross default. Tier 1 overstates any fab that abates, so it is a screening estimate and a cross-check rather than the reported figure for a regulated installation. Use Tier 2 with evidenced utilisation and destruction efficiencies for regulated reporting.
The calculator shows an em-dash and skips that line with a banner rather than a fabricated value. The emission factors carry no hardcoded fallback floor by design. The warming-potential constants are mirrored in the engine as an offline safeguard so a gas can still be weighted if its live GWP row is briefly unavailable, but the emission factors themselves are always live reads. An em-dash is a signal to check the data layer, not a number to report.
Methodology notes and limitations
Scope and purpose. This calculator computes the Tier 1 Scope 1 process emissions of electronics manufacturing — the fluorinated etch and chamber-clean gases (CF4, C2F6, CHF3, C3F8, NF3, SF6, plus a C6F14-equivalent heat-transfer proxy) across four segments — under IPCC 2006 Guidelines Volume 3, Chapter 6. It does not compute the fab’s energy emissions: grid electricity is Scope 2 and on-site fuel is a separate Scope 1 combustion line.
Method — area times default factor, by gas. A Tier 1 line is substrate area multiplied by the IPCC default factor for each gas in the segment, normalised to kilograms, multiplied by the gas global-warming potential, and summed. The photovoltaic segment applies an IPCC default fraction of 0.5 for the share of manufacture using fluorinated compounds, and the calculator discloses it. Every line is a fluorinated gas; there is no CO2 in the calculation.
Tier 2 abatement. Tier 2 is a gas-by-gas mass balance — emissions equal gas consumed times one minus utilisation times one minus net abatement, with an optional CF4 by-product module. The utilisation and abatement figures are fab-supplied, because IPCC publishes no facility-level defaults for them; they should be entered only where measured or certified. Tier 1 credits no abatement and therefore overstates any fab that abates.
Units and the gas-to-key mapping. Semiconductor and heat-transfer-fluid factors are in kilograms per square metre; flat-panel and photovoltaic factors are in grams per square metre, normalised by the engine. The warming potentials are keyed by gas, with the perfluorocarbons under PFC keys and CHF3 under the HFC-23 key per its chemical identity — a mapping the engine handles but that can silently drop a gas if done incorrectly by hand.
GWP basis. The calculator defaults to AR5 100-year potentials and offers AR6 as a toggle. Because the gases are so potent, the basis materially affects the total — around a tenth for a typical fab. Set one basis for the whole inventory and do not mix the two; AR5 matches the GHG Protocol and most current disclosure regimes.
Factor basis and live reads. Factors resolve live from the semiconductor-gases MasterBrain keyspace (source IPCC 2006 Vol 3 Ch 6, Table 6.2) at calculation time, and the MasterBrain version is stamped on the output for restatement work. The emission factors carry no hardcoded fallback floor: a failed read renders an em-dash and skips the line. The gas warming potentials are mirrored as an offline fallback only.
No regulatory substitution. Results are estimates and do not constitute a verified inventory or an assurance opinion. For EU ETS installations the Tier 2 mass balance or direct measurement is generally required, and the basis must match the receiving framework. Review by a qualified practitioner is required before use in any regulated filing.
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