Scope 3 Emissions Calculation Guide for the Semiconductor Industry
Korean title (as on the document): 반도체 업종을 위한 Scope 3 배출량 산정 안내서
A government guide that tells semiconductor suppliers where to start when a client asks for Scope 3 data.
ESG · Original 2025.03 · 3 min read
Summary
- Clients such as Samsung and SK hynix have to count the carbon emissions of the products their suppliers deliver as their own Scope 3 (purchased goods and services), which is why they ask suppliers for emissions data.
- Published in March 2025 by the Ministry of Environment and the Korea Environmental Industry & Technology Institute, this guide is tailored to the semiconductor industry and covers calculation methods for the 15 GHG Protocol categories, a value chain map, and how to judge materiality (priority).
- If a data request from a client has arrived, use it in this order: confirm which categories your company falls under, then calculate the most material items first.
Clients such as Samsung Electronics and SK hynix have sharply increased requests asking suppliers to "submit carbon emissions data for the products you deliver." Faced with a Scope 3 request that lands out of nowhere, a supplier staffer with no dedicated headcount and no background in the subject is left with no idea where to begin. This guide is the semiconductor-specific manual the government produced to take some of that helplessness away.
What is this document?
It is an official guide published in March 2025 by the Ministry of Environment and the Korea Environmental Industry & Technology Institute, which formed a joint working body with major semiconductor manufacturers and the Korea Semiconductor Industry Association. Building on the GHG Protocol, the internationally accepted standard for greenhouse gas accounting, it sets out how to calculate the indirect emissions (Scope 3) that arise in the semiconductor value chain, organised into 15 topics.
The key point is that it is "specific to the semiconductor industry." A general Scope 3 guide covers principles without distinguishing between industries, but this document points out which emissions arise where, along the actual flow of the semiconductor value chain. It is the starting point for getting a feel for what a supplier should answer, and in what form, when a client asks for data.
What is Scope 3, and why does it land on suppliers?
Greenhouse gas emissions are divided into three groups according to where the responsibility sits.
| Group | What it means |
|---|---|
| Scope 1 | Emissions from fuel burned directly at our own plant and from our own processes |
| Scope 2 | Indirect emissions from the electricity, steam and so on that we buy and use |
| Scope 3 | Everything else across the value chain — 15 categories covering raw material purchasing, transport, product use, disposal and more |
The point where suppliers get caught is the crux. From the client's side, the parts, materials and equipment a supplier delivers fall under "purchased goods and services" (Scope 3 category 1). In other words, a client cannot total up its own Scope 3 without emissions data for the products its suppliers make — and that is why the request lands on your desk.
In one sentence
A client's Scope 3 category 1 (purchased goods and services) = the carbon emissions of the products our company delivers. That is why the data request comes down to suppliers.
What to take away from this guide
If reading the whole document end to end feels like too much, checking just the four items below is enough to get the big picture for practical work.
4 things to look at in the guide
- Semiconductor value chain map — marks the emission points across 8 stages, from raw materials and equipment through chip fabrication, assembly and the final product
- Picking out, from the calculation methods for the 15 categories, the ones that apply to our company
- Table of example goods and services by value chain stage — wafers, process gases, metals, equipment and parts, set out item by item
- Materiality (priority) judgement — deciding what to tackle first by emission size and stakeholder interest
The value chain map and the "example goods and services by value chain stage" table in particular contain the very items we handle every day. Wafers (silicon, SiGe, GaAs), process gases (SiF6, CF4, SF6, ammonia), lithography and etching equipment, and parts such as photomasks and probe cards are all set out as emission sources, so you can see with your own eyes "where our company sits."
Materiality judgement also matters in practice. It is easy to wear yourself out trying to calculate all 15 categories perfectly, and the guide advises ranking priorities starting from the items with large emissions and high stakeholder interest. For a supplier that has to respond with limited headcount, this "select and focus" is the most useful part.
How to use it in practice
If a Scope 3 data request has come from a client, try using this document in the following order.
1. Confirm which category the request is asking about. In most cases it is the client's category 1 (purchased goods and services) — that is, the emissions of the products we deliver. Comparing it against the guide's value chain map shows where we sit.
2. Narrow down the emission sources that apply to our company. Not all 15: use the guide's list of raw material and equipment emissions together with its materiality criteria to work down from the largest items first.
3. Organise the data to match the guide's calculation methodology. Following the per-category method for which activity data is multiplied by which emission factor gives you the basis to answer in the format the client requires.
Doing it early pays off
If you work out in advance which categories and which material items apply to your company, before the request arrives, your response speed once the actual request lands is a different matter entirely.
Related resource: K-ESG Guidelines for Supply Chain Due Diligence
- [Source: Scope 3 Emissions Calculation Guide for the Semiconductor Industry (Ministry of Environment / Korea Environmental Industry & Technology Institute), 2025.03]
Note: The Scope 1/2/3 split and the 15-category classification follow the GHG Protocol, the international standard. For the details of semiconductor-specific calculation, check the original guide.
Published by Korea Environmental Industry & Technology Institute (KEITI). The source document is in Korean. Verify the source and current edition with the issuing body.
OpenEnergy service