## Common ground
All options are types of vapor deposition equipment used in advanced manufacturing, primarily for semiconductors, electronics, or display technologies.
## Options at a glance
**8479.89 – CVD & ALD systems**
- **Defining trait:** Uses chemical reactions between gases to deposit thin films; precise control at atomic scale.
- **Typical examples:** Silicon nitride deposition in microchips, ALD for high-k dielectrics.
- **Best fit when:** Depositing materials via gas-phase chemistry (e.g., SiH₄ + NH₃), especially for nanoscale or high-purity films.
**8486.20 – Semiconductor vapor deposition**
- **Defining trait:** Designed specifically for semiconductor device fabrication, often with high throughput and integration.
- **Typical examples:** CVD reactors in wafer processing lines, epitaxial growth systems.
- **Best fit when:** The system is used in semiconductor manufacturing (e.g., silicon wafers, transistor layers), regardless of deposition method.
**8486.30 – Flat panel display vapor deposition**
- **Defining trait:** Optimized for large-area, uniform coatings on glass or flexible substrates (e.g., OLEDs).
- **Typical examples:** Deposition of organic layers in OLED screens, transparent conductive oxides (TCOs).
- **Best fit when:** The apparatus coats large surfaces (e.g., 6th-gen display panels) for visual devices.
**8543.70 – PVD systems (e.g. HiPIMS)**
- **Defining trait:** Uses physical processes (sputtering) to eject material from a target onto a substrate.
- **Typical examples:** Aluminum or titanium coating in memory chips, reflective layers in displays.
- **Best fit when:** The system relies on ion bombardment of a solid target (not gas reactions), especially for metallic films.
## Key differences
| Feature | 8479.89 (CVD/ALD) | 8486.20 (Semiconductors) | 8486.30 (Displays) | 8543.70 (PVD) |
|-----------------------|-------------------|----------------------------|--------------------|---------------|
| Deposition method | Chemical reaction | General semiconductor use | Large-area coating | Physical sputtering |
| Substrate size | Small (wafers) | Small to medium | Large (panels) | Medium |
| Material type | Dielectrics, films| Semiconductors | Organics, TCOs | Metals |
## How to choose
- Does it use gas-phase chemical reactions (e.g., precursors reacting in chamber)? → 8479.89
- Is it used for semiconductor wafer processing (e.g., transistors, ICs)? → 8486.20
- Is it designed for large flat panels (e.g., OLED TVs, touchscreens)? → 8486.30
- Does it use sputtering from a solid target (e.g., magnetron, HiPIMS)? → 8543.70
## Overlaps & pitfalls
- A system used in semiconductor manufacturing may also deposit films on large substrates; prioritize **main application**.
- CVD systems can be used in both semiconductors and displays—use **8486.20** if for chips, **8486.30** if for panels.
- PVD (8543.70) may be used in semiconductor or display contexts—but only if the core method is sputtering.
- If unclear, define by **primary function and substrate type**