Buffered Oxide Etch (BOE) – NH₄F/HF
Electronics‑grade • Restricted (HF)
Components
NH₄F (buffer) / HF (etchant)
Form
aqueous solution
Appearance
clear, colorless
Hazard
HF‑containing • corrosive • toxic
Use
semiconductor wet etch of SiO₂
Supplied as sealed, pre‑mixed solutions for cleanroom use. No
mixing instructions are provided. Always consult the SDS and your
site SOPs before handling.
| Commercial designation | Description | Notes |
|---|---|---|
| BOE 6:1 | Buffered oxide etch; stronger etch within BOE range | For faster SiO₂ removal; verify etch rate per process |
| BOE 7:1 | Balanced removal/uniformity | Common in general oxide patterning/clean |
| BOE 10:1 | Milder etch within BOE range | Higher selectivity vs certain masks; verify locally |
Exact composition and etch rates are supplier‑ and lot‑specific and depend on temperature, agitation, oxide quality, and loading. We provide COA per lot; qualify in your line.
| Parameter | Electronics‑grade (typical) | Spec |
|---|---|---|
| Total metals (each) | ≤ 5 ppb | ≤ 10 ppb |
| Particles (≥0.5 µm) | ≤ 200 / mL | ≤ 500 / mL |
| Chloride / Sulfate (each) | ≤ 100 ppb | ≤ 200 ppb |
| pH (buffered) | stable (lot‑specific) | within control band |
| Appearance | clear, colorless | — |
Specs vary by BOE ratio. Full analytical data supplied on COA.
| Material | Compatibility | Notes |
|---|---|---|
| SiO₂ | Yes (target) | Process‑dependent etch rates; qualify |
| Si₃N₄ | Often selective | Check selectivity vs oxide for your stack |
| Photoresist (typ.) | Mask‑dependent | Verify resist family & bake |
| Glass / Quartz | No | HF attacks silicates; avoid |
| Metals (Al, Cu, etc.) | Variable | Corrosion/attack possible; verify |
| Container | PTFE / HDPE | Use HF‑compatible plastics only; never glass |
| Item | Status | Notes |
|---|---|---|
| Restriction | Business‑to‑Business only | We do not supply to individuals or residential addresses |
| Transport | Hazardous (corrosive) | Class/UN depend on concentration; carrier approvals required |
| Handling | Trained personnel only | Use in wet bench/fume hood; HF‑compatible PPE and materials |
| Emergency | Follow SDS/SOPs | HF requires site‑specific protocols; keep calcium gluconate per SOP |
| Storage | HF‑compatible containers | Cool, ventilated; segregate from incompatibles |
This product contains hydrofluoric acid (HF). Severe toxicity and delayed injuries are possible. Always follow your facility’s HF program and SDS. No consumer sales.
Information provided is for product selection only and is not a
substitute for your process qualification or safety documentation.
SDS and COA are available to approved customers.