Notebook: Wet Process · Bench 3 · Bath #7 (SC-1 sibling chemistry, 익명)
이 책의 규칙: ink only; “MES는 나중에 update” 금지
2026-07-12 — Install / fill
New bath target mix. TOC·particle baseline 기록. Operator: J.K.
Note: heater PID tuned; recirculation filter DP = 0.4 bar.
2026-07-18 — “Still fine”
Visual OK. Titration 없음. Production이 changeout “weekend까지” defer 요청.
Margin note (supervisor): weekend는 chemical property 아님.
2026-07-21 — First whisper
Metrology: 이 bench만 exit wafer에서 slight particle uptick. Split lot bench-correlated 확인.
Action taken: none. Action discussed: “monitor.”
2026-07-23 — Titration (finally)
Active species target 대비 low. Stabilizer odd. Filter DP 1.1 bar.
Bath age: soft SOP max 7 “or by titration” 대비 11 days.
Titration이 optional이면 lifetime은 folklore.
2026-07-23 — Changeout
Drain / rinse / refill. Filter replaced. Baseline two lot 내 복구.
Scrap은 이미 3일 “unknown fab particles”로 booked.
2026-07-25 — 이 책에서 rule rewrite (slide 아님)
Changeout trigger (하나만 firing):
- Calendar max hours (hard)
- Titration window 밖 (hard)
- Filter DP limit (hard)
- Bench-correlated particle signature (hard)
- Production preference (never)
Adjacent page에서 붙인 cross-check
| Signal | Bath #7 | Bath #6 (control) | | --- | --- | --- | | Particle delta | + | flat | | Titration | late | on schedule | | Filter DP | high | nominal | | Ownership | shared shrug | named wet owner |
Adjacent fences
UPW는 facility water purity. CDA는 dry air. Photoresist track은 coat/develop. AMC hunt는 airborne organics. 아무도 Bench 3 bath titration cadence 소유 아님. Titration refuse한 bath에 UPW blame 금지.
Notebook은 MES가 same gate enforce할 때까지 control system.
Last line (2026-07-28)
Bath #7 reminder: wet lifetime은 measured, negotiated 아님. Book에 time 없으면 happened 아님.