Containment action: hold all lots from chamber A. Re-cal the M2 etch recipe and re-qualify with 5 monitor wafers.
Containment action: 100% profile metrology on WIP. Re-cal the bias power LUT and re-qualify with 10 monitor wafers.
recipe change log
Recipe recipe_id was tweaked: change, expected to effect.
配方 {ID} 被微調:{變更},預期 {效果}。Etch 部門配方變更紀錄的句型。
Recipe E2-M2-RIE was tweaked: bottom power +50W, expected to bring profile back to 89°.
Recipe E2-CONT-RIE was tweaked: over-etch +15%, expected to clear the polymer footing.
— 真實場景 · Real Scenarios · 共 3 條 —
Email — ER Drift After Chamber Clean
Etch 工程師發給 PIE 跟 PQA,chamber clean 後 ER 出問題。
Subject: [HEADS UP] ER drift on chamber A after 03/12 wet clean
Hi all,
Quick update before this afternoon's PIE meeting.
After the routine wet clean on chamber A on 03/12, ER on the M2 trench recipe drifted from 220 nm/min baseline to 195 nm/min. SPC tagged it at the 3rd post-clean monitor lot.
Investigation so far:
- Chamber B is clean — drift is chamber-A-only.
- Polymer buildup on chamber wall not the cause; checked via OES baseline.
- Suspect is gas flow controller drift on the CF₄ line. Equipment is on it.
Containment: 3 lots on chamber A held; rerouted to chamber B.
Will share root cause confirmation by tomorrow EOD.
Thanks,
Etch ENG
相關縮寫:ER · SPC · PIE · OES
Conf Call — Profile Excursion Disposition
Yield review 上 PIE 點名 Etch 解釋 profile 異常,Etch lead 發言 1 分鐘。
Thanks. Quick update on the profile excursion on M2 trench.
We saw a 2.1° outward profile lean on lots Q3-217 through Q3-220 — four consecutive lots, all on chamber A.
Root cause is identified: bottom electrode power drifted by 12% after the routine PM on 03/12. The thermal recovery curve looks fine, but the impedance match dropped.
Containment: chamber A held for two days; recipe bias power was bumped up 60W; we ran 5 monitor wafers — profile back to 89.5°.
Long-term: we're updating the chamber qualification spec to include the impedance match check after every PM.
Five lots affected; all held at WAT. PQA confirms no customer impact — these are running on internal qual.
Open to questions.
5.0 Process Capability — Microloading Assessment
5.1 Observation
On the M3 contact etch, CD on dense regions (pitch ≤ 90 nm) ran 8% smaller than CD on isolated regions (pitch ≥ 200 nm). Effect was consistent across 12 evaluation lots.
5.2 Pareto Analysis
- 60% of the variation is attributed to ARDE (aspect-ratio-dependent etching) on the dense pads.
- 25% is attributed to plasma density variation across the wafer (microloading).
- 15% is residual chamber-to-chamber matching error.
5.3 Mitigation
- Recipe tuned: source power +8%, bias power +30W. Reduces microloading from 8% to 3%.
- Dense-iso CD compensation in the OPC model: +1.2 nm bias on dense features.
- Both changes qualified with 10 monitor wafers; SPC stable for 4 weeks.
5.4 Cpk Result
M3 contact CD: Cpk = 1.42 across dense + iso (was 1.05 before mitigation). Capable.