Cases

Case studies, from production lines.

Three AW-ZP04B lines: IGBT modules, lead frames and LED packaging. Customer names are withheld; the figures come from acceptance tests and production tracking on the customer’s line.

Case 01IGBT power modules · AW-ZP04B

Plasma before wire bonding, on IGBT module lines.

An IGBT module packaging line cleans substrates and frames with plasma after die attach and before wire bonding. The first AW-ZP04B passed validation and was replicated to further module lines — ten systems in total.

Customer
Power semiconductor packaging — IGBT modules. Name withheld.
Region
East China, on the customer’s line
Since
2023, continuous supply
Scale
10 × AW-ZP04B across several module lines
In the line
After die attach, before wire bonding
Process gas
Ar / H2 mixture
Contact angle after cleaning13.4°mean of 6 points · TO-247Pass · All points ≤ 20°
Cleaning uniformityCPK 1.5230 subgroups of 5Pass · Target CPK > 1.33
Wire bond pull force+31.7%8.2 → 10.8 gf · 30 points per batchPass · Target ≥ +30%
Weak-bond rate−85.0%1.20% → 0.18% · 100% line inspectionPass · Target ≥ −85%

The brief

Remove organic residue, oxides and fine particles from substrate and frame surfaces before wire bonding — to make bonds stronger and more consistent, and to cut weak bonds.

Requirements: no damage to the silver or copper plating; a measured contact angle after cleaning; a cycle time that keeps up with the line; recipe management and fault alarms.

What made it hard

  1. Complex module structure with steps and shadowed areas — hard for the plasma to reach evenly.
  2. Silver plating is sensitive to oxygen: discoloration after cleaning had to be prevented by controlling moisture in the chamber and when the door opens.
  3. A tight line takt — cleaning time balanced against output.
  4. The customer wanted the result verifiable twice: contact angle and pull test.

What we delivered

System
AW-ZP04B in-line RF
Chamber
Aluminum, 550 × 320 × 50 mm
Plasma
13.56 MHz RF, 0–600 W
Gas / pressure
0–200 mL/min · 30–100 Pa
On this line
~36 s per cycle, 4 strips · ~400 strips/h
Strips
L 150–280 × W 40–85 mm, auto width for 3–5 types

Lanes and carriers made to the IGBT module carrier size; Ar/H2 process; 20 stored recipes behind tiered passwords, so parameters cannot be changed by mistake.

  1. Site survey
  2. Solution sign-off
  3. FAT at Awing
  4. Installation
  5. Process validation
  6. Training
  7. Production follow-up
Magazines and strip transfer inside the AW-ZP04B in-line plasma cleaner
Magazine loading and strip transfer on the AW-ZP04B.
TO-247 lead-frame strip held in a gloved hand
TO-247 strip.
Copper lead-frame strips
Lead-frame strips.

Case 01Acceptance and production data

Accepted, then tracked for six weeks.

AW-ZP04B on the IGBT module line above. Customer name and product codes withheld; figures from the acceptance test and the six weeks after production start.

Acceptance criteria and results

ItemCriterionMeasuredResult
Contact angle after cleaning (TO-247)≤ 20°13.4° mean of 6 points, 11.198°–15.040°Pass
Cleaning uniformityCPK > 1.33CPK 1.52 (30 subgroups)Pass
Wire bond pull force≥ 30% above the level beforeMean 8.2 → 10.8 gf (n = 30 per batch), +31.7%Pass
Weak-bond rate≥ 85% below the level before1.20% → 0.18%, −85.0%Pass
Plating integrityNo plating damage from cleaningPush test + visual inspection: 0 casesPass
Running stabilityStable continuous running, no unplanned stops720 h continuous, 0 fault stopsPass

Before and after

Wire bond pull force

gf · mean of 30 points per batch

Weak-bond rate

% · 100% line inspection

Six weeks after production start

Weak-bond rate by week

% · 100% line inspection · six weeks after production start

Weekly results

WeekPull force, gfWeak-bond, %Angle, °Note
W110.40.2814.0First week
W210.60.2213.6Parameters frozen
W310.70.1913.2—
W410.80.1713.0—
W510.90.1612.8Lowest
W610.80.1813.2Re-check

Running and plating

CheckResultVerified by
Continuous running720 h without interruptionEquipment log
Fault stops0Line inspection records
Plating damage / oxidation discoloration0 cases (1,200 pcs sampled)AOI + push test
Chamber contamination and particlesNo abnormal deposits; particle count within limitWeekly chamber check
Process parameter consistencyPower / flow / pressure within ±3%Automatic recipe log
Customer acceptanceSystem and process acceptedSigned acceptance form

Contact angle, six points on TO-247

Water droplet on a TO-247 surface after plasma cleaning, measuring point 1, contact angle 15.040 degrees
Point 115.040°
Water droplet on a TO-247 surface after plasma cleaning, measuring point 2, contact angle 14.955 degrees
Point 214.955°
Water droplet on a TO-247 surface after plasma cleaning, measuring point 3, contact angle 11.482 degrees
Point 311.482°
Water droplet on a TO-247 surface after plasma cleaning, measuring point 4, contact angle 11.198 degrees
Point 411.198°
Water droplet on a TO-247 surface after plasma cleaning, measuring point 5, contact angle 14.987 degrees
Point 514.987°
Water droplet on a TO-247 surface after plasma cleaning, measuring point 6, contact angle 12.715 degrees
Point 612.715°

Mean 13.4°Range 3.84°Criterion ≤ 20° — all six points pass

How the data was taken. Tracking period: six weeks after production start (W1–W6). Pull force: 30 points per batch on a wire bond pull tester, mean value. Weak-bond rate: 100% inspection on the line, weak bonds ÷ total input. Contact angle: six points on TO-247 product, deionized water, AW-1 contact angle meter. CPK: 30 subgroups of 5, on the key uniformity dimension.

Before / after values are this line’s baseline before introduction and its measured level after. Droplet images are the meter’s original captures, cropped; the red arc is the fitted droplet profile.

Case 02Lead frames · AW-ZP04B

In-line cleaning of lead frames, docked to an automated line.

A semiconductor packaging company in East China cleans lead frames in line, between magazine loading and unloading, without adding waiting time to the line.

≤ 20°contact angle after cleaning
~400strips per hour, 4 per cycle
~36 sper cleaning cycle
≤ 65 dB(A)running noise
Customer
Discrete device and memory packaging. Name withheld.
Region
East and Southwest China, customer plants
Period
2024–2026
Scale
Several in-line systems, linked to automated packaging lines
System
AW-ZP04B with automatic width change

The brief

Remove stamping oil, oxide and fine particles from the frames, to improve adhesion in die attach, wire bonding and molding — without the damage that batch cleaning caused. Fully automatic: magazine in, clean, magazine out.

Requirements: dock to the existing rails, match the line takt, verifiable uniformity, safety interlocks and alarms.

What made it hard

  1. Thin frames deform easily — transfer and clamping need dedicated carriers.
  2. Heavy stamping-oil residue — power and gas ratio had to be matched to it.
  3. Little space on the line — a compact layout that meets the up- and downstream rail height.
  4. No stopping the line: installation and commissioning inside a planned shutdown window.

What we delivered

AW-ZP04B in-line RF plasma cleaner with jam prevention and detection, and automatic width change for 3–5 strip types. Four-lane chamber with bottom exchange transfer: cleaning, loading and unloading run at the same time to shorten the cycle. A pusher takes strips from the magazine automatically.

  1. Requirements
  2. Line survey
  3. Integration test at Awing
  4. Installation in shutdown window
  5. Commissioning
  6. Process validation
  7. Training
  8. Ramp-up support

Results

  1. Contact angle ≤ 20° on the cleaned frames; plasma uniformity checked with indicator test paper.
  2. Stable running at about 400 strips per hour (4 strips per cycle, ~36 s).
  3. Noise ≤ 65 dB(A) while running.
  4. Cleaning cycle matched to the line, with no added waiting.

Case 03LED packaging · AW-ZP04B

Before die attach and wire bonding, on LED lines running around the clock.

An LED packaging company in East China cleans lead frames and substrates in line before die attach and before wire bonding, across several packaging lines.

≤ 20°contact angle after cleaning
CPK > 1.33cleaning uniformity
24 hcontinuous operation
20stored recipes, one per product
Customer
LED and optoelectronic device packaging. Name withheld.
Region
East China
Period
2022–2025
Scale
In-line systems across several packaging lines
System
AW-ZP04B in-line RF

The brief

Raise the surface activity of lead frames and substrates, to improve adhesion in dispensing, die attach and wire bonding — and reduce weak bonds and delamination. Cleaning before die attach and before wire bonding.

Requirements: high throughput, low damage, consistency that can be measured.

What made it hard

  1. Small parts in large batches — uniformity matters on every strip.
  2. Lines run 24 hours: the system has to be stable and quick to maintain.
  3. Frequent product changes — recipes must switch fast, without mixing lots.

What we delivered

AW-ZP04B in-line RF plasma cleaner: 13.56 MHz, 0–600 W; process gas 0–200 mL/min; about 36 s per cycle, 4 strips per cycle, about 400 strips per hour. 20 stored recipes, each bound to a product type, so lots are not mixed.

  1. Sample trial
  2. Parameters locked
  3. Factory acceptance
  4. Installation
  5. Training
  6. Production follow-up

Results

  1. Contact angle ≤ 20° after cleaning; uniformity CPK > 1.33.
  2. 24-hour continuous running, with fault alarms and interlocks.
  3. In-line cleaning cycle meets the line’s UPH.

Related

The process behind these lines.

How plasma fits in the packaging line, and how the result is measured — or discuss your own process with an engineer.

Semiconductor packagingLED / IGBT packagingTest methods

Have a similar part?

Describe the part and the problem. A process engineer replies with a recommended format.

Start an inquiry awingtech@wxawing.com+86 510 8359 5266