Why is photochemical etching used for lead frames?

Two big reasons. (1) Burr-free square edges — etched lead-frame tips are flat and parallel so the wire bond land is consistent shot-to-shot, which is critical for fine-pitch QFN. (2) Half-etch capability — chemistry can be stopped mid-thickness to create the downset pad that locks the chip in place during encapsulation, without a second stamping die or laser pass.

What alloys are used for lead frames?

C194 (Cu-Fe-P), C7025 (Cu-Ni-Si), Kovar (Fe-Ni-Co, glass-to-metal) and 194 FeNi42 are the workhorses. Each has its own etchant (Cu-Fe-P is etched in CuCl₂, Kovar in FeCl₃ then HNO₃ for the nickel-rich layer) and an adhesion-promoting pretreatment. GE configures the chemistry switch at build.

What tolerance can a reel-to-reel lead-frame line hold?

Standard is ±0.02 mm pad width with ±0.01 mm positional accuracy, on a 0.10–0.30 mm strip, at line speeds up to 4.0 m/min. For DFN-style fine-pitch (down to 0.20 mm pitch), our precision horizontal module adds an optical alignment loop and slows the line to 1.5 m/min for ±0.01 mm positional repeatability.

Can the line integrate pre-plating?

Yes. Half-etch pad → Ag spot plating for wire-bond is the most common. Our reel-to-reel lines are built so the etch module sits upstream of an inline spot-plating module; downstream processes (matte-tin, NiPdAu lead finish, encapsulation window punching) are integrated on request.

What is strip width and thickness range?

GE reel-to-reel etching machines accept strips 25–650 mm wide × up to 8000 mm long, at 0.05–0.50 mm thickness. Most lead-frame programmes use 60–200 mm strip × 70 m coils running 24/7.

Home/Etching Machines/Semiconductor Lead Frames

Lead frame etching machine

Reel-to-reel photochemical etching for QFN, DFN, SOP, QFP and lead-frame carriers. C194 / C7025 / Kovar, ±0.02 mm pad width, half-etch downsets, burr-free edges. Continuous inline spot-plating ready. Built for IC-package volumes.

Modern lead frames ask for two things that stamping can't quite deliver: flat, parallel lead tips for fine-pitch QFN wire bonding, and half-etch downset pads that locate the die accurately inside the encapsulant. Reel-to-reel photochemical etching hits both at 4 m/min on a 70 m coil — and the strips come out with the residual stress annealed out, which is why OSAT buyers prefer it for tight-pitch QFN.

By package

Lead-frame parts made on GE etching lines

📦 QFN / DFN lead frames

0.30–0.50 mm pitch, C194 alloy. Etch + Ag spot.

🔌 SOP / QFP lead frames

0.40–0.80 mm pitch, C7025 alloy. Matte-Sn lead finish inline.

📐 Lead-frame carriers & carriers

25–200 mm strip. Half-etch pockets for die location.

🧪 Kovar header lead frames

Glass-to-metal seal. FeCl₃ + HNO₃ chemistry switch.

🔋 Power-IC lead frames

Thick strip 0.30–0.50 mm. Half-etch downsets + Ag plating.

💡 LED lead frames

Cu alloy strip. Reflector-cup half-etch.

Recommended machine

Reel-to-reel etching line

Designed for the QFN/DFN/SOP volume band.

Continuous strip Reel-to-reel etching machine for lead-frame production

Reel-to-Reel Etching Machine

Strip width25–650 mm × L
Strip thickness0.05–0.50 mm
Line speed1.5–4.0 m/min
Pad-width tolerance±0.02 mm
Half-etchMid-thickness control ±0.005 mm
Throughput≈ 400–1500 m² / shift

Inline-ready for spot-plating, matte-tin and OSP modules.

View machine specs →

Fine pitch Precision horizontal etching machine for fine-pitch lead frames

Precision Horizontal Etching Machine

Etch area650 × 2000 mm batch
Pad tolerance±0.01 mm positional
Best forR&D / DFN pilot
EtchantCuCl₂ with auto regeneration

Pilot for new lead-frame designs and small batches.

View specs →

Alloys

Lead-frame alloy chemistry

Cu-Fe-P (C194)

CuCl₂ etchant, additive-controlled. Standard QFN.

Cu-Ni-Si (C7025)

CuCl₂ / HNO₃ blend. High-strength power-IC lead frames.

Kovar (Fe-Ni-Co)

FeCl₃ then HNO₃. Glass-to-metal-seal headers.

Cu-Fe / FeNi42

FeCl₃. Higher-temperature automotive & aerospace.

Silver-spot plating

Inline Ag-cyanide-free spot module for wire-bond land.

Matte-tin finish

Inline Sn matte plating for lead-finish compliance.

GE machine lineup

Lead-frame etching — pick the right machine

Reel-to-reel is the default. Pilot & R&D work goes on the horizontal precision line.

GE-RTR650-LF GE-RTR650-LF reel-to-reel lead-frame etching machine

GE-RTR650-LF — Reel-to-Reel Production

Continuous lead-frame etching with half-etch + inline plating options.

Strip width	25–650 mm
Strip thickness	0.05–0.50 mm
Line speed	1.5–4.0 m/min
Pad-width tolerance	±0.02 mm
Half-etch accuracy	±0.005 mm
Inline modules	Laminate, expose, develop, etch, strip, plate
Throughput	approx. 400–1,500 m² / shift

GE-JM650-H (LF pilot) GE-JM650-H lead-frame precision horizontal etching

GE-JM650-H — Pilot & R&D

For new lead-frame designs and DFN fine-pitch work.

Etching area	650 × 2000 mm batch
Tolerance	±0.01 mm positional (DFN)
Pad tolerance	±0.01 mm
Etchant	CuCl₂, auto regeneration
Best for	DFN / QFN pilot & small batches

Related etching lines & guides

Six things to read next — same chemistry, similar tolerances, or the next step in your process.

Planning a lead-frame line?

Send us your part drawing, alloy and annual volume. We'll spec the etch module, half-etch accuracy and the inline plating add-ons.

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