Overview

A lead frame etching service builds semiconductor lead frames straight from your drawing, with no stamping dies and no burrs on the terminals. Photochemical machining laminates a resist onto the strip, exposes it through artwork carrying every lead, tie bar, dam and locating hole, then dissolves the unprotected metal in a matched etchant. Because the pattern lives on film, a new lead frame layout costs nothing in tooling and a design revision is just updated artwork. Stock runs from 0.08 mm to 0.5 mm in copper C11000/C19400, alloy 42 (FeNi42) and copper-nickel-silicon C7025.

Semiconductor packaging cares about three things on a lead frame: fine pitch, consistent leads and coplanarity. A lead frame etching service removes metal chemically, so lead edges stay burr-free and stress-free, lead width and gap hold uniform across the panel, and plating deposits evenly without nodules. The etched strip stays flat, which makes formed-lead coplanarity easy to hold within ±0.10 mm once the frame is cut and bent. Leads, tie bars and process features all come off one panel, and every shipment carries a dimensional report for incoming inspection.

Parameter Window

• Available Materials: copper C11000/C19400, alloy 42 (FeNi42), copper-nickel-silicon C7025
• Material Thickness Range: 0.08–0.5 mm
• Tolerance: lead width ±0.02 mm; outline ±0.05 mm; formed-lead coplanarity ±0.10 mm on request
• Minimum Feature: lead width 0.08 mm on 0.15 mm stock; gap down to 0.05 mm; pitch to 0.20 mm
• Surface Options: pre-plating cleaning, selective Ni/Pd/Au or Ag plating frames, forming and lead bending, tape-and-reel packing
• Compliance: ISO 9001 process control, RoHS/REACH material traceability

Manufacturing Process / Workflow (8 Steps)

1. DFM & Pitch Review — Check lead pitch, tie bars and dams against stock thickness, then fold plating and forming allowances into the flat pattern.
2. Material Selection — Pick copper C11000/C19400 for conductivity, alloy 42 for thermal match or C7025 for strength, and verify strip flatness.
3. Cleaning & Lamination — Degrease the strip and laminate dry film resist under controlled heat and pressure so no bubbles sit under fine leads.
4. UV Exposure — Expose through high-resolution artwork registered to the strip edge, holding pitch and lead position across the panel.
5. Development — Wash out unexposed resist to open the lead pattern and tie bars, then inspect fine leads for residual film or pinholes.
6. Etching — Spray matched chemistry from both sides; time, temperature and line speed hold lead width and gap within ±0.02 mm.
7. Plating Prep & Forming — Strip and clean for plating, apply selective plating frames where the drawing calls for them, then form and cut the leads.
8. Coplanarity Check & Packaging — Verify lead width, pitch and formed-lead coplanarity against the approved sample, then pack in trays or tape-and-reel.

Core Advantages

1. No tooling cost: A new lead frame layout is only new artwork, so prototypes and revisions skip die cost and shorten development time.
2. Fine-pitch capability: Lead widths down to 0.08 mm on 0.15 mm stock hold repeatably, which keeps fine-pitch package yields high.
3. Burr-free terminals: Chemical removal leaves no burr and no hardened rim, so plating builds no nodules and lead edges stay clean.
4. Flat, stress-free strip: Etching adds no residual stress, so the strip stays flat and formed-lead coplanarity is easy to control.
5. Wide alloy range: Copper for conductivity, alloy 42 for thermal matching, C7025 for strength — one process covers all three families.
6. Pattern freedom: A lead frame etching service carries tie bars, plating dams and marking holes in the same artwork at no extra process cost.

Typical Applications

• QFP and TQFP lead frames: Fine-pitch lead frames for quad flat packages with tight width and pitch control.
• Power semiconductor frames: Heavier copper frames for power devices and modules where current and heat both count.
• Sensor package frames: Etched frames combining leads and mounting features for MEMS and pressure sensors.
• LED lead frames: High-reflectivity frames for LED packaging that balance conductivity and light extraction.
• RF and microwave packages: Low-profile frames with tight lead pitch for radio-frequency devices.
• Automotive IC frames: Robust frames built for temperature cycling and vibration in automotive electronics.

Design Notes & Process Considerations

1. Lead width versus thickness: Keep lead width at or above stock thickness; finer leads distort during etching and damage easily in handling.
2. Etch compensation: Sidewalls taper roughly half the etch depth per side, so oversize leads in artwork to land the final width after plating.
3. Tie bars and dams: Hold leads with tie bars through plating and forming, and cut them only after bending so lead position never shifts.
4. Coplanarity control: Formed-lead coplanarity depends on strip flatness and forming tooling — lock both early when ±0.10 mm is required.
5. Selective plating registration: Plating frames must register to the lead pattern, so etch alignment marks with the leads in the same artwork.
6. Burr-free edges help plating: Because a lead frame etching service removes metal chemically, terminal edges stay smooth and insulation gaps between fine leads remain reliable.