Overview

Etched metal foil in reel form is thin continuous metal — typically below 0.1 mm — that has fine features etched through or into it while it runs coil to coil. Because foil is too thin and too delicate for stamping, shearing or laser cutting without distortion, photochemical etching is often the only practical way to put dense holes, slots, flexures and traces into it. The foil is cleaned, laminated with dry film, exposed and developed, then etched under light, controlled tension so the finished product comes off the line flat, burr-free and wound to a customer spool.

The advantage of etched metal foil in reel lies in what it enables downstream. Fine through-holes and narrow webs that would tear under a press are formed chemically, and the whole length is produced in one pass with feature-to-feature pitch locked by the artwork. Typical materials are stainless steel 304/316L, copper C1100/C1020 and nickel Ni200, from 0.02 mm up to about 0.1 mm, with thinner gauges handled on request. The format suits applications where thousands of delicate parts must arrive pre-aligned on a strip — filtration mesh, sensor flexures, encoder gratings, battery tabs and micro connector contacts.

Parameter Window

• Available Materials: stainless steel 304/316L, copper C1100/C1020, nickel Ni200, Alloy 42, beryllium copper
• Material Thickness Range: 0.02–0.1 mm foil; 0.01 mm on request
• Tolerance: ±0.01 mm on feature size, ±0.02 mm on repeat pitch
• Minimum Feature: 0.05 mm hole and 0.05 mm web at 0.05 mm foil
• Surface Options: bright annealed, electroplated Ni/Au/Sn, passivated
• Compliance: ISO 9001 process control, RoHS/REACH material traceability

Manufacturing Process / Workflow (8 Steps)

1. Artwork Review — Convert to vector artwork, check hole diameters and web widths against foil thickness, and confirm spool and winding details.
2. Foil Qualification — Inspect the incoming foil for gauge, surface finish, pin-holes and edge condition, and record lot traceability.
3. Cleaning & Lamination — Degrease the foil and laminate dry film at low, even tension so thin material does not stretch or crease.
4. UV Exposure — Expose through registered films on a stationary or indexed web to hold front-to-back alignment on the thin gauge.
5. Development — Wash out unexposed resist to open holes and traces, then inspect for residual resist and broken fine webs.
6. Etching — Run the foil through matched chemistry at a gentle line speed; undercut and sidewall control are critical on thin stock.
7. Stripping & Rinse — Remove the resist, neutralize and rinse, then apply plating or passivation as required.
8. Recoil & Inspection — Rewind onto the customer spool and run in-line vision over hole size, web width and pitch before packing.

Core Advantages

1. Stamping-free precision: Foil too thin for dies is etched cleanly, preserving holes and webs that a press would tear or distort.
2. Locked pitch on the reel: Feature spacing is set by the artwork, so thousands of parts stay aligned on the strip without individual fixturing.
3. Flat, burr-free output: Chemical removal leaves no burr or edge curl, keeping thin foil flat for lamination or automated handling.
4. Fine holes and narrow webs: Holes and webs down to 0.05 mm hold across the full coil, beyond what mechanical cutting can sustain.
5. No tooling cost: Each revision is a new film set, so prototype and production runs start without stamping or progressive dies.
6. Wound to your spool: The finished foil arrives on your core diameter with the right winding direction and interleave, feed-ready.

Typical Applications

• Filtration and screening mesh: Fine uniform holes etched into stainless or nickel foil for filters and screens.
• Sensor flexures: Thin stainless foil with fine holes and narrow flexure arms for pressure and flow sensing.
• Encoder gratings: Dense slits and gratings on coiled foil for rotary and linear encoders.
• Micro connector contacts: Fine contact fingers etched into beryllium copper foil on reels for high-density connectors.
• Battery tabs and collectors: Nickel and copper foil etched with cell tabs and current collectors for lithium cells.
• Optical apertures: Precision through-apertures in thin foil for beam shaping and mask applications.

Design Notes & Process Considerations

1. Gauge versus feature: Keep hole diameter and web width at or above 1 × foil thickness, or undercut and tearing will dominate.
2. Tension limits: Foil stretches under tension; specify flatness and strip width so unwind and rewind tension can be kept low and even.
3. Registration for double-sided work: For two-sided features, include fiducials so front and back align within tolerance on the thin gauge.
4. Pinhole avoidance: State whether pin-holes are acceptable, as thin foil can carry pre-existing voids that affect final quality.
5. Surface and plating: Name the finish and any plating system up front, since thin foil oxidizes quickly and plating must follow stripping closely.
6. Spool and interleave: Specify core ID, winding direction and interleave material so the delicate foil is not damaged in transit or feed.