Copper & Brass FeCl₃

Chemical Etching Formula
C1100 T2 copper with FeCl₃

For engineers selecting an etching chemistry for C1100 T2 copper, the FeCl₃ formula shown here defines the bath composition, temperature window, and achievable feature sizes across a 0.02-0.08 mm thickness band. Typical mass-production yield for this recipe is 98.6%, with a typical conveyor speed of 4.51 m/min at 45°C.

Formula Summary

The table below summarizes every parameter that defines this etching formula. Values listed as ranges scale with sheet thickness across the supported band.

FeCl₃ Etchant System
36 °Bé Concentration
1.340 Specific Gravity
45 °C Bath Temperature
Through etch (double-sided) Etch Depth Type
0.02-0.08 mm Thickness Range
0.04 mm Typical Thickness
1.71-11.9 m/min Conveyor Speed Range
4.51 m/min Typical Speed
24-96 μm Min Hole Ø Range
100 μm Min Line Width Range
46126 μm Undercut Range
2.83 Etch Factor (EF)
98.6% Typical Yield (98.4-98.7%)

Why FeCl₃ for C1100 T2 copper?

Ferric-chloride-based formulas are the industrial workhorse for ferrous, nickel, and copper-bearing alloys like C1100 T2 copper. The Fe³⁺ ion oxidizes the metal surface; where HCl is present it regenerates dissolved species and stabilizes chloride concentration. The result on C1100 T2 copper is anisotropic etching with predictable undercut and an easily regenerated spent bath.

Process Window & Bath Control

Hold the bath at 45°C with concentration 36 °Bé (specific gravity 1.340). Across the 0.02-0.08 mm thickness range, conveyor speed runs from 1.71-11.9 m/min — thinner sheets move faster, thicker sheets slower, in roughly inverse proportion to thickness. A typical mid-range setpoint is 4.51 m/min for 0.04 mm stock. Use redundant PID temperature control to hold the bath within ±1.5°C, and titrate at least once per shift.

Design Rules & Tolerances

Design rules for this recipe: hole diameter 24-96 μm, line width 100 μm, single-side undercut 46126 μm — all as a function of thickness across 0.02-0.08 mm. The higher the etch factor (this formula holds about 2.83), the tighter the achievable tolerance. Below the minimum feature sizes, yield falls off steeply, so treat those numbers as hard floors rather than targets.

Design Rule Summary
• Minimum hole diameter range: 24-96 μm
• Minimum line width range: 100 μm
• Single-side undercut range: 46126 μm
• Typical etch factor (EF): 2.83

Yield & Production Economics

Expect a yield in the 98.4-98.7% range for C1100 T2 copper with FeCl₃, with 98.6% typical on a well-controlled line. Most rejects trace back to upstream coating and exposure rather than to the etch bath itself, so tightening photolithography control is usually the fastest path to a higher number.

Typical Applications

Parts produced with the FeCl₃ formula on C1100 T2 copper are common in lead frames, busbars, flexible heater elements, RF gaskets, and precision electrical contacts. The burr-free, stress-free nature of chemical etching makes it the preferred process wherever flatness and edge quality matter more than raw throughput.

More Copper & Brass Formulas

Other formulas in the same material family.

C1020 OF Copper FeCl₃ Through etch (double-sided) C1100 T2 copper FeCl₃ Through etch (double-sided) C1100 T2 copper FeCl₃ Through etch (double-sided) C1100 T2 copper FeCl₃ Through etch (double-sided) C1100 T2 copper FeCl₃ Half etch (single-sided) C1100 T2 copper FeCl₃ Half etch (single-sided)

Frequently Asked Questions

Standard pre-treatment is degrease, micro-etch to activate the surface, rinse, photoresist lamination or coating, UV exposure through the artwork, and develop. Pre-treatment quality directly drives yield for C1100 T2 copper: poor degreasing causes resist adhesion failures that show up as random pinhole defects in the etched pattern.

Need a Quote for This Process?

WET Etched runs production wet chemical etching lines using the FeCl₃ chemistry. Send us your part drawing and quantity for a full process quote.

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