Delivering 0-defect semiconductor part with 400 micro-holes
2026-09-08 · Engineering Note
Precision isn't an accident—it's a system
We recently completed a challenging prototype order: just 2 pieces of high-density insulator plates for a semiconductor automation line.
The workpiece is made of EP GC203 (T155) glass epoxy laminate—a material notorious for tool wear and edge chipping. To make it harder, the plate features nearly 400 precision holes (including almost 292 stepped holes with ∅1.68 H7 tolerance [+0.01/0]).
When producing low-volume, high-complexity parts, a single mistake means instant scrap. Here is our 5-Step QA Protocol for this project:
- A1 Print Inspection (Visual Clarity) Instead of standard A3/A4 prints, we enlarged the engineering drawing to A1 format. This allowed operators and inspectors to cross-check all 400+ dimensions without missing microscopic callouts.
- 3D Model vs. 2D Drawing Cross-Verification CAD models don't always match the official 2D PDF drawing. Our engineers checked every single feature in the STP file against the PDF before generating CAM code, avoiding costly scrap caused by missing drawing revisions.
- Dedicated Pin Gauge 100% In-Situ Inspection For 1.68H7 holes [+0.01/0], we customized dedicated Go/No-Go Pin Gauges (1.680mm Go / 1.695mm No-Go). Every single hole was verified directly on the machine bed before un-clamping.
- Material-Specific Tooling & Delamination Prevention (Post-Match Review)
To prevent fiber delamination on EP GC203, we optimized specialized carbide drills and cutting speeds, ensuring ultra-clean entry and exit edges across all 400 holes.
- Thermal Stability & Pitch Hole Position Control (Post-Match Review)
Drilling nearly 400 holes consecutively can generate localized heat, causing slight pitch drift. We optimized the toolpath sequence to balance heat distribution and guaranteed precise hole-to-hole position tolerances across the entire plate.
Reflecting after every complex job is how we grow.
Continuous improvement isn't just a slogan—it's built into every part we ship.
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