
28-Layer HDI in IT180A with 28:1 Aspect Ratio
High aspect ratio & super-thick multilayer HDI is a core strength at SPCB. We solve complex stacking, plating and impedance challenges for industrial control & communication high-end equipment.
High-layer HDI, heavy copper, fine-line impedance — and the DFM calls that kept them shippable.
4 representative builds

High aspect ratio & super-thick multilayer HDI is a core strength at SPCB. We solve complex stacking, plating and impedance challenges for industrial control & communication high-end equipment.

Want more routing space on your HDI board? Two DFM details matter most:

At the sharp edge of HDI: 2.8/2.8 mil lines under dense BGA, where impedance discontinuity and reflection most often appear. We validate:

This build integrates several demanding processes:
Widely applied in smart manufacturing, medical, automotive and AI hardware.
3 lessons from real enquiries

5 sets of files, 10 pcs each — but the Gerber called for PI + thermal copper paste via filling, while the spec sheet said FR4 TG170 + resin plug vias. On a 4 oz heavy-copper high-current board, the via-filling method directly impacts thermal performance.
We flagged the conflict before quoting; the client finalised the process based on our input, and we re-quoted with FR4 options.

A customer's breakaway tabs were only 0.9 mm wide and separating too early during routing. Our engineering review proposed two changes:
The customer's reply: "Please follow production Gerber." A small DFM adjustment at the file stage avoided a downstream yield issue.

A drawing specified 35 µm hole copper on an HDI board. We paused the order and confirmed, because this note is normally written by mistake:
3 detailed case studies

0.4 mm pitch BGA, laser microvias, ENIG finish, IPC Class III reliability.
SPCB's DFM review caught a critical hidden BGA microvia defect before build. Boards ship consistent, with complete documentation and reliable communication.

A previous fabricator's inconsistent resin plugging caused thermal hotspots and failed safety audits under continuous high-current load.
DFM review of copper balance, current paths and anti-arc creepage/clearance; tuned stack-up, 100% flying-probe test, thermal-impedance sampling, resin-void inspection.
All boards passed IEC anti-arc verification; void rate well below limit. A qualified solution with repeat orders for over 10 years.

A startup racing field validation needed fast-turn prototypes with precise differential impedance and durable gold fingers; prior vendors missed tolerance or lead time.
Rapid prototyping line (24h expedited), impedance coupons on every panel, plated gold fingers, full flying-probe test, cross-section samples and full test reports.
Impedance within ±5%; gold fingers passed insertion-cycle tests; samples shipped on schedule — design locked before mass production.
Send us your Gerber — our engineering team reviews it before production.
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