Advanced thick film microcircuits are used when a simple one-side printed conductor pattern is not enough. Ceramic substrates can support compact interconnect, double-sided metallization, printed through connections, edge wrap conductors, fine-line patterns, solderable or bondable metallization, and precision singulation features. These options should be reviewed at the drawing stage because they affect cost, yield, inspection, and assembly method.
Advanced structure options
- Double-sided thick film circuits: front and back printed layers for compact routing or ground connections.
- Metallized holes: localized through connections or grounding when the substrate and process route support it.
- Wrap-over edge printing: conductor paths that connect top and bottom surfaces through an edge feature.
- Angled face printing: printed conductor or pad features on non-flat faces for special mechanical integration.
- Dielectric solder dams and protective glazes: printed insulation or protection to control solder flow, wear, or environmental exposure.
- Fine-line thick film: screen printed or photo-defined approaches for denser conductor layouts.
Metallization and assembly review
Metallization should be selected according to the final assembly process. Gold systems may be used for wire bonding, epoxy attach, or AuSn soldering. Silver-based systems can be cost-effective where soldering and migration risk are properly reviewed. Platinum-doped or mixed metallization systems may be considered when leach resistance, solder compatibility, or bonding method requires it.
Solder and attach features
Some hybrid circuits require pre-deposited or printed solder areas, die attach zones, or controlled solder dams. These features should be drawn separately from the electrical conductor pattern so the manufacturer can review registration, reflow behavior, thickness, and cleanliness.
Laser profiling and precision singulation
Substrate outline, notches, pockets, vias, serial marking, and cut features may be produced by laser profiling, scribe-and-break, milling, or diamond sawing depending on edge quality and tolerance requirements. For high-quality ceramic edges, the singulation method can be as important as the printed circuit itself.
Data formats for RFQ
Useful drawing formats include Gerber, DXF, DWG, GDSII, PDF, STEP, and annotated sample photos. For complex microcircuits, include layer naming, side identification, substrate thickness, via and edge connection details, metallization requirement, solder/bond method, and final test criteria.
Questions to answer before production
- Is the circuit single-sided, double-sided, multilayer, or edge-connected?
- Are holes mechanical only, metallized, or used as electrical connections?
- Does the assembly require wire bonding, soldering, AuSn attach, epoxy attach, or spring contact?
- Are fine lines required, or is standard screen printing sufficient?
- Which singulation method is acceptable for edge quality and cost?
- What inspections are required: continuity, open/short, line width, adhesion, bondability, solderability, or thermal test?