Review multilayer construction from the finished board inward: layer count, copper distribution, dielectric thickness, holes and controlled features. The specification register separates published limits from the conditions needed to build your particular board.
Read each value together with its board type and review conditions.
Published limits apply to their stated board type. Layer count, copper weight and minimum geometry require a combined engineering review.
These are individual rigid-board values. The final stackup and manufacturing drawing define the accepted combination.
On smaller screens, scroll within the table to see every column.
| Parameter | Published capability | Applies to | Review conditions |
|---|---|---|---|
| Maximum layers | 68L | Rigid PCB | Rigid-board limit; material, thickness and via structure require review |
| Finished inner / outer copper | 85oz / 85oz | Rigid layers only | Review the copper on each layer; minimum geometry cannot be assumed at maximum copper |
| Inner trace / space | 2.5/2.5mil | Inner copper pattern | Copper thickness, local density and etch allowance |
| Outer trace / space | 3/3mil | Outer copper pattern | Finished copper, plating and solder-mask definition |
| Board thickness | 0.4–11.5mm | Finished rigid board | Stackup, tolerance and hole depth considered together |
| Minimum mechanical drill | 0.1mm | Mechanical drilling | Distinguish drill-tool size from specified finished hole |
| Minimum laser drill | 0.075mm | Laser-drilled structure | Dielectric depth, pad, layer span and fill requirements |
| Mechanical / laser aspect ratio | 20:1 / 1:1 | Respective hole processes | Not interchangeable; confirm diameter and processed depth |
A process-panel format includes manufacturing margins. It is not the finished-board outline.
On smaller screens, scroll within the table to see every column.
| Parameter | Published capability | Applies to | Review conditions |
|---|---|---|---|
| Process panel formats | 600 × 770mm; 500 × 1200mm | Rigid process panel | Usable area, tooling margins, material format and structure |
| Minimum finished board | 10 × 10mm | Individual rigid outline | Panelization and handling must be defined |
| Maximum finished board | 22.5 × 30inch | Individual rigid outline | Confirm material format, tooling and required tolerances |
| Contour tolerance | ±0.1mm | Routed finished contour | Critical datums and local features belong on the drawing |
| Thickness tolerance below 1.0mm | ±0.08mm | Rigid boards <1.0mm | State finished nominal thickness and measurement requirements |
Artwork must describe the intended copper geometry and its relationship to holes and board edges.
Send one controlled revision of the fabrication layers and drill files. Identify polarity, copper text, fiducials, alignment targets and any registration-sensitive areas in the fabrication drawing.
For fine geometry, review the actual layer and copper thickness. Inner and outer limits are different, and a local high-density area may need a different process allowance from the rest of the board.
Use the finished copper requirement to review etching and plating with the circuit pattern.
Mask opening and dam values apply to the mask process; they are not replacements for copper spacing rules.
On smaller screens, scroll within the table to see every column.
| Parameter | Published capability | Applies to | Review conditions |
|---|---|---|---|
| Mask colors listed | Green, black, blue, red, white, purple, pink, yellow, matt black/green/blue, orange, clear or transparent | Rigid solder mask | Confirm color, material and compatibility with the board and assembly |
| Minimum clearance | 1.5mil | Rigid solder-mask clearance | Opening convention, registration and pad geometry |
| Minimum dam | 3mil | Rigid solder mask | Fine-pitch pad spacing, finish and assembly process |
Prioritize readable part identification without placing ink on exposed solderable surfaces.
On smaller screens, scroll within the table to see every column.
| Parameter | Published capability | Applies to | Review conditions |
|---|---|---|---|
| Legend colors | White, black, red, yellow | Rigid legend | Choose contrast against the selected mask |
| Minimum width / height | 4mil / 23mil | Legend features | Font, local space and readable orientation |
| Marking control | Drawing-defined | Revision and identification | State the exact content and permitted relocation areas |
These examples describe individual structures in our project reference material. They do not establish a general maximum or guarantee the same combination for a new design.
The reference records 28L HTG, 3.65mm board thickness, 15:1 aspect ratio, 3/4mil geometry and impedance control. Those values belong to that construction.
Individual engineering example; the combination is reviewed for each project.
A separate reference records a 24L backplane with press-fit holes and impedance control. Connector hole requirements must be specified for each new backplane.
Individual engineering example; the combination is reviewed for each project.
Let the drawing identify the non-negotiable features.
Include the drawing revision and acceptance requirements. The engineering review confirms the manufacturable combination before quotation.
No. It is the confirmed rigid-board maximum. Flex and rigid-flex have their own published limits and construction review.
Do not assume that combination. State finished copper per layer and the actual geometry for an etch, plating and stackup review.
No. The table lists them separately because manufacturing margins, material format and panel construction affect the usable area.
State whether the dimension is a drill-tool or finished-hole requirement, identify plated or non-plated status, tolerance and the layers it passes through.