Design Rules
Design rules for thick-film circuits and hybrid modules
In order to develop a thick circuit or hybrid circuit, corresponding layout rules must be observed. Of course, depending on the paste material and the height of the conductor tracks, there are deviations from the general design rules.
The most important design rules relate to line / space distances, distances to the edge, the via diameter, etc.
Our standard layout rules are:
| - Vias for 0.38mm thick substrates: | Ø 0,2mm |
| - Minimum line / space distance: | 8 mils / 203 μm / 0,008" |
| - Minimum trace width: | 8 mils / 203 μm / 0,008" |
| - Minimal ring around the via: - Covered with dielectric: |
8 mils / 203 μm / 0,008" 4 mils / 101 μm / 0,004" |
| - Solder mask overhang: |
4 mils / 101 μm / 0,004" |
| - Distance to the edge: | 12 mils / 304 μm / 0,012" |
| - Minimum wirebond pad size: |
12 mils / 304 μm / 0,012" |
|
- Pad size 25 μm Au wire: |
8 mils x 8 mils |
| - Hole distance to the edge |
≥ Substrate thickness |
| - With the ring around the via: | 12 mils / 304μm / 0,012" |
| - Free space for the laser scribe lines: |
4 mils / 101 μm when scratched from the opposite side |
Depending on the layout, material, substrate thickness, metallization thickness, etc., special solutions can be offered. We would be happy to help you develop your thick-film substrate.
© 2012 Hubert Heusner 
