OldRFguy
Junior Member level 1
Hi everyone,
In microstrip the field is predominantly between the track and the the groundplane beneath meaning that most of the conductive loss in the track will be on the underside of the foil where there is no plating and where the surface roughness depends on the way the substrate manufacturer manufactured the foil.
On GCPWG however there will,presumably, be a more significant contribution to loss from the field between the edges of the conductor and the 'walls' of the coplanar guide that are formed by the via holes bordering the track. Here, I would expect the losses to be significantly higher due to the losses through the Gold over Nickel plating which will, I suppose, change with frequency due to skin depth and the thickness of the differeent metal layers.
Is my analysis of this roughly correct and can anyone point me at some resources that describe these effects in a useful way?
Many thanks
OldRFguy
In microstrip the field is predominantly between the track and the the groundplane beneath meaning that most of the conductive loss in the track will be on the underside of the foil where there is no plating and where the surface roughness depends on the way the substrate manufacturer manufactured the foil.
On GCPWG however there will,presumably, be a more significant contribution to loss from the field between the edges of the conductor and the 'walls' of the coplanar guide that are formed by the via holes bordering the track. Here, I would expect the losses to be significantly higher due to the losses through the Gold over Nickel plating which will, I suppose, change with frequency due to skin depth and the thickness of the differeent metal layers.
Is my analysis of this roughly correct and can anyone point me at some resources that describe these effects in a useful way?
Many thanks
OldRFguy