In this edition of Coonrod’s Corner, John Coonrod discusses RF influences due to hole wall roughness of plated through hole technology for applications in the frequency range for 5G and millimeter waves. It has been well known that the copper surface roughness, at the substrate-copper interface within a laminate, can impact the insertion loss and phase response of a circuit. Plated through hole (PTH) via’s usually have a hole wall roughness which is relatively smooth, but in some cases, the PTH via wall can be rough. Typically the PTH via wall roughness is dictated by PCB fabrication processing, but there is one particular material which naturally causes the PTH via to have a roughened hole wall surface. The RO4730G3™ laminate is a dominant material of choice in 5G applications and due to an unusual hollow sphere filler used within this laminate, circuits made with this material will generally have rougher PTH hole walls than other materials. This video gives a summary of several studies which were done to investigate the potential for the PTH via hole wall roughness to impact RF performance, for circuits operating in the frequency ranges of 5G applications.

Register to become a member of the Technology Support Hub to access presentations, videos and literature.

https://landing.rogerscorp.com/6/Tech-Hub-CC.aspx