Effects of manufacturing limitations upon coplanar waveguide designs at high microwave frequencies

To date, the effect of dimensional errors using standard printed circuit board etch processes on the transmission line (TL) response at mm-wave frequencies has not been investigated. While sidewall curvature due to etch has a negligible effect upon transmission line characteristics when the dimensions are in units of mm - these dimensional errors can become significant at higher GHz frequencies where dimensions are 10s of micrometers to achieve a 50 Ohm line impedance. These various geometric errors are studied in terms of the broadband microwave and mm-wave response on coplanar waveguide (CPW) transmission lines.