Apparatus and method for broadband electromagnetic mode suppression in microwave and millimeterwave packages

A package for an electrical circuit, comprising:

• a first conductive surface;
• a second conductive surface;
• a resistive layer disposed at a first fixed distance from the first conductive surface and a second fixed distance from the second conductive surface;
• a first dielectric material, having a relative dielectric constant greater than unity, disposed between the resistive layer and the first conductive surface;
• and
• a second dielectric material, having a relative dielectric constant greater than or equal to unity, disposed between the resistive layer and the second conductive surface,
• wherein the first distance, the second distance and the relative dielectric constants of dielectric layers disposed between the resistive layer and the conductive surfaces are selected such that propagation of a TE mode is suppressed in amplitude over a selected frequency interval;
• and, the resistive layer has an intrinsic resistance of at least 30 Ohms per square.