Techniques for the Integration of High - Q Millimeter - Wave Filters in Multi - Function Mmic Modules

technology. They can be made on-chip along with an amplifier, mixer, multiplier, or other active circuit, or they can be printed separately on a ceramic substrate like alumina. The latter approach is usually most economical since real estate on III-V semiconductor wafers is costly compared to that of passive substrates, and they can easily be packaged alongside other MMICs and connected with bond wires just like any other chip. The microstrip approach is suitable for most low pass filters and band-pass filters that require wider stop bands than can easily be accomplished with waveguide. The Q of microstrip filter resonators is often not very good, however, and high order filters with more than 4 or 5 poles are usually