RF sources at millimeter wavelengths encounter significant problems in manufacturing for two reasons. First, the device dimensions vary inversely with operating frequency. Second, as the frequency increases, skin depths shrink and circuit losses increase. This means that the surface finish of the RF circuits must improve while the fabrication tolerances become more difficult to achieve. This has forced the adoption of alternate circuit fabrication methods that are significantly different from the lathe and mill machining used in lower frequency devices.
展开▼
