**2.2 Measure machines**

In addition, high-performance manufacturing machines are needed; so essential are also the measuring machines to improve the results. When the design frequency is increased, the dimensions of the prototype are reduced and manufacturing tolerances become more important, being necessary to characterize and avoid them as much as possible. To do that, some of the measuring machines explained next could be used.

### *2.2.1 Microscope*

It is very important to check the correct metallization of holes and walls, the correct milling of the prototype to avoid shortcuts, etc. To do that, a microscope can be used to check if there are manufacturing errors such as parts of copper that have not been properly removed or vias that are not properly metallized. Once identified, some of these errors can be handly solved to assure the correct behavior of the prototype.

#### *2.2.2 Vision measurement system*

This kind of machines are high-efficient systems that allow very high accurate measurements. These machines measure not only distances, but also geometrical 2D shapes, such as holes or lines and their deviations in shape and size from the initial requirements, allowing to compensate systematic errors during the manufacturing process.

### *2.2.3 Profilometer/surface roughness measuring systems*

These instruments measure the rugosity of the layers of the prototypes. They are very useful in order to estimate the effect of metallization.

## *2.2.4 Vector network analyzer*

These N-port devices are capable of measuring S-parameters, magnitude, phase, and time-domain analysis of prototypes. Combined with an anechoic chamber, it can measure antennas and radiation of prototypes.
