Schottky barrier diodes are the most established components
for mixing and frequency multiplication in the range 100 GHz - 2.5 THz.
Whisker contacted devices offer a mature technology and have been successfully used up to 2.5 THz,
but the whisker contact is sensitive to mechanical vibrations.
Planar devices for integration provide the possibility of integration and consequently robust circuits for THz applications.
The whole fabrication process of planar devices and especially of integrated structures
covers a variety of different technologies.
Some of these technologies are rather new or very specific.
The fabrication process of planar Schottky diodes is known to only few experts in this area.