p-i-n diodes for the modulation of mm-wave frequencies

A theoretical expression for a figure of merit Q
s
with respect to RF losses and switching time for p-i-n diodes is given. A fabrication technique is presented which is especially suited to obtain a large Q
s
. The static, dynamic, and RF data of the diodes and their performance in a 180-degree phase shift modulator at a frequency of 35 GHz and a bitrate of 256 Mbit/s are presented.