508 Microwave Engineering
13.3.2.4 Leakage Current
It is the ow of small current (of μA or pA order) in diode when it is reverse
biased. In PN junction diode ow of such current is due to the minority carri-
ers in the semiconductor. The level of leakage current depends on the reverse
voltage, temperature and the type of material.
13.3.2.5 Junction Capacitance
All PN junction diodes exhibit junction capacitance. This capacitance exists
between the two plates assumed to be formed at the edges of depletion
region. Width of depletion region is the dielectric spacing between these
plates. The value of this capacitance depends on the reverse voltage which
alters the width of depletion region. This property of formation of capaci- ...