
513Microwave Diodes
material is used for all the three areas. Silicon is the most commonly used
material in PIN diodes. It has better power-handling capability and provides
a highly resistive intrinsic region. For improving the speed of response GaAs
is an alternative. The intrinsic semiconductor increases the area of depletion
region which is useful for switching applications as well as for use in photodi-
odes, among others. The layer structure of PIN diode is shown in Figure 13.6.
The semiconductor sandwich of p-type, intrinsic and n-type materials gives
this diode its name. Thus, it may be written as P-type—Intrinsic—N-type. As
no practica ...