$2.$Find the dc reverse bias voltage for a silicon p$+-$i$-$n$+-$i$-$n$+$ IMPATT diode operated at $1$ A$.$

The thickness of the first i$-$region is $1\mathrm{.}5$ pm$,$ the second i$-$region is $4\mathrm{.}5$ pm$,$ and the doping

in the n$+$ion is $1$OIs cm$3$ with a width of $14$ nm$.$ The device area is $5$~$10$~ cm$2.$

Neglect the temperature effect.

$3.$ For the IMPATT diode in Prob. $2$:

$($a$)$ when the device is under avalanche breakdown condition, is the field in the drift region

high enough to maintain velocity saturation of electrons, and

$($b$)$ estimate the maximum cw power output of this device, assuming the diode capacitance

is $0\mathrm{.}05$ pF and Pf

$=$

constant