(a) What is the forward transit time τF for an npn transistor with a base width WB = 0.5 m and a base doping of 1018/cm3?
(b) Repeat the calculation for a pnp transistor. A transistor has a dc current gain of 200 and a current gain of 10 at 75 MHz. What are the unity-gain and beta-cutoff frequencies of the transistor?