a) Using the depletion approximation and C = dQs/dV, derive Eq (7.12) in the Semiconductor Device Fundamentals textbook: 2 NB(x) = qK EgA²d(1/C})/dv Note that under the depletion approximation Qs = QANBW (assuming a one-side junction), where W is the depletion region width on the lightly doped side. Also recall that the reverse- biased capacitance C = C, : W

In this Zener diode regulator, the source voltage varies from 8 V to 10 V. Assume that the load current varies between 2 mA and 45 mA, and that the diode is an ideal 4 V Zener diode. What is the largest allowable resistance that will ensure the load voltage remains constant with variations in load current and source voltage? Please enter your answer to 3 significant figures.

a) What is n-type semiconductor materials? What are the majority and the minority cariers? b) What is p-type semiconductor materials? What are the majority and the minority cariers? c) What is depletion region of a p-n junction diode? d) Describe in your own words the forward-bias and reverse- bias conditions of a p-n junction diode. e) Draw a Diode Symbol and label the anode and the cathode. Si Ge 2 ka f) Find V, in the circuit shown in +20 V 2 k2 15V Fig. Fuad Al-Mannai EENG261 Page 1

Capacitance per unit area at no reverse bias is two pF/cm². For a step graded diode of area 5cm², what is net capacitance at 99 V reverse bias voltage?

Capacitance per unit area at no reverse bias is two pF/cm2. For a step graded diode of area 5cm2, what is net capacitance at 99 V reverse bias voltage?