 Consider a goldGaAs Schottky diode with a capacitance of 1 pF at 1 V. What is the doping density of the GaAs? Also calculate the depletion layer width at zero bias and the field at the surface of the semiconductor at 10 V bias voltage. The area of the diode is 10^{5} cm^{2}.
 Using the work functions listed in table 3.2.1, predict which metalsemiconductor junctions are expected to be ohmic contacts. Use the ideal interface model.
 Design a platinumsilicon diode with a capacitance of 1 pF and a maximum electric field less than 10^{4} V/cm at 10 V bias. Provide a possible doping density and area. Make sure the diode has an area between 10^{5} and 10^{7} cm^{2}. Is it possible to satisfy all requirements if the doping density equals 10^{17} cm^{3}?
 A platinumsilicon diode (area = 10^{4} cm^{2}, N_{d} = 10^{17} cm^{3}) is part of an LC tuning circuit containing a 100 nH inductance. The applied voltage must be less than 5 V. What is the tuning range of the circuit? The resonant frequency equals , where L is the inductance and C is the diode capacitance.
 Consider two Schottky diodes with builtin potential f_{i} = 0.6 V. The diodes are connected in series and reversed biased. The diodes are identical except that the area of one is four times larger than that of the other one. Calculate the voltage at the middle node, V_{out}, as a function of the applied voltage, V_{in}. Assume there is no dc current going through either diode so that the charge at the middle node is independent of the applied voltage.
 A metalsemiconductor junction consists of platinum and gallium arsenide with N_{d} = 10^{17} cm^{3}. The applied voltage equals 3 V. Calculate the electric field in the semiconductor at the metalsemiconductor interface. Use f_{i} = 0.8 V.
 An aluminumsilicon Schottky diode has a breakdown voltage of 5 V. The silicon is ptype with a doping N_{a} = 10^{18} cm^{3}. Calculate the breakdown field and the depletion layer width. (F_{M} = 4.0 V)
 A metalsemiconductor junction, biased at an unknown voltage, has a doping density of 10^{17} cm^{3} and a capacitance of 1 pF. The semiconductor is ptype germanium, the builtin potential of the junction is 0.5 V and the diode area is 10^{4} cm^{2}. Calculate the depletion layer width and the applied voltage.
 A metalsemiconductor junction, biased at an unknown voltage, has a maximum electric field of 10^{5} V/cm and a capacitance of 1 pF. The semiconductor is ntype gallium arsenide, the builtin potential of the junction is 0.7 V and the diode area is 10^{4} cm^{2}. Calculate the doping density and the applied voltage.
 Silicon carbide contains three cigarshaped conduction band minima. The constant energy surfaces of these are ellipsoids which are given by:
and Derive an expression for the effective mass used in the Richardson constant for a flow of carriers in the zdirection. Derive an expression for the Richardson velocity in the zdirection. (Advanced problem, requires understanding of section 3.4.4.2)
