the carrier distribution in the conduction band is:nc(E) = gc(E) . f(E)   a) For a non-degenerate semiconductor, show that nc(E) has a maximum at E = Ec + ½ kT b) What is the ratio of carrier distribution at E = Ec + kT to that of the max value ?

A ALAS semiconductor crystal has a lattice constant of a = 0.13 nm, the volume density of As atoms in this crystal will be: O 3.641e24 /cm^3 2.048e30 /cm^3 O 1.821e24 /cm^3 O 3.550e16 /cm^3 O 1.593e24 /cm^3

A solid with electrons localized on lattice sites is often modeled by so- called "tight-binding" model. In this 1D model the dispersion relation is E(k)= -2Eo cos(ka), where a is the lattice constant. Starting from the effective equation of motion, describe how the electron moves in such a model under the influence of the constant electric field. Assume you measure electrical current as a function of time without any scat- tering. You will find an oscillatory behavior for the current. What is the frequency of this current? This is not observed in practice because scattering will exist.

A full-wave bridge rectifier is constructed using 4 germanium diodes, each with a forward voltage drop of 0.3 V. The rectified waveform is described by the function vout(0) = V, sin 0 - 2 Vp where 8 = sin1 (2Vp/V,). Use integration to determine the exact average value of Vout for V, = 1.5, 2, 2.5, 3, 3.5, 4, and 4.5 V (using Excel or Matlab will speed up this process considerably). Then use the estimation formula (0.636 V, - 2 Vp) to determine the average value for each value of V, above and find the percent difference between the exact and estimated values for each V, value. At what value of V, does the percent error become greater than or equal to 5%? OVs = 2 V OVs - 1.5 V OVs - 2.5 V OVs - 3V

The conductivity of a semiconductor is 250 S/m at 20 °C and 1100 S/m at 100 °C. Prove that the band gap of this semiconductor is 0.263 eV.

1.0 Biased PN Junctions Consider two PN diodes, A and B as depicted below. Suppose the junction area for each diode is 1.0 x10-8 cm² (1 square-micron) P-doped N-doped N = 1016 1/ cm3 Ng = 1017 1/cm³ X, *po Vo в P-doped Na = 1018 1/cm3 N-doped Ng = 1017 1/cm3 Х ро Xno V. a) At VD =0 Volts, which diode has the wider total depletion region width (value (in microns) and what is it? b) At Vp =0 Volts, in which diode the magnitude of the maximum electric field in the depletion region is the largest and what is its value (in V/cm)? c) Under a reverse bias Vp <0, which diode will breakdown first (i.e. at a smaller magnitude of the negative bias).

Q': Assuming the ideal diode model (VOn=0 V), calculate VoUT for the circuits in Figures (b) and (c) for the following input voltages (your answers should be in a table similar to that given below) 4k VOUT,b νουτε v20 v20 4k (b) (c) V1 V2 5

Example 1: Find the hole concentration in N-type semiconductor when the donor concentration is 2 x102cm-3 and intrinsic value of silicon material at T = 300° K is 1.25 x10 cm-3. ст %3D ст

The ratio of the effective density of states in the conduction band atEc+ 2kbT to the effective density of states in the valence band at Ev- KbT ?

What will be the majority and minority carrier concentrations in a P-Type Semiconductor, if the intrinsic concentration at 300 K is 1.45 x 1010/ cm3, and the dopant acceptor atom concentration is 1015/ cm3?