Question 1 (30 points) Gallium arsenide (GaAs) has a zincblende structure. Its lattice constant is 5.65 Å (1 Å = 1×10–8 cm). (a) How many arsenic atoms the unit cell below contains? Please show your calculation. How many gallium atoms does the unit cell contain? (8 points) (b) On its (100), what is the atomic density of arsenic atoms? That is, how many arsenic atoms are there on a 1-cm2 area? Show your procedure to obtain this number. The unit should be atoms/cm2. (7 points) (c) Determine the atomic density of gallium arsenide in atoms/cm3, that is, the total number of gallium and arsenic atoms in a 1-cm3 volume. (7 points) (d) If the atomic mass unit (AMU) of gallium and arsenic atoms are 69.7 and 74.9, respectively (1 AMU = 1.6605 × 10–24 grams), what is the density of gallium arsenide in grams/cm3. (8 points)

Question 3: (25 points) Consider a uniformly doped silicon pn junction with doping concentrations Na = 5×1015 cm–3 and Nd = 1×1016 cm–3. Determine: Vbi at T = 300 K. (5 points) xn at zero bias V = 0 V. (7 points) xn at reverse bias VR = 2 V. (5 points) The junction capacitance if the junction area is 1×10–4 cm2 and at zero bias V = 0 V and at reverse bias VR = 2 V. (8 points) e = 1.60×10–19 C, k = 8.62×10–5 eV/K, ni = 1.5×1010 cm–3 at 300 K,

Question 1: (25 points) Consider a n-type silicon wafer with a donor concentration of Nd = 1×1015 atoms/cm3 and Na = 0. Take the bandgap of silicon as 1.12 eV, NC = 2.80×1019 cm–3, NV = 1.04×1019 cm–3. To simplify the calculation, you can assume that these three values are all temperature independent. For the same reason, let’s assume that the electrons and holes obey the Boltzmann distribution. The Boltzmann constant is 1.38×10–23 J/K or 8.62×10–5 eV/K, and 1 eV = 1.60×10–19 J. Determine the temperature at which the intrinsic carrier concentrations is equal to the extrinsic electron concentration. (10 points) Determine the Fermi energy EF in EC – EF at 300 K for the n-type silicon assuming complete ionization of the donors. (5 points) Calculate the electron and hole concentrations at 700 K. You need the result from part (a) to determine which equations to use for this temperature. (10 points)

What is the 2’s complement representation of the 8-bit binary number 10110100?

Which of the following statements about loops in C++ is true?

A good business plan leads to a successful company when the entrepreneur and management team

A document that states the principles intended to guide a family firm through times of crisis and change, including the succession process, is called the:

The ______________ of a business plan identifies each of the succeeding sections and their page numbers.

In-laws not working in the family business may have a bad attitude about the company because of only hearing one side of an argument.

Deviating significantly from the standard business plan format is a mistake because: