Question

Could i please have assistance in working out and theory for this question. Could i please get further explanation on how values are achieved with B and C Please

a) Calculate the conductivity of an intrinsic Si conductor at 27 °C if the hole mobility is 450 cm2 V1s-1 and the electron mobility is 1350 cm2 V's1. Assume an intrinsic carrier density of 1.45 x 1010 carriers/cm3 and an electron charge of -0.16 x 10-18 C. b) Using Figure 5, calculate the conductivity of the Si intrinsic conductor if the temperature is increased to 127 °C assuming the same electron and hole mobilities. (3 marks) (2 marks) c) The pure Si is doped with 4x1018 P atoms/cm3. Assuming that P is a group 5 element, calculate the conductivity of the doped Si extrinsic conductor at 27 °C if the electron mobility is 0.1 m2 V1s-1 (3 marks) d) Compare the conductivities in questions (a), (b) and (c) above. Which semi-conductor has the lowest (2 marks) resistivity? 1019 1018 1017 Ge 14 10 102 Si 1011 10 GaAs 10 1.5 2 2.5 3 3.5 1000/T (K Figure 5. Intrinsic carrier concentration as a function of temperature (T) TITT TT TTT ITT TITT Intinsic Carner Density n, (cm

Answer 1

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