Chegg Solutions for Microelectronic Circuits (Adel S Sedra, Kenneth C Smith) (Z-Library)_parte_403

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Step of 6 3.005P Convert the temperature T from centigrade to kelvins. = 273 For 27°C temperature, For 125°C temperature, = 398 K Step of 6 Consider a phosphorus-doped silicon layer with the impurity concentration of Since, this donates electrons. Here, donor concentration ND is much greater than the intrinsic concentration, n, The concentration of free electrons in the n-type silicon is, Therefore, the donor concentration is, Therefore, the concentration of majority electrons nₙ at 27°C and 125°C is Step of 6 Intrinsic concentration of silicon can be calculated as follows: (1) Here, B is material dependent constant, T is temperature in Kelvin, is energy bandgap of Si, k is Boltzmann's constant. Substitute for B 300 K for 1.12eV for for silicon, for k in equation (1). Step of 6 Under thermal equilibrium, the equation for the mass action law for the semiconductors is, Since =ND Calculate the hole concentration at T = 27°C or 300K = 10" = 10" Thus, the hole concentration P. at 27°C is Step 5 of 6 Calculate the intrinsic concentration of a material at T C or 398 K = = Step of 6 Calculate the hole concentration at T = - 125° C or 398 K P. = = = Thus, the hole concentration at 125° C is