Chegg Solutions for Microelectronic Circuits (Adel S Sedra, Kenneth C Smith) (Z-Library)_parte_437

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Step 1 of 4 3.028P Refer to the problem 3.22 in the textbook. A n junction is one in which doping concentration in the p-region is much greater than that of the n- region. In such a junction the forward current is mostly due to hole injection. Hence, 1=1, = Here, I is forward current and is current due to holes. Hole life time is given by, = (1) Here, L, is diffusion length of hole, D, is diffusion constant. Step 2 of 4 Substitute for L, 10 cm²/s for D, in the equation (1). = Therefore, the hole life time is t, is Step 3 of 4 The excess minority carrier charge Q is, = Substitute 10⁻⁷ S for t, , 0.1 mA for in the above equation. = Therefore, the stored minority carrier charge Q is Step 4 of 4 Diffusion capacitance Cd can be calculated as follows: Here, is thermal voltage, I, is current due to holes and t, is hole life time. Substitute S for , 0.1 mA for 26 mV for in the diffusion capacitance expression. =384.6x10⁻¹F =384.6 Therefore, the values of C, is