Question

59 If we decrease the substrate doping concentration, how will the following parameters be affected? (Please indicate your answer by putting a mark, X, in the correct column.) Write down any relevant equation and explain briefly how you obtain the answer (a few words or one sentence). Assume the gate material is N poly and the body is P type. Increase Decrease Unchanged Parameters A Accumulation region capacitance B Flat-band voltage, Vib C Depletion-region capacitance D Threshold voltage. V E Inversion region capacitance

Answer 1

decreases substrate daping concentration Accumulation region capacitance Ca EnEXA dd substrate doping substrate accumulation region doping width concentration decreases increases, capacitance decreases. o flat Band voltage Amsterdam en die tare which is independent on substrate doping © Depletion region capacitance ca el (a box = Ve wa Zests veve 40 สๆ Doping decreases capacitance decreases

@ threshold voltage. NSB = Vot . 20F 28 Cose Doping decreases thereshold voltage decrecues. © inversion region capacitance Pnv = Core CVq-vr) lox = V-Vt filled inversian layer with inversion Electrona Doping decrease V deceases Coy decreases.