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For a silicon nMOS capacitor with no fixed oxide charge or charge at the oxide-silicon interface, the substrate doping Na = 1017 cm−3 and an aluminum gate (ΦM = 4.1 V). Find the flatband voltage VFB.

For a silicon nMOS capacitor with no fixed oxide charge or charge at the oxide-silicon interface, the substrate doping Na = 1017 cm−3 and an aluminum gate (ΦM = 4.1 V). Find the flatband voltage VFB.

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For a silicon nMOS capacitor with no fixed oxide charge or charge at the oxidesilicon interface, the substrate doping N a = 10 17 cm − 3 and an aluminum gate ( Φ M = 4.1 V). Find the flatband voltage V FB .

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Problem 2: MOS Areal Charge Density Consider an n+ poly-Si-gated MOS capacitor with oxide thickness x0 = 3 nm and p-type Si substrate doping NA = 1017 cm−3 maintained at T = 300 K. (Gate work function ΦM = 4.1 eV ) a) What is the flat-band voltage, VFB, of this capacitor? b) What is the threshold voltage, VT, of this capacitor? c) Write down formulae for the total areal charge density (in C/cm2 ) in the Si as a function of gate voltage, for each of the regions of operation (accumulation, depletion, and inversion). Plot the total areal charge density as a function of VG > VFB. d) Calculate the areal charge density in the Si for a gate voltage VG = VT + 1 V, and sketch the corresponding charge distribution within the MOS structure for this gate bias.

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