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A MOSFET is fabricated with the work function difference ϕMS = −0.46 V, the fixed charge QF/q = 2×1011 /cm2, the mobile charge QM = 0, and the interface charge QIT = 0, the oxide thickness xo = 0.05 μm, the gate area AG = 10−3 cm2, and the substrate doping concentration ND = 1015 /cm3. QI/q = 4×1011 /cm2 is the ion charge implanted immediately adjacent to the Si−SiO2 interface to adjust the threshold voltage VT. (a) Determine VFB. (b) Determine VT. (c) Is the given MOSFET an enhancement mode or depletion mode device? Explain.

A MOSFET is fabricated with the work function difference ϕMS = −0.46 V, the fixed charge QF/q = 2×1011 /cm2, the mobile charge QM = 0, and the interface charge QIT = 0, the oxide thickness xo = 0.05 μm, the gate area AG = 10−3 cm2, and the substrate doping concentration ND = 1015 /cm3. QI/q = 4×1011 /cm2 is the ion charge implanted immediately adjacent to the Si−SiO2 interface to adjust the threshold voltage VT. (a) Determine VFB. (b) Determine VT. (c) Is the given MOSFET an enhancement mode or depletion mode device? Explain.

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A MOSFET is fabricated with the work function difference ϕ M S = − 0.46 V , the fixed charge Q F / q = 2 × 10 11 / c m 2 , the mobile charge Q M = 0 , and the interface charge Q I T = 0 , the oxide thickness x o = 0.05 μ m , the gate area A G = 10 − 3 c m 2 , and the substrate doping concentration N D = 10 15 / c m 3 . Q I / q = 4 × 10 11 / c m 2 is the ion charge implanted immediately adjacent to the S i − S i O 2 interface to adjust the threshold voltage V T . (a) Determine V F B . (b) Determine V T . (c) Is the given MOSFET an enhancement mode or depletion mode device? Explain.

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