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MOS capacitor. The energy band diagram for an MOS capacitor (no charges in the oxide or at the oxide/semiconductor interface) maintained at 300 K is shown below. Note that the slopes of the bands in the oxide are constant. a) (3 pts) For the pictured condition determine the gate bias VG and the operation mode of the MOS capacitor. Explain. b) (3 pts) Sketch on the semi-logarithmic plot the hole concentration [log⁡(p)] inside the semiconductor as a function of x. c) (4 pts) Determine the metal-semiconductor workfunction difference, ΦMS. Explain your steps and sketch the vacuum level. d) (4 pts) Sketch the block charge diagram and the electric field E(x) vs. x.

MOS capacitor. The energy band diagram for an MOS capacitor (no charges in the oxide or at the oxide/semiconductor interface) maintained at 300 K is shown below. Note that the slopes of the bands in the oxide are constant. a) (3 pts) For the pictured condition determine the gate bias VG and the operation mode of the MOS capacitor. Explain. b) (3 pts) Sketch on the semi-logarithmic plot the hole concentration [log⁡(p)] inside the semiconductor as a function of x. c) (4 pts) Determine the metal-semiconductor workfunction difference, ΦMS. Explain your steps and sketch the vacuum level. d) (4 pts) Sketch the block charge diagram and the electric field E(x) vs. x.

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  1. (28 pts) MOS capacitor. The energy band diagram for an MOS capacitor (no charges in the oxide or at the oxide/semiconductor interface) maintained at 300 K is shown below. Note that the slopes of the bands in the oxide are constant. a) (3 pts) For the pictured condition determine the gate bias V G and the operation mode of the MOS capacitor. Explain. b) (3 pts) Sketch on the semi-logarithmic plot the hole concentration [ log ⁡ ( p ) ] inside the semiconductor as a function of x . c) (4 pts) Determine the metal-semiconductor workfunction difference, Φ M S . Explain your steps and sketch the vacuum level. d) (4 pts) Sketch the block charge diagram and the electric field E ( x ) vs. x .

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