- Draw an MOS flatband diagram. Indicate the workfunction of the metal and the semiconductor as well as the flatband voltage. Draw it approximately to scale using FM = 4.1 V, c = 4.05 V, Eg = 1.12 eV (silicon) and Na = 1016 cm-3.
- Derive the metal-semiconductor workfunction for n-type and p-type poly-silicon gate structures. (equation 6.3.2)
- Explain why the flatband voltage depends on the charge in the oxide or at the oxide-semiconductor interface.
- Name the three bias regimes of an MOS capacitor and explain what happens in the semiconductor in each of these bias modes.
- What is the basic assumption regarding the charge in the inversion layer?
- What are the assumptions of the MOS capacitor analysis?
- What is the difference between the high frequency and quasi-static capacitance?
- Why is the high frequency capacitance constant in inversion?
- Why does the flatband capacitance not equal the oxide capacitance?
- What is deep depletion?
- Why does light illumination affect the capacitance of an MOS structure?
- Name the non-ideal effects in MOS capacitors. What causes them and how do they affect the MOS characteristics?
|