I’m analyzing the attached graph (which I wrote in Matlab), which shows the capacitance of an MOS capacitor as a function of the surface potential: $$\psi_s$$ for different temperatures. The graph displays distinct differences between the curves at various temperatures, and I want to confirm if these trends are consistent with theoretical expectations.
Questions:
- Does the shape and behavior of the capacitance vs. surface potential curves align with physical results for an MOS capacitor under varying temperatures?
- If the graph is correct, could someone explain the observed differences in capacitance as temperature changes (e.g., in terms of depletion width, carrier distribution, or other factors)?
System Parameters:
Here are the key parameters used for the analysis:
-Charge of an electron: $$q = 1.6 \times 10^{-19} \, \text{C}$$
-Boltzmann constant: $$k_B = 1.38 \times 10^{-23} \, \text{J/K}$$
-Vacuum permittivity: $$\varepsilon_0 = 8.85 \times 10^{-14} \, \text{F/cm}$$
-Relative permittivity of silicon: $$\varepsilon_{\text{Si}} = 11.8$$
-Relative permittivity of silicon dioxide: $$\varepsilon_{\text{ox}} = 3.9$$
-Doping concentration: $$N_A = 10^{15} \, \text{cm}^{-3}$$
-Oxide thickness: $$t_{\text{ox}} = 20 \, \mu\text{m}$$$$t_{\text{ox}} = 20*10^{-6} \, \text{cm}$$