These movies were created using the animation feature of Mathcad and are quantitatively correct.
Band diagram of an ideal MOS capacitor
This animation shows the band diagram of an ideal MOS capacitor. The insulator is SiO2 1000 A thick and simulations for two different substrate concentrations (NA=1015 cm-3 and 1016 cm-3) are provided. The surface potential and actual gate voltage are indicated.
doping of 1015 cm-3
doping of 1016 cm-3
This animation shows the band diagram and low-frequency C(V) characteristic of an MOS capacitor. The insulator is SiO2 1000 A thick and simulations for two different substrate concentrations (NA=1015 cm-3 and 1016 cm-3) are provided.
The capacitances shown are in farads/cm2. The insulator capacitance is nearly full scale on the capacitance plot.
doping of 1015 cm-3
doping of 1016 cm-3
This animation shows the carrier concentrations in the MOS capacitor as a function of surface potential. The behavior shown in the animation would be observed for a very slow sweep from accumulation to inversion. Also illustrated is the electric field as a function of position and the potential as a function of position.
You can manually move the slider to examine more carefully the effect of different surface potentials.
The simulations have been done for substrate concentrations of 1015 cm-3 and 3x1015 cm-3. The distance scales are unchanged to facilitate comparison. Note, however, that the carrier concentration scale (only) has been changed.
doping of 1015 cm-3
doping of 1016 cm-3
This animation shows the relaxation of an MOS capacitor which has been pulsed into deep depletion. The band diagram is shown as a function of time and the variation in the capacitance is plotted simultaneously.
The capacitor has a substrate doping of 1015 cm-3 and the insulator is SiO2 1000 A thick. It is assumed that generation through interface states can be neglected (s=0). The time scale is in arbitrary units. Two simulations are shown for different bias voltages.
relaxation from a small depletion bias (VG=VFB+2.5 V)
relaxation from a larger depletion bias (VG=VFB+5 V)
transfer of a large charge packet
transfer of a small charge packet
surface potentials as a function of time in a two-phase CCD
illustration of operation of an input stage (3-phase CCD)