In a MOS capacitor with an oxide layer thickness of 10 nm, the maximum depletion layer thickness is 100 nm. The permittivities of the semiconductor and the oxide layer are $${\varepsilon _s}$$ and $${\varepsilon _{os}}$$ respectively. Asuuming $${\varepsilon _s}/{\varepsilon _{ox}} = 3$$ , the ratio of the maximum capacitance to the minimum capacitance of this MOS capacitor is________

A MOSFET in saturation has a drain current of 1 mA for V_DS =0.5V. If the channel length modulation coefficient is 0.05 V^-1, the output resistance (in k$$\Omega $$) of the MOSFET is______

For the NMOSFET in the circuit shown, in the threshold voltage is V_th, where V_th>0. The source voltage V_ss is varied from 0 to V_DD. Neglecting the channel length modulation, the drain current I_D as a function of V_ss is represented by

A depletion type N -channel MOSFET is biased in its linear region for use as a voltage controlled resistor. Assume threshold voltage V_TH = -0.5 V, V_GS = 2.0 V, V_DS = 5 V, W/L=100, C_OX=10^-8 F/cm² and $${\mu _n}$$ = 800 cm²/V-s. The value of the resistance of the voltage controlled resistor (in $$\Omega $$ ) is _____.