PYQs Based Test - 13 : Electronic Devices

The doping concentrations on the p-side and n-side of a silicon diode are 1 × 10¹⁶ cm⁻³ and 1 × 10¹⁷ cm⁻³, respectively. The forward bias of 0.3 V is applied to the diode. At T = 300 K, the intrinsic carrier concentration of silicon nᵢ = 1.5 × 10¹⁰ and $\frac{kT}{q}=26mV$. The electron concentration at the edge of the depletion region p-side is

The slope of the I${}_D$ vs. V${}_{GS}$ curve of an n-channel MOSFET in linear regime is 10⁻³ Ω⁻¹ at V${}_{DS}$ = 0.1 V. For the same device, neglecting channel length modulation, the slope of the $\sqrt{I_D}$ vs. V${}_{GS}$ curve (in $\sqrt{A}/V$) under saturation regime is approximately ______

The quantum efficiency (η) and responsivity (R) at a wavelength λ (in μm) in a p-i-n photodetector are related by

A silicon P-N junction is shown in the figure. The doping in the P region is 5 × 10¹⁶ cm⁻³ and doping in the N region is 10 × 10¹⁶ cm⁻³. The parameters given are

Built-in voltage (Φ${}_{bi}$) = 0.8 V

Electron charge (q) = 1.6 × 10⁻¹⁹ C

Vacuum permittivity (ε₀) = 8.85 × 10⁻¹² F / m

Relative permittivity of silicon (ε${}_{Si}$) = 12



The magnitude of reverse bias voltage that would completely deplete one of the two regions (P or N) prior to the other (rounded off to one decimal place) is _______ V.

As shown, two Silicon (Si) abrupt p-n junction diodes are fabricated with uniform donor doping concentrations of N${}_{D1}$ = 10¹⁴ cm${}^{\text{–}3}$ and N${}_{D2}$ = 10¹⁶ cm${}^{\text{–}3}$ in the n-regions of the diodes, and uniform acceptor doping concentrations of N${}_{A1}$ = 10¹⁴ cm${}^{\text{–}3}$ and N${}_{A2}$ = 10¹⁶ cm${}^{\text{–}3}$ in the p-regions of the diodes, respectively. Assuming that the reverse bias voltage is ≫ built-in potentials of the diodes, the ratio C₂/C₁ of their reverse bias capacitances for the same applied reverse bias, is ________.