Semiconductors and Diodes

If for a silicon npn transistor, the base-to-emitter voltage (V_BE) is 0.7 V and the collector-to-base voltage (V_CB) is 0.2 V, then the transistor is operating in the

Consider an abrupt p - n junction. Let V_bi be the built-in potential of this junction and V_R be the applied reverse bias. If the junction capacitance (C_j) is 1 pF for V_bi + V_R = 1 V, then for V_bi + V_R = 4 V, C_j will be

The drain of an n-channel MOSFET is shorted to the gate so that V_GS = V_DS. The threshold voltage (V_T) of the MOSFET is 1 V. If the drain current (I_D) is 1 mA for V_GS = 2 V, then for V_GS = 3 V, I_D is

The resistivity of a uniformly doped n −type silicon sample is 0.5 ظ - mc. If the electron mobility ($\mu_0$) is 1250 cm² / V-sec and the charge of an electron is 1.6 x 10^-19 Coulomb, the donor impurity concentration (N_D) in the sample is

If P is Passivation, Q is n-well implant, R is metallization and S is soruce/drain diffusion, then the order in which they are carried out in a standard n-well CMOS fabrication process, is

At 300 K, for a diode current of 1 mA, a certain germanium diode requires a forward bias of 0.1435V, whereas a certain silicon diode requires a forward bias of 0.718 V. Under the conditions stated above, the closest approximation of the ratio of reverse saturation current in germanium diode to that in silicon diode is

A Silicon PN junction at a temperature of 20°C has a reverse saturation current of 10 pico-Amperes (pA). The reverse saturation current at 40°C for the same bias is approximately

The drain current of MOSFET in saturation is given by I_D = K (V_GS-V_T) where K is constant. The magnitude of the transconductance g_m is

For an n-channel enhancement type MOSFET, if the source is connected at a higher potential than that of the bulk, (i.e. V_SB > 0) the threshold voltage V_T of the MOSFET

The source of a silicon (n_i = 10¹⁰ per cm³) n – channel MOS transistor has an area of 1 sq ^{_{$\mu m$}} and a depth of 1 ^{_{$\mu m$}}. If the dopant density in the source is 10¹⁹/cm³, the number of holes in the source region with the above volume is approximately.

The measured trans conductance gm of an NMOS transistor operating in the linear region is plotted against the gate voltage VG at a constant drain voltage V_D. Which of the following figures represents the expected dependence of g_m on V_G?

A p ⁺n junction has a built-in potential of 0.8 V. The depletion layer width at a reverse bias of 1.2V is 2 $\mu$m. For a reverse bias of 7.2 V, the depletion layer width will be