Q1:

An n⁺-n Silicon device is fabricated with uniform and non-degenerate donor doping concentrations of $N_{D_1}$= 1 × 10¹⁸ cm^–3 and $N_{D_2}$= 1 × 10¹⁵ cm^–3 corresponding to the n⁺ and n regions respectively. At the operational temperature T, assume complete impurity ionization, kT/q = 25 mV, and intrinsic carrier concentration to be n_i = 1 × 10¹⁰ cm^–3. What is the magnitude of the built-in potential of this device?

Q2:

Group-I lists four different semiconductor devices. Match each device in Group-I with its characteristic property in Group-II

Group-I		Group-II
P	BJT	1	Population Incision
Q	MOS Capacitor	2	Pinch-off voltage
R	LASER diode	3	Early Effect
S	JFET	4	Flat-band voltage

 

Q3:

Contact potential of diode with temperature

Q4:

When PN junction diode is forward bias then its depletion layer width.

Q5:

Contact potential for ‘si’ diode

Q6:

Depletion layer consists of :-

Q7:

Before power amplifiers, the amplification of audio signal is done by

Q8:

In switching diode fabrication dopant is introduced into silicon which introduces additional trap level in the material there by reducing the mean life of carriers. This dopant is 

Q9:

Find the forward current of a Ge diode operating at 300k with forward voltage of 100mv across it. Assume saturation current of 20𝜇a

Q10:

Find the value limiting resistance (R_s) required for the LED circuit is given below

 

Q11:

An ideal op- amp is a

Q12:

The ideal op-amp has the following characteristics.

Q13:

When a step- input is given to an op-amp integrator, the output will be

Q14:

For an op-amp having differential gain Av and common-made gain Ac, the CMRR is given by

Q15:

In depletion MOSFET, the channel is

Q16:

An n - channel JFET has I_DSS = 2mA and V_p = – 4V. Its thermo conductance gm=in (in mA/V) for an applied GATE to voltage V_GS of – 2V is

Q17:

Consider an ideal n-channel MOSFET with parameters L = 1.25 µ_n, µ_n = 650 cm²/V-s, C_ox = 6.9 × 10^–8 F/cm², and V_T = 0.65 V. If V_GS = 5V and I_D(sat) = 4 mA then channel width will be?

Q18:

The source of a silicon (n_i = 10¹⁰ per cm³) n - channel MOS transistor has an area of 1 sq µm and a depth of 1 µm. If the dopant density in the source is 10¹⁹ / cm³, the number of holes in the source region with the above volume is approx.

Q19:

The emitter is always forward biased with respect to base?

Q20:

The lowest output impedance is obtained in case of BJT amplifiers for