1

GATE ECE 2017 Set 1

Numerical

+2

-0

The dependence of drift velocity of electrons on electric field in a semiconductor is shown
below. The semiconductor has a uniform electron concentration of n = 1x10

^{16}$$cm^{-3}$$ and electronic charge q = 1.6x10^{-19}C. If a bias of 5V is applied across a 1 $$\mu$$m region of this semiconductor, the resulting current density in this region, in kA/cm^{2}, is _________.Your input ____

2

GATE ECE 2015 Set 2

Numerical

+2

-0

A dc voltage of 10V is applied across an n–type silicon bar having a rectangular cross–section
and a length of 1cm as shown in figure. The donor doping concentration N

_{D}and the mobility of electrons $$\mu$$n are $$10^{16}$$ cm^{-3}and 1000 cm^{2}V^{-1}s^{-1}, respectively. The average time (in $$\mu$$s) taken by the electrons to move from one end of the bar to other end is _______________.Your input ____

3

GATE ECE 2014 Set 4

Numerical

+2

-0

Consider a silicon sample doped with N

_{D}= 1×10^{15}/cm^{3}donor atoms. Assume that the intrinsic carrier concentration n_{i}= 1.5×10^{10}/cm^{3}. If the sample is additionally doped with N_{A}= 1×10^{18}/cm^{3}acceptor atoms, the approximate number of electrons/cm^{3}in the sample, at T=300 K, will be _________________.Your input ____

4

GATE ECE 2014 Set 4

MCQ (Single Correct Answer)

+2

-0.6

An N-type semiconductor having uniform doping is biased as shown in the figure.

If E_{C} is the lowest energy level of the conduction band, E_{V} is the highest energy level of the
valance band and E_{F} is the Fermi level, which one of the following represents the energy
band diagram for the biased N-type semiconductor?

Questions Asked from Semiconductor Physics (Marks 2)

Number in Brackets after Paper Indicates No. of Questions

GATE ECE Subjects

Network Theory

Control Systems

Electronic Devices and VLSI

Analog Circuits

Digital Circuits

Microprocessors

Signals and Systems

Representation of Continuous Time Signal Fourier Series
Discrete Time Signal Fourier Series Fourier Transform
Discrete Time Signal Z Transform
Continuous Time Linear Invariant System
Transmission of Signal Through Continuous Time LTI Systems
Discrete Time Linear Time Invariant Systems
Sampling
Continuous Time Signal Laplace Transform
Discrete Fourier Transform and Fast Fourier Transform
Transmission of Signal Through Discrete Time Lti Systems
Miscellaneous
Fourier Transform

Communications

Electromagnetics

General Aptitude