Register

Recent questions tagged carrier-transport

1 1 vote
1 1 answer
613
613 views
GATE ECE 2006 | Question: 8
The concentration of minority carriers in an extrinsic semiconductor under equilibrium isdirectly proportional to the doping concentrationinversely proportional to the do...
0 0 votes
0 0 answers
429
429 views
GATE ECE 2006 | Question: 38
The majority carriers in an $n$-type semiconductor have an average drift velocity $\mathrm{V}$ in a direction perpendicular to a uniform magnetic field $\text{B}.$ The el...
0 0 votes
1 1 answer
711
711 views
GATE ECE 2006 | Question: 40
A heavily doped $n$-type semiconductor has the following dataHole-electron mobility ratio : $0.4$Doping concentration : $4.2 \times 10^{8} \; \mathrm{atoms/m}^{3}$Intrins...
0 0 votes
0 0 answers
295
295 views
GATE ECE 1994 | Question 1.7
A small concentration of minority carries is injected into a homogeneous semiconductor crystal at one point. An electric field of $10 \mathrm{~V} . \mathrm{cm}$ is applie...
0 0 votes
0 0 answers
317
317 views
GATE ECE 1994 | Question 2.8
The transit time of the current carriers through the channel of an $\text{FET}$ decides its _________ chracteristics.
0 0 votes
0 0 answers
197
197 views
GATE ECE 1994 | Question 3.4
A $p$-type silicon sample has a higher conductivity compared to an $n$-type sample having the same dopant concentration.
1 1 vote
1 1 answer
817
817 views
GATE ECE 2007 | Question: 9
The electron and hole concentrations in an intrinsic semiconductor are $n_i$ per $\mathrm{cm}^3$ at $300 \mathrm{~K}$. Now, if acceptor impurities are introduced with a c...
1 1 vote
0 0 answers
455
455 views
GATE ECE 2008 | Question: 18
A silicon wafer has $100 \mathrm{~nm}$ of oxide on it and is inserted in a furnace at a temperature above $1000^{\circ} \mathrm{C}$ for further oxidation in dry oxygen. T...
1 1 vote
0 0 answers
255
255 views
GATE ECE 2008 | Question: 51
Silicon is doped with boron to a concentration of $4 \times 10^{17}$ atoms $/ \mathrm{cm}^{3}$. Assume the intrinsic carrier concentration of silicon to be $1.5 \times 10...
1 1 vote
0 0 answers
381
381 views
GATE ECE 2009 | Question: 5
In an n-type silicon crystal at room temperature, which of the following can have a concentration of $4 \times 10^{19} \mathrm{~cm}^{-3}$ ?Silicon atomsHolesDopant atomsV...
1 1 vote
0 0 answers
543
543 views
GATE ECE 2009 | Question: 15
The ratio of the mobility to the diffusion coefficient in a semiconductor has the units$\mathrm{V}^{-1}$$\mathrm{cm} \cdot \mathrm{V}^{-1}$$\mathrm{V} \cdot \mathrm{cm}^{...
1 1 vote
0 0 answers
511
511 views
GATE ECE 2009 | Question: 32
Consider the following two statements about the internal conditions in an n-channel MOSFET operating in the active region.$\qquad \qquad \text{S1:}$ The inversion charge ...
1 1 vote
0 0 answers
216
216 views
GATE ECE 2010 | Question: 6
At room temperature a possible value for the mobility of electrons in the inversion layer of a silicon $n$-channel MOSFET is$450 \text{ cm}^2 / \text{V-s}$$1350 \text{ cm...
1 1 vote
0 0 answers
316
316 views
GATE ECE 2010 | Question: 52
The silicon sample with unit cross-sectional area shown below is in thermal equilibrium. The following information is given: $\text{T}=300 \mathrm{~K}$, electronic charge...
1 1 vote
0 0 answers
423
423 views
GATE ECE 2010 | Question: 53
The silicon sample with unit cross-sectional area shown below is in thermal equilibrium. The following information is given: $\text{T}=300 \mathrm{~K}$, electronic charge...
0 0 votes
0 0 answers
572
572 views
GATE ECE 1992 | Question 1.11
A semiconductor is irradiated with light such that carriers are uniformly generated throughout its volume. The semiconductor is $n$-type with $N_{D}=10^{19}$ per $\mathrm...
0 0 votes
0 0 answers
336
336 views
GATE ECE 1991 | Question 1.14
A silicon sample is uniformly doped with $10^{16}$ phosphorous atoms $/ \mathrm{cm}^3$ and $2 \times 10^{16}$ boron atoms $/ \mathrm{cm}^3$. If all the dopants are fully ...
0 0 votes
0 0 answers
554
554 views
GATE ECE 1991 | Question 1.15
An $n$-type silicon sample, having electron mobility $\mu_n=$ twice the hole mobility $\mu_p$, is subjected to a steady illumination such that the electron concentration ...
0 0 votes
0 0 answers
317
317 views
GATE ECE 1991 | Question 4
The current $I$ in a forward biased $P^{+} N$ junction shown in figure (a) is entirely due to diffusion of holes from $x=0$ to $x=L$. The injected hole concentration dist...
1 1 vote
0 0 answers
411
411 views
GATE ECE 2011 | Question: 21
Drift current in semiconductors depends upononly the electric fieldonly the carrier concentration gradientboth the electric field and the carrier concentrationboth the el...
0 0 votes
0 0 answers
704
704 views
GATE ECE 2022 | Question: 6
Consider a long rectangular bar of direct bandgap $p-$type semiconductor. The equilibrium hole density is $10^{17} \; \text{cm}^{-3}$ and the intrinsic carrier concentrat...
User Avatar
0 0 votes
0 0 answers
800
800 views
GATE ECE 2022 | Question: 7
In a non-degenerate bulk semiconductor with electron density $n = 10^{16} \; \text{cm}^{-3},$ the value of $E_{c} – E_{Fn} = 200 \; \text{meV},$ where $E_{c}$ and $E_{Fn}...
User Avatar
0 0 votes
0 0 answers
725
725 views
GATE ECE 2022 | Question: 46
A $p-$type semiconductor with zero electric field is under illumination (low level injection) in steady state condition. Excess minority carrier density is zero at $x = \...
User Avatar
0 0 votes
0 0 answers
884
884 views
GATE ECE 2021 | Question: 6
​​​​​​A bar of silicon is doped with boron concentration of $10^{16} \text{cm}^{-3}$ and assumed to be fully ionized. It is exposed to light such that electron-hole pairs...
User Avatar
0 0 votes
0 0 answers
628
628 views
GATE ECE 2021 | Question: 7
The energy band diagram of a $\text{p-type}$ semiconductor bar of length $L$ under equilibrium condition (i.e.. the Fermi energy level $E_{F}$ is constant) is shown in th...
User Avatar
0 0 votes
0 0 answers
749
749 views
GATE ECE 2019 | Question: 41
The $\text{RC}$ circuit shown below has a variable resistance $R(t)$ given by the following expression:$$R(t)=R_{0}\left(1-\frac{t}{T}\right) \text{for} \:\: 0 \leq t < T...
User Avatar
0 0 votes
0 0 answers
590
590 views
GATE ECE 2016 Set 3 | Question: 33
In the figure shown, the current $i$ (in ampere) is _________
0 0 votes
0 0 answers
581
581 views
GATE ECE 2015 Set 1 | Question: 24
Consider a straight, infinitely long, current carrying conductor lying on the z-axis. Which one of the following plots (in linear scale) qualitatively represents the depe...
0 0 votes
0 0 answers
725
725 views
GATE ECE 2012 | Question: 53
An infinitely long uniform solid wire of radius $a$ carries a uniform dc current of density $\overrightarrow{j}$.A hole of radius $b$ (b < a) ia now drilled along the len...
0 0 votes
0 0 answers
377
377 views
GATE ECE 2012 | Question: 52
An infinitely long uniform solid wire of radius $a$ carries a uniform dc current of density $\overrightarrow{j}$.The magnetic field at a distance $r$ from the center of t...
Page: