Download AKTU (Dr. A.P.J. Abdul Kalam Technical University (AKTU), formerly Uttar Pradesh Technical University (UPTU) B-Tech 6th Semester (Sixth Semester) 2015-2016 EEC 013 Advanced Semiconductor Devices Question Paper
(Following Paper ID and Roll No. to be ?lled in your
Answer Books)
PaperID:131653 R011N0.| I I I I I | | | |
B.TECH.
Theory Examination (Semester?VI) 2015-16
ADVANCED SEMICONDUCTOR DEVICES
Time : 3 Hours Max. Marks : 100
Section-A
1. Attempt all parts. All parts carry equal marks. Write
answer of each part in short. (2X10=20)
(a) The Si energy gap changes monotonically with tempera-
ture. What is the basic concept behind this?
(b) Draw the energy level diagram of a PN junction.
(C) HOW a junction barrier is developed across an unbiased
junction?
(d) Make the energy band diagram of a metal and semicon-
ductor junction at equilibrium. Consider Al metal having
a large work function and n?type semiconductor.
1 (1) P.T.O.
(e)
(f)
(g)
(h)
(i)
0)
Why does current saturate in long channel MOSFET
When large drain voltage is applied on drain?
A pn junction photodiode is operated under photovol-
taic condition similar to solar cell and having the similar
I-V Characteristics. under illumination. State three ma-
jor differences between photodiode and solar cell.
What is kinetic energy of a hole at the top of the valence
band?
De?ne minority carrier life time.
What are the different types of degenerate Semiconduc-
tors?
What is meant by IMPATT diode?
Section-B
Attempt any ?ve questions from this section. (10X5=50)
(a)
(i) Explain the recombination of excess carriers in semi-
conductors. Derive an expression for excess carrier
lifetime.
(i1) Derive an expression for hole and electron di?usion
current.
(2) P.T.O.
(b)
Prove that for a linearly graded PN junction the maxi-
mum electric ?eld in depletion region is 3/2 times of
average electric ?eld.
(0) Derive the current expression for long base ideal diode.
(d) Write down the different methods to calculate the
barrier height of a Schottky barrier diode.
(e) Explain the formation of rectifying M-S contact barrier
process using Schottky?Mott theory.
(f) Derive an expression for a saturated drain current of a
n?channel ME SFET.
(g) Explain the principle of operation, storage and transfer
of charge in basic charge coupled device (CCD).
(h) Derive an expression for power output and e?iciency of
a MSM BAITT diode.
Section-C
Attempt any two questions from this section. (15X2=30)
3. The donor and acceptor concentration in Si sample is 6><1015
and 2><1015 cm?3 respectively. Determine the position ofFermi
(3) P.T.O.
Level With recpect to intrinsic energy level Ei at room tem-
perature. Also ?nd out the value and sign of Hall coe?icient.
Explain the MESGET operation in case of Depletion mode
and enhancement mode device. Draw the I-V characteristic
also.
A hetero-junction is formed between n-type Ge
(With Nd=1.5><1016 cm?3) and p-type GaAs (With
Na=8.5><1015 cm3).
i. Draw the thermal equilibrium energy band diagram of
junction.
ii Calculate the buit?in voltage of the junction.
(4) P.T.O.
This post was last modified on 29 January 2020