Download AKTU B-Tech 6th Sem 2017-2018 NEC 603 Integrated Circuit Technology Question Paper

Download AKTU (Dr. A.P.J. Abdul Kalam Technical University (AKTU), formerly Uttar Pradesh Technical University (UPTU) B-Tech 6th Semester (Sixth Semester) 2017-2018 NEC 603 Integrated Circuit Technology Question Paper

Printed pages: 02 Sub Code: NEC 603
Paperld: RollNo=| | | | | | | | | | |
B TECH
(SEM-VI) THEORY EXAMINATION 2017-18
INTEGRATED CIRCUIT TECHNOLOGY
T ime: 3 Hours T otal Marks: 100
Note: 1. Attempt all Sections. If require any missing data; then choose suitably.
SECTION A
1. Attempt all questions in brief. 2 x10 = 20
What are point defects?
List the steps used in the preparation of Si ? wafers.
What do you mean by $01?
Define the process of oxidation .List two important properties of SiOz.
Explain isotropic & anisotropic etching processes.
What is metallization?
What is the difference between pseudo homo epitaxy and hetero epitaxy?
What is step coverage problem in IC fabrication?
What are the advantages of ion implantation technique?
Explain basic differences between Bipolar and MOS Integrated Circuits
Hewqorbrvp-ozcrw
SECTION B
2. Attempt any three of the following: 10 x 3 = 30
a. Describe CZ process in detail with neat diagram. What is the Pull Rate in CZ technique?
How the Pull Rate is controlled during the CZ crystal growth process?
b. Why Oxidation is necessary in IC fabrication? Calculate the oxide thickness. Show that
x t+T
A/2 _[1 +A2/4B
J B(t + T) for long time, where x = oxide thickness.
1 2
B .
1 -1, reduces to x = Z (t + 1') for short time and to x =
c. Derive the diffusion equation. How the depth of diffusion is controlled during diffusion
process? Give the solution of Fick?s Law?
(1. Explain the metallization and describe the problems associated with this process. Explain
dc sputtering method of metallization.
e. How a NPN transistor can be fabricated? Explain all the steps of fabrication. Also
compare it with NMOS fabrication.

4.
SECTION C
Attempt any one part of the following: 10 x 1 = 10
a. Explain the basic working principle of ion implantation process with all necessary
equations. Compare between the diffusion and ion implantation process.
b. A silicon ingot with 0.5x1016 boron atoms/cm3 is to be grown by CZ method. What
should be the concentration of boron in the melt to obtain the required doping
concentration? The segregation coefficient of the boron is 0.8.
Attempt any one part of the following: 10 x 1 = 10
What is Epitaxy? Discuss Molecular Beam Epitaxy technique in brief. What are the
advantages of MBE over VPE?
. What do you mean by film deposition? Explain different types of films deposited in IC
fabrication.
Attempt any one part of the following: 10 x 1 = 10
Explain the following terms: (i) Self Aligned Bipolar structures (ii) Integrated Injection
Logic.
. Explain proximity printing and projection printing & compare these two.
Attempt any one part of the following: 10 x 1 = 10
(i)Exp1ain the kinetics of wet etching. How gold is etched?
(ii) What are PR materials? What are the properties of different PR?
. If the measured phosphorus pro?le is represented by a Gaussian function with a diffusivity
D =2.3x10'13 atoms/cmz, the measured surface dose is 1018 atoms/cm2 and the measured
junction depth is 1 pm at a surface concentration of 1015 atoms/cm3. Calculate the diffusion
time.
Attempt any one part of the following: 10 x 1 = 10
Write short note on package types and packaging design VLSI Technology. What is meant
by DIP? Explain in brief.
. Write short Notes on (i) Annealing (ii) Chemical Vapor deposition(CVD)