M.Sc. (Semester III) (CBCS) Examination Oct/Nov-2017
Materials Science
MATERIALS PROCESSING
Day Date: Tuesday, 21-11-2017 Max. Marks: 70
Time: 02.30 PM to 05.00 PM
Instructions: Q.1 and Q.2 are compulsory.
Attempt any three questions from Q. 3 to Q.7.
All questions carry equal marks.
Q.1

Objective questions
Select the correct alternative:
14
06
The atmospheric pressure is equal to
760 Torr 1 Torr
7.6 Torr 76 Torr
In resistive evaporation the filaments are usually made of refractory
metals such as Tungsten or Tantalum mainly because of their
Melting point Conductivity
Ductility Hardness
DC sputtering cannot be used for deposition of
Metal Alloy
Oxide All of the above
In physisorption due to adsorption of the adsorbate moleculesthe
electronic structure of the surface atoms
Changes irrespective of the adsorbate concentration.
Does not change irrespective of the adsorbate concentration
Changes respect to the adsorbate concentration.
None of the above
The capillary nucleation theory considers the
Interface energy of the film and substrate
Roughness of the substrate
Melting point of the Substrate
All of the above
The sticking coefficient depends on
Substrate temperature Substrate area
Substrate shape None of the above
Q.1 State True and False 08
McLeod gauge can be used for continuous measurement of vacuum.
MBE is a deposition technique for growing epitaxial film in ambient
condition.
Electro deposition can be used to deposit only conducting substrates.
In chemisorptions, a strong chemical bond is formed between the
adsorbate atom or molecule and the substrate.
Ion pump is noise free.
In case of MOCVD we may get carbon impurity.
Low nucleation rate results into deposition of thin film of large grain size.
Quartz crystal measures thickness by measuring change in oscillation
frequency.
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SLR-MO-529
Q.2 Write short answers:- 14
Spray pyrolysis 05
Diffusion pump 05
Ion plating 04
Q.3 Write the principles of rotary, diffusion and turbo molecular pump. 10
Explain working of piraniguage, in which vacuum range it can be used? 04
Q.4 Discuss in brief different types of CVD. 10
What are different advantages and disadvantages of CVD over PVD? 04
Q.5 Explain in detail different types of sputtering. How rf sputtering is helpful for
depositing oxide thin films.
10
Discuss importance of ALD. 04
Q.6 Discuss mechanical, electrical and optical properties of thin films. 10
Explain quartz crystal film thickness measurement. 04
Q.7 Discuss fundamentals of diffusion, further explain grain boundary and thin film
diffusion,
10
How stress is generated in thin films. 04