M.Sc. (Semester III) (CBCS) Examination Mar/Apr-2018
Physics (Materials Science)
MATERIALS PROCESSING
Time: 2½ Hours
Max. Marks: 70
Instructions: Q.1 and Q.2 are compulsory. Attempt any three questions from Q. 3 to 7. All questions carry equal marks.
Q.1

Choose the correct alternative:
06
DC sputtering cannot be used for deposition of
Metal
Alloy
Oxide
All above
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
The atmospheric pressure is equal to
760 Torr
1 Torr
7.6 Torr
76 Torr
In physisorption due to adsorption of the adsorbate molecules the electronic structure of the surface atoms
Changes irrespective of the adsorbate concentration
Does not change irrespective of the adsorbate concentration
Changes with respect to the adsorbate concentration
None of the above
The sticking coefficient depends on
Substrate temperature
Substrate area
Substrate shape
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

State True or False/ Fill in the blanks:
08
Ion pump is noise free.
Low nucleation rate results into deposition of thin film of large grain size.
Quartz crystal measures thickness by measuring change in oscillation frequency.
Electrodeposition can be used to deposit only conducting substrates.
MBE is a deposition technique for growing epitaxial film in ambient condition.
In chemisorption, a strong chemical bond is formed between the adsorbate atom or molecule and the substrate.
In case of MOCVD we may get carbon impurity.
McLeod gauge can be used for continuous measurement of vacuum.
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Q.2
Write a short note on:
Plasma enhanced CVD
05
Titanium sublimation pump
05
Grain boundary diffusion
04
Q.3
Write the principles of rotary, diffusion and turbo molecular pump.
10
Explain working of penning guage, in which vacuum range it can be used?
04
Q.4
Discuss mechanical, electrical and optical properties of thin films.
10
Explain quartz crystal film thickness measurement.
04
Q.5
Explain in detail different types of sputtering. How AC sputtering is helpful for depositing oxide thin films?
10
Discuss spray pyrolysis.
04
Q.6
Discuss in brief different types of CVD.
10
What are different advantages and disadvantages of CVD over PVD?
04
Q.7
Discuss fundamentals of diffusion, further explain grain boundary and thin film diffusion.
10
How stress is generated in thin films?
04