Give formation and applications of SQUID.
[3 marks]Explain intrinsic and extrinsic semiconductors with necessary diagram.
[4 marks]What is PN junction diode? What is external bias? Describe its forward and reverse bias conditions with appropriate diagram.
[7 marks]What is photo conductivity, photoluminescence, phototransistor?
[3 marks]Calculate the energy gap of Si, given that radiation of wavelength 11,000 Å is incident on it. Also find allowed wavelength for Ge with energy gap 0.90 eV.
[4 marks]Write a note on energy band diagram and formation of energy bands.
[7 marks]Define Hall effect and Hall coefficient. Derive equation to find Hall voltage. What does it signify?
[7 marks]Differentiate between soft and hard superconductors
[3 marks]What is London penetration depth? Derive its equations.
[4 marks]Derive equations for n-type semiconductor to determine dependence of fermi level on temperature and doping concentration.
[7 marks]The critical current density equal to 1.71 x 108 A/m2 is required to change a superconducting wire of radius 0.5 mm at 4.2 K. If the critical temperature of the material is 7.18 K, calculate the maximum value of the critical magnetic field.
[3 marks]Explain BCS theory for superconductivity.
[4 marks]Write a note on metal semiconductor junctions.
[7 marks]Write a note on exciton.
[3 marks]Give details of applications of solar cell (at least 4)
[4 marks]What is radiative and non-radiative transition. Explain in brief the optical joint density of states.
[7 marks]What are direct and indirect band gap?
[3 marks]What is deep level transient spectroscopy (DLTS)? Give its experimental procedure.
[4 marks]Discuss the technique to obtain band gap by UV-Vis spectroscopy using absorption or transmission.
[7 marks]What are capacitance voltage measurements?
[3 marks]Consider n-type silicon semiconductor with a length of 100 μm, cross sectional area 10-7 cm2, minority charge carrier life time 10-6 s, μ is 0.13 e m2 / Vs and μ is 0.05 m2 / Vs. h Find (a) Electron transit time1
[4 marks]Photo conductor gain when voltage applied to the photoconductor is 12 V
[ marks]Discuss Van Der Pauw method.
[7 marks]What is the cause and remedy for optical loss in photovoltaic cell?
[3 marks]State principle and discuss working of semiconductor laser.
[4 marks]What is photovoltaic effect? Explain construction and working of a solar cell with suitable diagram
[7 marks]