Transcribed TextTranscribed Text

2.(i) How many atoms are present in a unit cell of a BCC lattice? (ii) Find the volume density ofatoms of the BCC lattice if lattice constant is 5 Å. [2+8=10] 3. (i) Prove the lattice constant of a FCC lattice is 𝑎 =2√2𝑟 where r is the atomic radius. (ii) If the atomic radius for a FCC lattice is 0.175nm, find the volume of the unit cell. [6+4=10] 4. Find out the atomic packing factor of a BCC crystal lattice whose lattice constant is ‘a’. [10] 5. Find out the Miller Indices of the following. [5x4=20] (i) (ii) (iii) (iv) (v) 6 6.Find out the (i) momentum and (ii) de-Broglie wavelength of an electron travelling with avelocity of 107 cm/s. Consider mass of electron as 9.1×10-31 Kg. [5+5=10] 7. Determine the probability that an energy level 3KT above Fermi level is occupied by an electron at T = 300 K. [Hint: Difference between E and EF is 3KT] [10] 8. Calculate the (i) probability that a state in the conduction band is occupied by an electron f(EC) and calculate the (ii) thermal equilibrium electron concentration (n0) in silicon at T= 100 K. Assume the Fermi energy is 0.25 eV below the conduction band. The value of NC for silicon at T = 100 K is 2.8 x I019 cm-3. [5+5 = 10] 9. Calculate the intrinsic carrier concentration in gallium arsenide at T = 300 K. The values of NC and NV at 300 K for gallium arsenide are 4.7 x 1017 cm-3 and 7.0 x 1018 cm-3, respectively. Assume the bandgap energy of gallium arsenide is 1.42 eV.

Solution PreviewSolution Preview

These solutions may offer step-by-step problem-solving explanations or good writing examples that include modern styles of formatting and construction of bibliographies out of text citations and references. Students may use these solutions for personal skill-building and practice. Unethical use is strictly forbidden.

    By purchasing this solution you'll be able to access the following files:

    for this solution

    or FREE if you
    register a new account!

    PayPal, G Pay, ApplePay, Amazon Pay, and all major credit cards accepted.

    Find A Tutor

    View available Semiconductor Physics Tutors

    Get College Homework Help.

    Are you sure you don't want to upload any files?

    Fast tutor response requires as much info as possible.

    Upload a file
    Continue without uploading

    We couldn't find that subject.
    Please select the best match from the list below.

    We'll send you an email right away. If it's not in your inbox, check your spam folder.

    • 1
    • 2
    • 3
    Live Chats