Physical constants Planks constant h=6.62607x10-34 JS Reduced planks constant h=1.05457x10-4 JS Boltzmann constant K = 1.38066x10-23J/K...

  

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Physical constants Planks constant h=6.62607x10-34 JS Reduced planks constant h=1.05457x10-³4 JS Boltzmann constant K = 1.38066x10-23J/K Electron-Volt (ev)=1.60218x10-¹9 J Elementary charge (q) = 1.60218x10-¹⁹ C Question 1 a. Distinguish between intrinsic and extrinsic semiconductors b. Using energy band diagrams, distinguish metals, insulators and semiconductors (2mks) (3mks) c. Using appropriate band diagrams differentiate between P-type and N-type semiconductors (4mks) d. A Si sample is doped with 10¹7 Arsenic atoms/cm³. Determine the equilibrium hole (P) concentration at 300K, given that the intrinsic carrier concentration of Si is n₁ = 9.65×10 cm³ (4mks) e. Using appropriate band diagram show where the Fermi level (EF) is relative to Ei. (4mks) (2mks) (2mks) f. i) Define the term noise in a semiconductor device ii) Define the term noise power spectral density g. The mobility of free electrons and holes in pure germanium are 3800 and 1800 cm²/V.S respectively. The corresponding values for pure silicon are 1300 and 500 cm²/V.S respectively. Determine the values of intrinsic conductivity for both germanium and silicon. Assume n₁ = 2.5×10¹3 cm³ for germanium and n = 1.5x100 cm3 for silicon at room temperature. (5mks) h. Differentiate between forward bias and reverse bias of a P-N junction. (4mks) Physical constants Planks constant h=6.62607x10-34 JS Reduced planks constant h=1.05457x10-³4 JS Boltzmann constant K = 1.38066x10-23J/K Electron-Volt (ev)=1.60218x10-¹9 J Elementary charge (q) = 1.60218x10-¹⁹ C Question 1 a. Distinguish between intrinsic and extrinsic semiconductors b. Using energy band diagrams, distinguish metals, insulators and semiconductors (2mks) (3mks) c. Using appropriate band diagrams differentiate between P-type and N-type semiconductors (4mks) d. A Si sample is doped with 10¹7 Arsenic atoms/cm³. Determine the equilibrium hole (P) concentration at 300K, given that the intrinsic carrier concentration of Si is n₁ = 9.65×10 cm³ (4mks) e. Using appropriate band diagram show where the Fermi level (EF) is relative to Ei. (4mks) (2mks) (2mks) f. i) Define the term noise in a semiconductor device ii) Define the term noise power spectral density g. The mobility of free electrons and holes in pure germanium are 3800 and 1800 cm²/V.S respectively. The corresponding values for pure silicon are 1300 and 500 cm²/V.S respectively. Determine the values of intrinsic conductivity for both germanium and silicon. Assume n₁ = 2.5×10¹3 cm³ for germanium and n = 1.5x100 cm3 for silicon at room temperature. (5mks) h. Differentiate between forward bias and reverse bias of a P-N junction. (4mks)