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    Solid State Chemistry - Density, Absorption, Charge

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    1.) FREE CARRIER DENSITY
    Chemical analysis of a germanium crystal reveals indium at a level of 0.0003091 atomic percent. Assuming that the concentration of thermally excited charge carriers from the Ge matrix is negligible, what is the density of free charge carriers (free carriers/cm3) in this Ge crystal?
    2.) BORON DOPING
    Determine the amount (in grams) of boron that when substitutionally incorporated into1 kg of silicon will establish a charge carrier density of 3.091×1017 carriers/cm3.

    3.) H4P4: N-TYPE SILICON
    You wish to make n-type silicon.
    (a) Select all suitable dopant atoms from the following list:
    P B Mg Ga As In Sb Al Tl H

    (b) Name the majority charge carrier in the doped material.
    Holes Electrons Electron-hole pairs The dopant ion

    (c) The conduction band is at a higher energy than the valence band. True or false?
    True False

    (d) No electronic states lie between the conduction and valence bands in n-type silicon. True or false?
    True False

    4.) H4P5: ABSORPTION EDGE
    Gallium nitride (GaN) is a semiconductor with a bandgap Eg=3.2 eV. Calculate the absorption edge of GaN. Express your answer in units of m.

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    https://brainmass.com/chemistry/physical-chemistry/solid-state-chemistry-density-absorption-charge-513004

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    FREE CARRIER DENSITY
    Chemical analysis of a germanium crystal reveals indium at a level of 0.0003091 atomic percent. Assuming that the concentration of thermally excited charge carriers from the Ge matrix is negligible, what is the density of free charge carriers (free carriers/cm3) in this Ge crystal?
    Ans: Indium is a shallow acceptor in Ge. Hence density of free charge carriers = concentration of impurity in the volume of the matrix.
    Atomic volume of Ge = 13.6 cm3 mol-1
    DENSITY= 0.000003091 X (6.023 X 〖10〗^23)/(1 MOL) X (1 MOL)/〖13.6 CM〗^3 ...

    Solution Summary

    The expert examines solid state chemistry for density, absorption and charge.

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