Answer: Fraction of Empty States in GaAs at Room Temp w/E_{F} 0.1eV Below E_{c}

  • Thread starter Thread starter JoshHolloway
  • Start date Start date
  • Tags Tags
    Semiconductor
Click For Summary
SUMMARY

The discussion focuses on calculating the fraction of empty states in Gallium Arsenide (GaAs) at room temperature, specifically with the Fermi energy (E_{F}) positioned 0.1 eV below the conduction band (E_{c}). The donor state for tellurium (Te) is identified as 5.9 meV below E_{c}, with E_{c} for GaAs set at 1.42 eV. The effective density of states in the conduction band (N_{c}) is given as 1.04×1019 cm-3, and the thermal energy (kT) at 300K is 0.02585 eV. The calculation for the density of electrons in the donor energy level (n_{d}) is derived using the equation n_{d} = 1 + 0.5 exp[(E_{c}-E_{d}) - (E_{c}-E_{F})/kT], leading to a final value of n_{d} = 1.013123 cm-3.

PREREQUISITES
  • Understanding of semiconductor physics, specifically Gallium Arsenide (GaAs)
  • Familiarity with Fermi energy concepts and calculations
  • Knowledge of effective density of states (N_{c}) in semiconductors
  • Basic grasp of thermal energy calculations (kT) at room temperature
NEXT STEPS
  • Study the implications of donor states in semiconductor materials
  • Learn about the temperature dependence of Fermi energy in semiconductors
  • Explore the mathematical derivation of the density of states in conduction bands
  • Investigate the effects of different donor impurities on electronic properties of GaAs
USEFUL FOR

Students and researchers in semiconductor physics, electrical engineers working with GaAs devices, and anyone involved in the study of electronic properties of materials.

JoshHolloway
Messages
221
Reaction score
0

Homework Statement


The donor state for tellurium (Te) in GaAs is 5.9 meV below the conduction band (E=E_{c}). At room temperature, what fraction of the states are empty if the Fermi energy lies 0.1 eV below E_{c}

Homework Equations


E_{c}|_{GaAs}= 1.42eV
E_{d}=
E_{F}=
kT|_{(T=300K)}=0.02585 eV
N_{c}|_{(GaAs)} = 1.04\times10^{19}cm^{-3}

Where:
E_{d} is the Donor Energy Level
E_{f} is the Fermi Energy
T is the Temperature
k is the Wave Number
n_{d} is the Density of Electrons in the Donor Energy Level
N_{c} is the Effective Density of States in the Conduction Bandn_{d} = 1 + \frac{1}{2}exp[\frac{(E_{c}-E_{d})-(E_{c}-E_{F})}{kT}]

The Attempt at a Solution



Ok, so here goes:
n_{d} = 1 + \frac{1}{2}exp[\frac{( eV - eV) - ( eV - eV)}{0.02585eV}]

n_{d} = 1 + \frac{1}{2}exp[\frac{ eV - eV}{0.02585eV}]

n_{d} = 1 + \frac{1}{2}exp[\frac{ eV}{0.02585eV}]

n_{d} = 1 + \frac{1}{2}exp[-3.64023]

n_{d} = 1 + \frac{1}{2}(0.026246)

n_{d} = 1 + (.013123)

n_{d} = 1.013123 cm^{-3}
 
Last edited:
Physics news on Phys.org
Disregard this post. Sorry.
 

Similar threads

  • · Replies 2 ·
Replies
2
Views
2K
Replies
1
Views
2K
  • · Replies 5 ·
Replies
5
Views
3K
  • · Replies 9 ·
Replies
9
Views
2K
  • · Replies 1 ·
Replies
1
Views
3K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 3 ·
Replies
3
Views
8K
  • · Replies 5 ·
Replies
5
Views
6K
  • · Replies 6 ·
Replies
6
Views
4K