Band Structure of a solid is not related to the size/doping?

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SUMMARY

The discussion centers on the relationship between band structure and doping in silicon (Si) blocks. It is established that the band structure and Fermi level of a specific block of solid are unique to that block, influenced by the arrangement of positive ions and lattice imperfections. Despite variations in size and doping, the valence bands of silicon blocks remain consistent, while the density of states increases with volume. The effects of doping and potential well changes become negligible in macroscopic bodies, only requiring consideration in nanoparticles with a few hundred atoms.

PREREQUISITES
  • Understanding of band structure in solid-state physics
  • Familiarity with Fermi levels and their significance
  • Knowledge of quantum mechanics principles, including the exclusion principle
  • Concept of density of states and its relation to volume
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  • Research the impact of doping on semiconductor properties in silicon
  • Explore the concept of density of states in solid-state physics
  • Learn about the effects of quantum mechanics on nanoscale materials
  • Investigate the differences in band structure between macroscopic and nanoparticle solids
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Physicists, materials scientists, and engineers interested in semiconductor physics, particularly those studying the effects of doping and band structure in silicon and other solids.

ugenetic
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Look at the diagram below, after all that doping, 2 blocks of Si have the same band structure?
00906x01.png


My understanding of band structure and fermi level is that: Given a block of solid (Please note, not a TYPE of solid, but this PARTICULAR block of solid) it will have its own unique band structure and Fermi level as well. Because band structure and fermi level is the result of trillions of electrons interact with each other (obeying exclusion principle and other quantum mechanics rules) in this PARTICULAR block of solid with its particular arrangement of positive ions, lattice, imperfections, shape, mass.

The above diagram tells me that, doesn't matter if you have a block 2 billion of Si atoms or a block of 1 Billion of Si atoms or whatever kind of impurity , Valance bands will be EXACTLY the same for those 2 blocks of Si.
 
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That is not true, the density of states making up the band increases proportionally with volume.
 
DrDu said:
That is not true, the density of states making up the band increases proportionally with volume.
Thank you, that's such a relief for me here. The density of state will change, however, the height and width of a band (top edge to bottom edge) will remain the same? doesn't matter if we have 1 thousand or 1 trillion electrons? doesn't matter if the impurity's nucleus have altered the potential well/landscape/box?
upload_2015-4-1_7-45-10.png
 
These effects decrease like 1/N with increasing particle number and are therefore considered unimportant for macroscopic bodies. Only when studying nano-particles composed of only some hundred atoms, it is worth to think about corrections.
 
DrDu said:
These effects decrease like 1/N with increasing particle number and are therefore considered unimportant for macroscopic bodies. Only when studying nano-particles composed of only some hundred atoms, it is worth to think about corrections.
Thanks, so number of total electrons doesn't matter. Then what about the potential well/box change? doping atom's nucleus and electron cloud should cause... some difference right?
 

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