Is the activation process the main responsible for Band gap in semiconductors?
(especially carbon nanostructures; the quantum confinement is the source of band gap creation in nanostructured semiconductors, but what about the other factors)
Quantum confinement is prominent in naomaterials. As the nanoparticle size decreases bendgap incraeses. But, what I understood, band gap is inherent in material which can be changed by doping and temperature variation.
Thanks.
But the question is , what are the other effective parameters in bad gap creation of typical semiconductor? (except quantum confinement, doping, temperature)
What about indirect parameter like activation energy?
In typical semiconductor, Which parameters effect on Eg?
In other words, generally we use R-T measurement for band gap extraction, what if it was a carbon heterostructure on nanocoposite semiconductor?
Can we say it is a working method (R-T) for all kind of semiconductor material?I am not sure if it works for that complicated carbon structure. Because I am not sure about the source of creation of band gap for those material.
What happen for band gap if several conduction mechanism get involve in transport?
I can answer the third question: in typical semicon as Si, band gap changes by changing material composition, for a basic example, as in the case of amorphous dielectrics, band gap changes by diverse factors: taking the case of PECVD formation of semicon materials, activation energy as RF or MW change chemical composition of gas cloud and therefore bandgap of material may be affected; if you change the rate of precursor gas to carrier gas, bandgap changes; even the temperature of substrate affects the bandgap
Thanks Elias. I suppose you mean thickness variation changes the band gap which is true. In terms of activation energy, I mean the activation energy of material like silicon. RF energy is the required for chemical composition as you mentioned which is different from material activation energy Ea = Eg/2.
Sorry, I would like to help, but I don't understand what you mean by "material activation energy Ea = Eg/2" – activation of what? Please explain this in more detail.
Further, I don't know what you mean by "R-T measurement"; could you please explain this abbreviation?
Additionally, I don't understand your remark: "What happen for band gap if several conduction mechanism get involve in transport?" Generally speaking: Why should a conduction mechanism influence the band gap? In reality, it is the other way round: For a crystalline material the conduction type (isolator / semiconductor / metal) depends crucially on the magnitude of the band gap.
In general, the magnitude of the band gap depends crucially on the lattice constant. For silicon, this is nicely illustrated in the following image: http://www.tf.uni-kiel.de/matwis/amat/mw_for_et/kap_8/illustr/si_band_entstehung.gif (where "Leitungsband" means "conduction band", "Lücke" means "band gap", and "Valenzband" means "valence band").
When various atoms join together various atomic orbitals are bunched having various energy levels to form molecule/compound.
- Badges
- Science topic
- Similar topics
- Chemistry
- Nanotechnology
- Nanostructures