If we dope CIGS for example. Does have the same physical meaning as we dope silicon in a simulator (like SILVACO, AMPS, PC1D, SCAPS)?
Dear Dr. Nouredine
Doping is the intentional addition of impurities to the semiconductor to control its conduction type and conductivity. In order that the introduced atoms must be in substitutional positions in the material for distinct chemical bonding lie boron and phosphorous in silicon crystals. If the material is poly crystalline and you dope it , then some of the dopant atom will be substitutional and the others may reside in the grain boundaries. This phenomenon called prepherential doping. So, polysilicon can be also doped. which means that its electrical properties can be effectively altered by doping. Amorphous Si could also be doped to produce either heavily doped p and n type layer in thin film solar cells.
Concerning the compound semiconductors., their electrical properties can be altered by doping when they are crystalline or polycrystalline.The active dopants are that which displace the regular atom in the lattice.
On the other side the properties of the compound semiconductors can be efficiently altered by mixing process. In which one uses ternary or Quaternary compounds. This process called bandgap engineering. The one uses hetero junctions instead of homo junctions. Homojunctions are formed by different doping while heterojunctions are built by different bandgap materials. Changing the mixing ratio, one gets a new material with different bandgap. This is the case of CIGS where the cupper , the indium and the gallium are divalent and occupy the same place in the lattice. Mixing can be cosidered some sort of very heavy doping.
To see the effect of mixing on the properties of CIGS solar cells please follow the link
:http://www.nrel.gov/docs/fy06osti/39773.pdf
In conclusion doping can be made but its electrical effectiveness depend on the the chemical bond of the doping atoms in the lattice of the native material.
wish you success
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