I am only aware of doping into an intrinsic semiconductor. Most probably doping into a metal conductor (lets say silver/aluminium/copper): does it actually make any sense?
Just want to know. Any work of this kind?
Thanking you in anticipation
Hello Tillmann Krauss
thank you very much for your response. Alloys and doping are a bit different, am I right? As far I understand, the main difference between alloy and doping is, doping won't make any change in the lattice structure, where as alloy will form a complete new structure.
Lets say, we can get a mix of Al and Cu in nano scale with some mixing ratio and cal call that Al-Cu alloy and that's a new bimetallic nano-alloy. But what I was thinking is something a bit similar how we dope in Si and Ge. I have seen only semiconductors are doped, looking for any pure metal nanoparticle doped with another pure metal.
Thank you again for your kind response.
Doping corresponds to very small quantities of dopants added that change the bandgap width.
Alloying can have the exact ooposite effect in the lectrical conductivity .
Doping a semiconductor is vastly different from alloying.
One difference relates to the amount of the solute. Typical dopant density is 1E16 per cc. Typical alloy solute is 1% of the solution.
But a much more important difference is the geometric or non-linear effect. A micro/nano amount of the dopant can change the conductivity of the semiconductor many orders of magnitude!!
Obviously, such a non-linear (exponential or more) cannot happen in the case of conductivity. In principle, it may be possible in the case of magnetic properties.
I am not aware of any physical property change by micro/nano amount of metal B in metal A.
Thank you very much everybody for being so kind and helpful to me.
It had been very much helpful for me, all of your valuable comments. I think, with your valuable comments, now I can relate and differentiate between doping and alloying.
Once again, thank you very much for such help.
The first question would be what is the phase diagram. For ranges in the diagram where A is soluble in B, Nordheim's rule often describes the resistivity changes.
See for example slide 23 here: http://kasap13.usask.ca/ee271/files/05_conductivity-08.pdf
In low (enough) concentrations, many metals are usually soluble in metals, and this rule should provide a guidance to the general phenomena, namely, resistivity increase due to increased disorder in the lattice (and thus reduction of the electron mobility). This addition may have advantages as well, such as improved electromigration behavior as mentioned before, improved stability and more.
However, in higher concentrations or for certain other phase diagrams, different phases may form and the metallurgical aspects can be quite complex, resulting in a not-straightforward effect on the electronic properties which is hard to predict without a characterization of the microstructure.
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