doping through charged electrodes

[sweta]

Hi Quantumwise team,

how doping can be done in Au electrodes through charged electrodes using ATK 12.2.1.
What charge value I should take? For ex: charge=0.03 or-0.03 what does it mean?

[Anders Blom]

It means 0.03 more or less electrons inside the electrode unit cell. Negative values = more electrons.

[sweta]

Thanks. To add one extra electron i,e n-doping whether i should take charge=-1 or 0.01?
Is this value for per electrode per unit cell?

[kstokbro]

To add one extra electron in the unit cell use
charge = -1

[Anders Blom]

Do note however that a whole electron is usually too much, it will correspond to a doping level of 1e22/cm3 or something. Also in this case you might as well insert an actual dopant, P or B in Si for instance. So the more common use for the charge keyword is to enable a lower doping concentration without increasing the unit cell size dramatically.

[Chinha]

Hello Everyone,
I want to dope electrodes as p and n types. Built in voltage is 0.5 at zero bias. So how to do this in atk? Please help.
Thanking You.

[Anders Blom]

See http://quantumwise.com/forum/index.php?topic=2613 for an example on this feature which was introduced in ATK 13.8