thin film electric resistance

[hercule]

I need help about Pt thin film or nano wire electric resistance. Because the thickness is in nanometer (~30nm), I think the resistance formula (R = p*l/s) is unusable. Please help me.

If any material about that is available, please share with me. Thanks alot

[YT2095]

do you have the Rho number for Pt?

you can`t do Squat without that

 

 

edit: take a look here, http://en.wikipedia.org/wiki/Electrical_resistivity

it has a Rho table also

[hercule]

Pt's Rho number is not my difficulty. Because Pt nano wire or thin film just has several molecules on their horizontal section, I think we have to apply modern physics here, not classical one. Is it right?

[YT2095]

it still applies, you need to work it out for a Wire the thickness of the film.

then multiply that by the width.

[swansont]

The problem here is that the bulk resistivity doesn't have the same meaning for a nanowire or thin film. There are far more interactions with the surface of the material, where the electrons might behave differently. A lot of properties of thin film or nanowire materials are different where finite size and quantum interactions are important.

 

But I can't help with the OP. Not familiar with the calculations.

[Klaynos]

it still applies, you need to work it out for a Wire the thickness of the film.

then multiply that by the width.

 

Unfortunatly not.

 

Because the film is so thin, you have to consider it as a 2d system with the electron gas. But I can't recall the formula off of the top of my head. Or even whether 60nm is thin enough, I think that this might be ok to use resistivity. I've done some resistance measurements on 50nm thick bismouth, using hall coeficients to find the resistivity. The equation used there was:

 

[math]\sigma = \frac {2lnx}{\pi t (R_{ab,cd}+R_{bc,da})}[/math]

 

Where R is the resistance between contacts on the sameple, t is the thickness, and x is the solution to a weird equation I don't seem to be able to find right now. This experiment gave me better results the thiner the sample was which implies it might be a 2D one. But the 2Dness is the key here to working out what you need.

[YT2095]

I stand corrected then, it would seem what works (and is indeed used for flat conductors) doesn`t apply at this thinness.

 

I`ll be watching this thread myself then, looks to be some neat new stuff for me to learn

[Klaynos]

A couple of my friend are doing some work on it... I can't quite remember what they're investigating though, I know an offshot is the quantum hall effect....

 

If I get a chance I'll have a look for some papers on it later...

[YT2095]

cool, the only thing I`m partly familiar with as an application is Solar Panel technology.

[hercule]

My Pt nanowire is 30 nm thick x 50 nm wide x 70 um long. That means the thickness has 80 molecules. There are many documents about semiconductor nanowire (in FET - field effect transistor ) but Pt is not a semiconductor.

 

And I think that 80 molecules thick nanowire is not suitable for the theory of quantized (quantum) conductance, for instance the theory of Persson about the conductance change per adsorbate molecule :

 

G: conductance

d: thickness

F: width of r(e) ( the density of states of the adsorbed molecules at the Fermi energy of the metal)

 

What formula can I apply for my Pt nanowire?