Calculating sheet resistance

[sup17]

Homework Statement

he thickness of a copper layer, deposited to create the interconnecting tracks in an IC is 100 nm. Copper resistivity: 1.7 at 0.0039 degrees C^(-1)
What is the sheet resistance of the copper layer at 27 C?

Homework Equations

The Attempt at a Solution

I don't know what equations to use to calculate the sheet resistance. Can I get some assistance in what equation to use?

 

[berkeman]

Homework Statement

he thickness of a copper layer, deposited to create the interconnecting tracks in an IC is 100 nm. Copper resistivity: 1.7 at 0.0039 degrees C^(-1)
What is the sheet resistance of the copper layer at 27 C?

Homework Equations

The Attempt at a Solution

I don't know what equations to use to calculate the sheet resistance. Can I get some assistance in what equation to use?

Please re-post the question -- there appear to be typos in the post. Also include units for each quantity.

The basic equation for resistance is

$$R = \rho \frac{L}{A}$$

Are you familiar with that equation?

 

[phyzguy]

Sheet resistance of a film is just the resistivity divided by the thickness:

http://en.wikipedia.org/wiki/Sheet_resistance

 

[sup17]

Thanks! That really helps.

 

[rwisz]

The sheet resistance of a material can be calculated using the following equation:

R_sheet = ρ / t

Where:
R_sheet = sheet resistance (in ohms per square)
ρ = resistivity of the material (in ohm-meters)
t = thickness of the material (in meters)

In this case, the resistivity of copper at 0.0039 degrees C^(-1) is given as 1.7 ohm-meters. We can convert the thickness of the copper layer from nanometers (nm) to meters (m) by dividing by 10^9.

Therefore, the sheet resistance of the copper layer at 27 C can be calculated as:

R_sheet = (1.7 ohm-meters) / (100 nm / 10^9) = 1.7 x 10^10 ohms per square

So the sheet resistance of the copper layer at 27 C is 1.7 x 10^10 ohms per square.