Sheet Resistance Calculator

Work out sheet resistance instantly with clear inputs, formula shown and shareable results.

About Sheet Resistance Calculator

Sheet resistance is resistivity divided by thickness, measured in ohms per square. A conductor's resistance is then simply sheet resistance times the number of squares (length over width), which makes layout resistance estimation a matter of counting squares.

Formula

Sheet resistance

Rs = rho / t; R = Rs x (L / W)

Worked example

With the default values below, Sheet Resistance Calculator returns Sheet resistance of 0.18. Change any input above and every figure here is recalculated in your browser.

Inputs used

Material resistivity: 2.2 µΩ·cm
Film thickness: 120 nm
Conductor length: 50 µm
Conductor width: 0.5 µm

Results

Sheet resistance: 0.18 Ω/sq
Conductor resistance: 18.33 Ω
Number of squares: 100.00 squares
Current density at 1 mA: 1.67 MA/cm²

Step by step

1Values used
2Sheet resistance
3Sheet resistance= 0.18 Ω/sq
4Conductor resistance= 18.33 Ω
5Number of squares= 100.00 squares
6Current density at 1 mA= 1.67 MA/cm²

Assumptions and limits

The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

Why 'ohms per square'?

Because a square of any size has the same resistance: doubling both length and width leaves L/W unchanged. Only the aspect ratio matters.

What sheet resistances are typical?

Around 0.05-0.2 ohm/sq for thick copper metal layers, several ohms/sq for thin barrier metals, and tens to hundreds for polysilicon and diffusion.