DopingMVP
Doping → sheet resistance
Follow the chain from a doping level all the way to sheet resistance, one step at a time.
Inputs
Enter a doping level, mobility, and thickness to trace the chain.
Interpretation
Each step feeds the next: doping → carriers → conductivity → resistivity → sheet resistance.
Formula
Nd → n → σ = q·n·μₙ → ρ = 1/σ → Rs = ρ/t
n-type, educational chain.
Variables
| Symbol | Variable | Unit |
|---|---|---|
| Nd | Donor concentration | m⁻³ |
| n | Electron concentration | m⁻³ |
| σ | Conductivity | S/m |
| ρ | Resistivity | Ω·m |
| Rs | Sheet resistance | Ω/□ |
| t | Film thickness | m |
Assumptions & validity
This tool assumes:
- n-type: majority electron concentration from charge neutrality + mass action.
- Electron drift only (σ = q·n·μₙ); constant mobility; uniform film.
Worked example
Nd = 1×10¹⁸ cm⁻³, μₙ = 1400 cm²/(V·s), t = 100 nm.
n ≈ 1×10¹⁸ cm⁻³ → σ ≈ 224 S/cm → ρ ≈ 0.0045 Ω·cm → Rs ≈ 446 Ω/□