$$R=\frac{\rho L}{A}$$
- $R$ = Resistance
- $\rho$ = Resistivity ($\Omega cm$)
- $L$ = Length
- $A$ = CS Area

$$J=\sigma E$$
- $J$ = Current Density
- $\sigma$ = Conductivity ($\frac{1}{\Omega cm}$)
- $E$ = Electric Field

$$V_{bi} = \frac{kT}{q}ln(\frac{N_D N_A}{n_i^2})$$
- $V_{bi}$ = Built-in Potential
[[Doping]]
$$J=nev$$
- $n$ = Charge Density
- $e$ = Charge
- $v$ = Drift Velocity

$$v=\mu E$$
- $v$ = Drift Velocity
- $\mu$ = Mobility
- $E$ = Electric Field

$$\sigma = ne\mu$$
$$\rho=\frac{1}{\sigma}$$
$$\sigma=q(\mu_nn+\mu_pp)$$
- $q$ = Electronic Charge
- $\mu$ = Carrier Mobility ($\frac{cm^2}{Vs}$)
$$1 eV = 1.602\times 10^{-19}J$$