What Do e and V Represent in the PN Junction Current Equation?

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What are e and V in exponent of the equation I = I0(eeV/kT - 1)? is it really one variable "eV", as in electron volts, or is e just 2.718... and V for volts?
 
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Two; e is the charge on an electron, V is the potential.
 
It's confusing. The first e is just the base of the natural logarithms (2.718...), but the e in the exponent is the charge on the electron. I prefer to write it as:
[tex]e^\frac{qV}{kT}[/tex] to eliminate this confusion. Note that if you measure kT in electron volts (eV), then the electron charges cancel, and you can just use the voltage V directly. Note that at room temperature, kT is .026 eV, so you can write:
[tex]I = I_0 e^\frac{V}{.026}[/tex]