# What does it mean for semiconductor work function to be p-type or n-type

I want to know what're n-type and p-type semiconductor work function, the difference of work function between semiconductor and metal, and how to calculate n-type and p-type semiconductor work function. Thanks a lot!

As for calculation of n-type and p-type semiconductor work function, I find some answers on the internet:

For any semiconductor, n-type, or p-type, you can calculate the work function (Φ_SEMI) using the following equation:

$$Φ_{SEMI} = χ + (E_{VBM} - E_F)$$

Where:

$$Φ_{SEMI}$$ is the work function of the semiconductor; $$χ$$ is the electron affinity of the semiconductor; $$E_{VBM}$$ is the energy of the valence band maximum; $$E_F$$ is the energy of the Fermi level.

For n-type semiconductors, the Fermi level ($$E_F$$) is closer to the conduction band minimum ($$E_{CBM}$$), so the value of ($$E_{VBM}$$ - $$E_F$$) will be negative (lower work function).

For p-type semiconductors, the Fermi level ($$E_F$$) is closer to the valence band maximum ($$E_{VBM}$$), so the value of ($$E_{VBM}$$ - $$E_F$$) will be positive (higher work function).

I think the calculation above is not right, but I confuse what's the exact answer.

$$\phi=E_{vac}-E_f$$
$$\chi=E_{vac}-E_c$$
$$\phi=\chi+E_c-E_f$$