What temperature does p-Ge translates from extrinsic to intrinsic ?

[bushel]

Hi,

I have expermentally measured the resistivity, Hall mobility concentration of a p-type germanium sample at the range of 300K-700K. The task I want to accomplish is, given the fact that I know NA= 4.5E17 and acceptor is boron.

- How can I calculate the expected transition temperature from extrinsic to intrinsic?
- How can I assume the expected resistivity, mobility and concentration values so I can compare them with the experimental values? Which scattering mechanisms will dominate?

Thanks in advance.

 

[BigJDubs]

The transition temperature from extrinsic to intrinsic conductivity is typically taken as the temperature at which the mobility and concentration of the majority carriers reach their maximum values. To calculate the expected transition temperature, you can use the following equation: Tt = (2*k*NA) / (ln(mu_max * n_max)) where k is the Boltzmann constant, NA is the acceptor concentration, mu_max is the maximum mobility, and n_max is the maximum concentration. To calculate the expected resistivity, mobility, and concentration values, you will need to consider the scattering mechanisms that are expected to dominate in the sample. For p-type germanium at temperatures between 300K and 700K, the dominant scattering mechanisms are likely to be ionized impurity scattering, acoustic phonon scattering, and piezoelectric scattering. You can then use a drift-diffusion model to calculate the expected resistivity, mobility, and concentration values for these scattering mechanisms.