2. Answer the following questions based on the information below about Semiconductor X

- Semiconductor X has a total of four valence electrons.

- The band gap of the semiconductor X is 2.6 eV.

- The electron density of the undoped semiconductor X (i.e., intrinsic electron concentration) is 10^8 carriers/cm^3 at room temperature (T=300K).

- The doped semiconductor X reaches intrinsic regime at a temperature of 500K or higher.

- A single crystal substrate (wafer) made of semiconductor X was doped at a concentration of 10^9 dopants/cm^2 using an atom Y with a valence electron number of 2.

- A single crystal substrate (wafer) B made of semiconductor X was doped at a concentration of 10^16 dopants/cm^3 using an atom Z with a valence electron number of 6.

- The ionization energy of dopant Y and Z is 10 meV and 15 meV, respectively.

- The thermal energy at room temperature is KT=26meV.

A. Which semiconductor is n-type doped, substrate A and substrate B?

B. Find the free electron density and hole density on substrate A and substrate B at room temperature.

C. Graph the correlation between the concentration (n) and the temperature of electrons in substrate A and substrate B. (where x-axis is 1/T and y-axis is log(n)). Specify the concentration of electrons on the y-axis when 1/T=1/300K. Draw the electron concentration of substrate A as a solid line and the concentration of substrate B as a dotted line.

D. Find the free electron density and hole density of substrate A and substrate B at 1000K.

E. Draw the following correlations for a given p-type substrate between substrate A and substrate B by comparing them under conditions of 300 K (solid line) and 1000 K (dotted line), respectively. Indicate the conduction band and the valence band. Y-axis vs. x-axis

- Energy vs. occlusion probability (f): Make sure to indicate the location of the fermi level under both conditions

- Energy vs. Density of states (DOS): Assume that the effective mass of electrons and holes is the same

- Energy vs. Carrier distribution: Draw the energy distribution of electrons in the conduction band and the energy distribution of holes in the valence band

F. Graph the correlation between the electron of substrate A and the charge mobility of substrate B and the temperature of substrate B with the x-axis as 1/(temperature) y-axis as log mobility. However, draw the relationship of substrate A as a solid line and the relationship of substrate B as a dotted line.

G. Explain why there is a difference if there is a difference between the two graphs, and why there is no difference if there is no difference, in relation to the charge transfer mechanism of the semiconductor.