Question

A semiconductor is known to have an electron concentration of 5×10¹² cm⁻³ and a hole concentration 8×10¹³ cm⁻³ Is the semi-conductor n-type or p-type? What is the resistivity of the sample, if the electron mobility is 23,000 cm² V⁻¹s⁻¹?

Answer 1

The semiconductor with higher hole concentration is a p-type semiconductor. Resistivity calculation requires electron and hole mobilities along with their concentrations, but we only have electron mobility and concentrations provided.

Step-by-step explanation:

Given the electron concentration of 5×10¹² cm⁻³ and a hole concentration of 8×10¹³ cm⁻³ in a semiconductor, we can determine the type of the semiconductor by comparing these concentrations. The higher concentration of holes suggests that this is a p-type semiconductor, where the majority carriers are holes.

To calculate the resistivity of the semiconductor, we use the formula ρ = 1 / (μₙnₙ + μᵥpᵥ), but we lack the hole mobility (μᵥ) and electron concentration (nₙ). However, knowing the electron mobility (μₙ) of 23,000 cm² V⁻¹s⁻¹, we can infer that if both the electron and hole mobilities were known, along with their concentrations, we could calculate the resistivity.