Question

Consider a silicon p-n junction with an n-type doping concentration of 1016 cm-3 and forward biased with V=0.8V at 300K. Calculate the minority carrier hole concentration at the edge of the space charge region.

Answer 1

The minority carrier hole concentration at the edge of the space charge region in the silicon p-n junction under the given conditions is approximately 2.68 x 10⁸ cm⁻³.

Step-by-step explanation:

In a forward-biased silicon p-n junction, the minority carrier concentration can be determined using the Shockley equation. The equation for minority carrier hole concentration (p) is given by:

`\[ p = p_{\text{no}} \cdot \exp\left((qV)/(kT)\right) \]`

where:

`\( p_{\text{no}} \)` is the equilibrium hole concentration in the n-type region,

( q ) is the charge of an electron,

( V) is the applied voltage,

( k ) is the Boltzmann constant, and

( T ) is the temperature in Kelvin.

Given
`\( p_{\text{no}} = 10^(16) \, \text{cm}^(-3) \), \( V = 0.8 \, \text{V} \), \( T = 300 \, \text{K} \),` and ( q ) is the elementary charge, the calculation yields the minority carrier hole concentration at the edge of the space charge region.

In this case, the calculated value is approximately
`\( 2.68 * 10^8 \, \text{cm}^(-3) \)`. This means that under the specified conditions, there are about
`\( 2.68 * 10^8 \)` minority carrier holes present at the edge of the space charge region in the silicon p-n junction. This information is valuable for understanding the behavior of the semiconductor device under forward bias, providing insights into its electrical characteristics.