To determine the density of donor ions (ND) at the P-N junction, we use the formula for the barrier potential (V0) of a P-N junction:

To determine the density of donor ions ($N_D$) at the P-N junction, we use the formula for the barrier potential ($V_0$) of a P-N junction:

$$V_0 = V_T \ln\left(\frac{N_A N_D}{n_i^2}\right)$$

where $V_T$ is the thermal voltage, $N_A$ is the acceptor concentration, and $n_i$ is the intrinsic carrier concentration.

Step 1: Calculate the thermal voltage ($V_T$).
The thermal voltage is given by $V_T = \frac{kT}{q}$.
Given:

• Temperature, $