If for a particular pn junction the acceptor concentration i

If, for a particular pn junction, the acceptor concentration is 10^-16/cm^3 and the donor concentration is 10^15/cm^3, find: the junction built-in voltage (at equilibrium). Assume n_1 approximately 10^10/cm^3. the width of the depletion region (W_dep) and its extent in each of the p and n regions when the junction is reverse biased with V_R=5V. the magnitude of the charge stored on either side of the junction at this value of reverse bias. Assume the junction area is 400 meum^2.

Solution

in order to calculte the built in voltage, we have the formula,

v = kT/q *log(N(a)*N(d)/n(i))

Na and Nd is acceptor and donor concentration respectively and it is given to us :- 10^16 and 10^15 respectively. n(i) is also given to us as 10^10 we can substitute the values in equation given above.

;

In order to calculate the value of width of depeletion layer (W) we have formula:

Sqrt(2V/q(1/Na+1/Nb))