In PN junction diode, P side is doped with acceptor concentration of 2 × 1016 cm-3, N side is doped donor concentration of 5 × 1017 cm-3. The contact potential of diode is:
Assume thermal equivalent voltage equal to 26 mV and intrinsic carrier concentration equal to 1.45 × 1010 cm-3.
A. 0.82 V
B. 0.2 V
C. 1.2 V
D. 0 V
Answer: Option A
This Question Belongs to Electronics And Communications Engineering >> Electronic Devices And Circuits
Formula:
Vbi = Vt ln (NA.ND/ni^2)
where
Vt = KTq = 26 mv = 0.026 v
NA = 2 * 10^16
ND = 5 * 10^17
ni = 1.45 * 10^10
Vbi =( 0.026 ln 1 * 10^34) / (2.1025 * 10^20)
= 0.82 v