Compute junction capacitance for a p-i-n photodiode if it has area of 0.69×10 -6 m 2 , permittivity of 10.5×10 -13 Fcm -1 and width of 30μm.

Optoelectronics and Optical Communication 

Compute junction capacitance for a p-i-n photodiode if it has area of 0.69×10 -6 m 2 , permittivity of 10.5×10 -13 Fcm -1 and width of 30μm.

a) 3.043×10 -5 
b) 2.415×10 -7 
c) 4.641×10 -4 
d) 3.708×10 -5

Answer : - 2.415×10 -7

The junction capacitance is given by, 
C j = ε s A/w = 10.5×10 -13 ×0.69×10 -6 /30×10 -13 
= 2.415×10 -7 F.