Homework answers / question archive / Consider a n++183153 -p homojunction solar cell with n doping being 10/cm and p-doping being 10/cm

Consider a n++183153 -p homojunction solar cell with n doping being 10/cm and p-doping being 10/cm

Electrical Engineering

Share With

---

Consider a n++183153

-p homojunction solar cell with n doping being 10/cm and p-doping being 10/cm.

i) What is the maximum achievable open-circuit voltage (V_oc) from the solar cell. Please justify.

ii) In real life scenario, the V_oc is significantly lower than the maximum achievable V_oc. Explain with reasons. Also, suggest, what changes you need to make in the device design  for achieving V_oc closer to the maximum achievable 

iii)               Consider that the thickness of the n⁺ region (emitter) is x_n and the depletion region falls completely in the p-region. The blue light is absorbed completely in the emitter region. The total generation as a result of it is G (in s^-1cm^-2). Derive a relationship for the current density due to this generation term.

iv)               Qualitatively, plot the internal quantum efficiency curves of the above-mentioned solar cell for the following scenario

a.      The emitter has a poor lifetime with a well passivated front-surface and rear surface and high bulk lifetime of the p-region

b.     Both the n⁺ region and p-region has bulk lifetime, but the front surface is poorly passivated. The rear surface is poorly passivated.

Both the n⁺ region and p-region has bulk lifetime, but the rear surface is poorly passivated. The front surface is poorly passivated