SLIDE 1
Arno Smets
Semiconductor Junction
p region
- Hole
Working Principle of a Semiconductor Based Solar Cell Semiconductor - - PowerPoint PPT Presentation
Working Principle of a Semiconductor Based Solar Cell Semiconductor - - PowerPoint PPT Presentation
Working Principle of a Semiconductor Based Solar Cell Semiconductor Junction I - Basic Principles Week 2.4.1 Arno Smets Semiconductor Junction Band Band Hole Electron diagram diagram - - - - + + + + - - - - + + + + - -
SLIDE 2
SLIDE 3
Semiconductor Junction
n region p region
- +
+ + + + + + + + + + + + + + + + + + +
SLIDE 4
Semiconductor Junction
n region p region
- +
+ + + + + + + + + + + + + + + + + + +
SLIDE 5
Semiconductor Junction
n region p region
- Negatively Charged Positively Charged
+ + + + + + + + + + + + + + + + + + + +
Electric field
SLIDE 6
Semiconductor Junction
- +
+ + + + + + + + + + + + + + + + + + +
n region p region Diffusion of holes and electrons close to the junction
SLIDE 7
Semiconductor Junction
- +
+ + + + + + + + + + + + + + + + + + +
Space Charge region n region p region
- +
E-Field
SLIDE 8
No net current
Semiconductor Junction – Thermal Equilibrium
- +
+ + + + + + + + + + + + + + + + + + +
n region p region
Electron Diffusion Je= qDedn/dx
SLIDE 9
No net current
Electron Drift Je = nqeE
Semiconductor Junction – Thermal Equilibrium
- +
+ + + + + + + + + + + + + + + + + + +
n region p region
SLIDE 10
No net current
Hole Diffusion Jh = qDhdp/dx
Semiconductor Junction – Thermal Equilibrium
- +
+ + + + + + + + + + + + + + + + + + +
n region p region
SLIDE 11
No net current
Hole Drift Jh = pq hE
Semiconductor Junction – Thermal Equilibrium
- +
+ + + + + + + + + + + + + + + + + + +
n region p region
SLIDE 12
Semiconductor Junction – Thermal Equilibrium
Potential energy of water level ~ Fermi level
SLIDE 13
Semiconductor Junction – Band diagram
p-type
EF
n-type
EF
SLIDE 14
Semiconductor Junction – Band diagram
n-type p-type
EF EF
SLIDE 15
Semiconductor Junction – Band diagram
n-type p-type
EF EF
SLIDE 16
Semiconductor Junction – Band diagram
n-type p-type
EF EF
SLIDE 17
Semiconductor Junction – Band diagram
n-type p-type
EF EF
SLIDE 18
Semiconductor Junction – Band diagram
n-type p-type
EF EF
SLIDE 19
Semiconductor Junction – Band diagram
n-type p-type
EF EF
qVbi
SLIDE 20
Semiconductor Junction – Band diagram
EF EF
drift diffusion drift diffusion
SLIDE 21