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Shining Light on Solar Cells - Chapter 2.0: Semiconductor Physics (Band Diagram, Free Carriers)

Welcome back to Chapter 2! Now, we are moving towards the more technical part of this video series. In order to learn solar cells, there are three prerequisites knowledge that we need to know. These are semiconductor physics, pn junction diode, and photons. These will be covered in Chapters 2, 3, 4 of the video series.

Chapter 2: Semiconductor Physics

Chapter 3: Pn Junction Diode

Chapter 4: Photons

In this chapter 2.0, we will cover the basics of semiconductor physics, starting from band diagrams and then to free carriers.

What are semiconductors?

We know our world consists of things that conduct electricity, and things that don’t. We call them conductors and insulators. Semiconductors are in between conductors and insulators. They are conductive only under certain conditions. This fundamental principle has transformed the world into the electronics world we know today. Almost all electronic devices have semiconducting components inside them!

Energy band diagrams

Energy band diagram is the most common tool used to represent and explain semiconductors, depicting the energy levels of electrons in the semiconductor.

Free carriers

Free carriers are basically freely moving electrons and holes in the conduction and valence band, respectively.

Other parts in this series:

Further reference materials that I highly recommend:

ECE Purdue Primer on Semiconductor Fundamentals 

I'm an R&D Mechanical Engineer from Keysight Technologies. I design mechanical components that facilitate over-the-air testing equipment. I also have a strong background in photovoltaics. I love creating STEM-related content to inspire and encourage people to pursue STEM, as well as to provide career advice to fresh grads who are looking for their first job