Before the discovery of transistor, devices such as vacuum diode were used to control the flow of electrons in a circuit. But these devices were bulky, consumed high power, operated at high voltages and had limited life and low reliability. In the 1930’s it was realised that come solid state semiconductors and their junction offered the possibility of controlling the flow of charge carriers through them. This led to the development of the modern solid-state semiconductors. They consume low power, are small in size, operate at low voltages and have a long life and high reliability. In this chapter, we study the following concepts:
- Basic concepts of semiconductor physics
- Semiconductor devices such as bipolar junction transistor and junction diodes.
- Applications of semiconductors
Frequently asked Questions on CBSE Class 12 Physics Notes Chapter 14: Semiconductor Electronics
Who discovered the transistor?
John Bardeen, Walter Brattain and William Shockley invented the first working transistors at Bell Labs, the point-contact transistor in 1947.
What are ‘Semiconductors’?
Semiconductors are substances with properties somewhere between them. ICs(integrated circuits) and electronic discrete components such as diodes and transistors are made of semiconductors.
What is a ‘Bipolar junction’?
A Bipolar Junction Transistor is a solid-state device in which the current flow between two terminals (collector and emitter) is controlled by the amount of current that flows through a third terminal (base).