SEMICONDUCTOR ELECT : MATERIALS, DEVICES AND SIMPLE CIRCUIT
The seed of growth and development of modern solid state semiconductor electronics goes back to 1930, when it was realised that some semiconductors and their junctions have the ability of controlling the number and the direction of flow of charge carriers through them. Simple excitation with the help of light, heat or small applied voltage can change the number of mobile charge carriers in a semiconductor. The supply and flow of charge carriers in these devices are within the solid itself, no vacuum or external heating is required. So, these devices are small in size, consume low power, operate at low voltages and have long life and high reliability.
