What is Doping in Physics?
Answer – In physics, doping refers to the intentional introduction of impurities into a material (especially semiconductors) to modify its properties.
Explanation:
Doping can modify a semiconductor’s electrical, optical, and structural properties. During this process, the introduction of small amounts of impurities (also called dopants) leads to an imbalance in the number of electrons present within a semiconductor. This further results in a change in properties.
Doping results into two types: n-type and p-type.
- N-type: This involves adding an impurity with five valence electrons (elements from Group 5A of the periodic table, i.e., phosphorus or arsenic) to a semiconductor with four valence electrons (silicon or germanium). This addition creates extra electrons within the semiconductor, thus making it a conductor of negative charge.
- P-type: This type of doping involves adding an impurity with three valence electrons (Group III elements from the periodic table, i.e., boron or gallium) to a semiconductor with four valence electrons (for example, silicon). This creates “holes/voids” that act as carriers of positive charge, making the material a conductor of positive charge.
Doping finds applications in devices including transistors, diodes, LEDs, and solar cells.