P-Type Semiconductors – revision notes

P-type semiconductors are obtained by adding trivalent impurities (Boron, Gallium, Indium, Aluminum) to a pure semiconductor. The three valence electrons of the impurity atom form covalent bonds with neighboring semiconductor atoms and the fourth covalent bond has a vacancy. This gives rise to a hole in the semiconductor. Thus the addition of trivalent impurity atom […]

N-Type Semiconductors – revision notes

N-type semiconductors are obtained by adding pentavalent impurities (Bismuth, Antimony, Arsenic, and Phosphorous) to a pure semiconductor. The four valence electrons of the impurity atom form covalent bonds with four neighboring semiconductor atoms and the filth electron is free to move in the crystal. Thus the addition of pentavalent impurity atom provides free electrons to […]

Properties of P-type and N-type material & their differences

let us go through the properties of P-type and N-type semiconductors. Then we will compare P-type and N-type semiconductors, as well. P-type and N-type material In Figure 1, the left side material is a P-type semiconductor having negative acceptor ions and positively charged holes. The right side material is an N-type semiconductor having positive donor […]

Types of semiconductors – intrinsic (pure) and extrinsic (impure)

Semiconductors may be classified into 2 types: (1) Intrinsic (pure) semiconductors, and (2) Extrinsic (impure) semiconductors. In this post, we will learn more about intrinsic (pure) semiconductors, the Movement of Holes in Intrinsic or pure Semiconductors, Extrinsic (impure) semiconductors, and the purpose of adding impurity. Intrinsic (pure) semiconductors Semiconductor in its extremely pure form is […]

Commonly used semiconductors: Germanium & Silicon

There are many semiconductors available, but very few of them have practical applications in electronics. The two commonly used materials are Germanium (Ge) and Silicon(Si). In Ge and Si, the energy required to break the covalent bond (energy required to release an electron) is very small. For Ge, it is 0.7 eV and for Si, […]

Energy Bands in Solids – types of bands, & forbidden energy gap

In an isolated atom, the energy levels of electrons in various orbits can be represented by horizontal lines. Such a diagram is called Energy Level Diagram. Atoms of gases can be considered isolated because of their greater spacing under normal pressure and temperature. Hence the energy levels of such atoms are not affected by other […]

Doping of semiconductors – revision notes

Doping is the process of adding impurity atoms to an intrinsic semiconductor material or semiconductor. Here, in this post, we will discuss the doping process in detail. semiconductors Germanium and silicon are examples of semiconductors. Silicon and germanium have a unique property in their electron structure. Each of these elements has four electrons in its […]

Light-dependent resistors (LDR) – fundamentals

A light-dependent resistor (LDR) is a semiconductor component with a resistance that depends on the intensity of the light that is incident on it. The greater the intensity, the lower the resistance of the LDR. How LDR works Light provides the energy to release charge carriers and decrease the resistivity of the material. Higher intensity […]

Scroll to top