What Is Silicon?

Silicon (Si), one of the chemical elements in the periodic table, refers to its atomic number, 14 - the number of protons found in an atom's nucleus.

Silicon makes up an estimated 28.3% of Earth's crust by mass and exists in several forms or allotropes, but silica (silicon dioxide) is the most common.

It has physical properties that are intermediate between carbon and germanium, which makes it useful as a semiconductor.

It is also known as the "quintessential nonmetal" because it has similar properties to metals in some ways but not all.

Properties of Silicon

A crystalline solid, silicon has a blue-gray metallic luster. While silicon does not have the same properties as its fellow group 14 elements, germanium and tin, which are metalloids, it is considered a metalloid like them.

Silicon has four valence electrons and reacts readily, forming compounds with most other elements (usually covalent bonds), primarily its lighter congeners carbon and germanium, heavier ones like lead and tin, and the chalcogens oxygen, sulfur, and selenium.

Physical Properties

The physical properties of silicon include:


Chemical Properties of Silicon

The chemical properties of silicon include:


History of Silicon

The discovery of silicon is attributed to the Swedish chemist Jons Jacob Berzelius who, in 1824, isolated a white material from the mineral "spar" from a quarry in Utö, Sweden.

In 1854, Charles Friedel and James Crafts isolated elemental silicon by reducing sodium fluoride with potassium metal.

Silicon was first produced commercially in 1895 by the German firm H. Merck & Company. The process involved a carbothermal reduction of silica with coke or anthracite in a furnace.

The silicon was then melted into an ingot, extracted by hydrogen reduction to leave a nearly pure metal. Before World War II, almost all commercial silicon was produced from low-grade metallurgical slag containing 30% SiO2 x H2O.

The n-type semiconductor is an intrinsic semiconductor in which the majority carrier has an excess of electrons (the electron donor). This type of silicon makes solar cells.

To make p-type semiconductors, either intrinsic or pure, doped material can be used. Heavily doped material is required for the p-type material so it can offer sufficient conductivity.

Usage of Silicon

Silicon is used in many ways. A few specific usages include:

  • It serves as the basis for most integrated circuits (ICs). Nearly every electronic device today contains silicon ICs, found in practically every device with electric circuits

  • It is used in transistors, solar cells, light-emitting diodes (LEDs), and other semiconductor devices. Small quantities of germanium can be alloyed with silicon to produce better transistors that withstand higher temperatures

  • Silicon carbide is utilized as an abrasive in the manufacturing of ultrahard materials. It is also used as a semiconductor material in power electronics

  • It is alloyed with metals to make high-performance alloys for use in high-temperature environments or reduce the metal's weight

Advantages and Disadvantages of Silicon as a Semiconductor

The advantages and disadvantages of silicon as a semiconductor include:


  • It is easy to produce in large quantities and can achieve low prices for the end product

  • It can create covalent bonds with other atoms, such as hydrogen and nitrogen, because it has four valence electrons

  • The bandgap is 1.1 eV, which means that it has the potential to conduct electricity under the right conditions

  • It works well with semiconductors to create integrated circuits. This means computers and other electronic devices can be designed from silicon.


  • In its pure form, it is neither a good conductor nor an insulator, making it hard to use as an electrical material without alloying it with other materials

  • It has a high melting point, meaning it requires more energy to melt than many other semiconductors. It can change the manufacturing process and increase costs for silicon-based semiconductors

  • It can break down at very high temperatures. This means that it is only useful as a semiconductor up to a specific temperature, limiting its applications

The Bottom Line

Silicon, which makes up an estimated 28.3% of Earth's crust, is the second most abundant element on Earth. It is a chemical element and useful as a semiconductor due to its similarity to carbon.

It is widely used in semiconductor devices like transistors and solar cells. It is known as an element with metalloid properties and has four valence electrons.

Silicon can be alloyed to produce high-quality transistors and solar cells, and it forms the basis for most modern integrated circuits.

Additionally, silicon carbide is used as an abrasive in manufacturing ultrahard materials. Silicon dioxide is used for different purposes, such as etching, glass blowing, paint filler, concrete fiber, fiberglass insulation, and baking soda (sodium bicarbonate).


1. What is the atomic number for silicon?

Silicon has an atomic number of 14 and a relative atomic mass of 28.085 u.

2. Is silicon a unique element?

Silicon is a semiconductor widely used in electronics and other industries. It tends to bond readily with other carbon-based elements. Silicon can be alloyed with other metals to create lightweight metals in high-heat, high-pressure environments.

3. How is silicon used?

Silicon is highly abundant and has many uses. It is primarily used in the semiconductor industry and has other practical applications where it is alloyed with other elements.

4. Where can you find silicon?

Silicon comes from the Earth's crust and atmosphere. It is mined on land and overseas in China, Germany, South Africa, and the United States.

5. Is silicon a metal, nonmetal, or metalloid?

Silicon is a semiconductor and not metal. It does not form any positive ions in the ground state and has low electrical conductivity in its pure form.

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