How Semiconductor Works

A Semiconductor can be defined as a material that has the characteristics and ability to conduct a small amount of electrical current. Semiconductors have much lower resistance to the flow of electrical current in one direction than in another. Electronic Components such as Diodes, transistors, and many photovoltaic cells contain semiconductive materials. The electrical conductivity of a semiconductor device can be controlled over a wide range, either permanently or dynamically.

Which Materials are used to make a Semiconductor?

There are several materials that are used to make a semiconductor. The basic requirement of a semiconductor is that it should not be a very good conductor of electricity, nor should it be a very bad conductor of electricity. Its properties can be changed by adding or removing atoms. Silicon is the most widely used semiconductor material. Few other materials used in making semiconductor are germanium, gallium arsenide, and silicon carbide.

How are Semiconductors Made?

Manufacturing semiconductors need expertise and experience. Chemicals to be used need to be pure and free from any impurity. The process of adding controlled impurities to a semiconductor is known as doping. Silicon wafers are an important ingredient in manufacturing semiconductors.

Semiconductor Manufacturing Process:

  1. Design / Mask Creation: During this phase, the function of the semiconductor / IC is defined, the electric circuit is designed, and a mask for IC manufacturing is created based on the design.
  2. Patterning: This procedure is used for the formation of a circuit pattern during various front-end processes.
  3. Wafer Fabrication: During this phase, an IC is created on a silicon substrate (wafer).
  4. Device Formation / Device Insulation Layer Formation: A device insulation layer (field oxide-film) is formed for electrical isolation of the devices.
  5. Device Formation / Transistor Formation: Transistors are formed in the active regions to control the flow of electrons.
  6. Metallization: Devices, such as transistors, are interconnected to form an electronic circuit.
  7. Assembly and Testing: During this phase, the IC chips created during the wafer fabrication phase are encapsulated into packages, and thoroughly inspected before becoming completed products.

How Semiconductor Works

How Semiconductor Works

How Semiconductor Works

All semiconductor materials like silicon, germanium, gallium arsenide, and silicon carbide have a unique property – All of them have 4 electrons in their outermost orbit. All the 4 electrons form perfect covalent bonds with four other atoms creating a lattice to form crystals. These crystals may look like a diamond (if the semiconductor material used is carbon) or it may look like a silver metallic substance (if the semiconductor material used is silicon).

Most semiconductors are made by using silicon since it is abundantly available on earth and is easy to work with. When an “impure” substance, such as boron or gallium is introduced in small quantity, it causes the silicon crystal to become unstable. This instability allows free movement of electrons. Free movement of electrons causes an imbalance of electrons. This imbalance of electrons can generate a charge which can be either a positive charge (if there are lesser electrons) or a negative charge (if there are more electrons).

Conclusion

Silicon is the most widely used semiconductor material. Electrons are negatively charged and protons are positively charged while neutron has no charge. Semiconductors works due to imbalance of electrons that carry negative charge. This imbalance of electrons generates positive (where there are excess protons) and negative charges (where there are excess electrons) at two ends of surfaces of the semiconductor material. This is how a semiconductor works.

Related Posts:

Leave a Reply