A solid chemical element that has the ability to conduct electric current through it under certain conditions is called a semiconductor. In other words, it can be said that a semiconductor is a substance that lies between a conductor and an insulator. The amount of current that flows through a semiconductor depends greatly on the amount of current or voltage supplied to it. Devices such as telephones, radios, computers, etc are made using semiconductor materials.
The two main types of semiconductors include an N-type semiconductor and a P-type semiconductor.
Silicon is the most commonly used element for making semiconductors. However, some other materials used for making semiconductor include germanium, silicon, selenium, boron, and carbon etc.
Semiconductors are also commonly referred to as Integrated Circuits (ICs). These ICs are able to allow a large number of electrical circuits which are further connected to transistors and other electrical devices. A Pure semiconductor is known as intrinsic semiconductor. The ability of a semiconductor to conduct can be changed by adding any form of impurity into the intrinsic semiconductor. This is usually done by first melting the intrinsic semiconductor and then adding the impurity in the melted form in it. The melted material in then allowed to cool down and form a new crystal. This process is known as doping.
Today, Semiconductor manufactures use silicon chips. Silicon is actually a naturally occurring semiconductor and is capable of conducting electricity and can act as an insulator as well. As silicon is a readily available substance, Semiconductors manufactured using silicon are usually low in cost and high in efficiency. The process of manufacturing semiconductors or ICs usually involves six basic steps for wafer processing. After the wafer processing has been done, each chip is then tested and analyzed for electrical capability. After this, the ICs are cut accordingly and sent for packaging. They are again tested for their electrical performances before being sent out to the distributors into the market.
In the manufacturing of semiconductors, the amount of chemical purity needs to be strictly checked because even a smallest form of an undesirable impurity can have an affect of the performance of the semiconductor. Furthermore, any defect in the crystalline structure such as dislocations, twins, or stacking faults can also result in malfunctioning of the semiconductor material. Usually crystalline ingots ranging between 100 mm to 300 mm in diameter are used in the making of semiconductors which are later on sliced into wafers accordingly.
So, all in all, a certain level of chemical purity and accurate crystalline structure is highly important for the manufacturing of the perfect semiconductor. Usually, the semiconductor manufacturing companies make use of the Czochralski process and Zone refining process in order to achieve maximum purity in the construction of the ICs.
The impurities are made to leave behind by melting a part of solid in the zone refining process. In this way, the material left behind consists of lesser number of crystalline faults. Lattice constant measures the length of the recurring elements of the crystalline structure of the semiconductor material. This lattice constant is highly significant in determining the compatibility and effectiveness of the semiconductor devices during the course of manufacturing which involve and concern heterojunctions between diverse semiconductor substances.
