The Importance of Transistors in Integrated Circuits (ICs)

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An integrated circuit is an electronic component whose main body is made of semiconductor material. The name ‘integrated’ is mainly because it comprises of different small electronic components that have been brought together to function as a unit. These components include many transistors among other vital components such as capacitors, resistors, diodes, and many others.

All electronic devices depend on the integrated circuits to run. Also, a single device is likely to have multiple integrated circuits whereby each IC takes care of a particular functionality in the device.

Take an example of a computer, it has a power unit, processing unit, memory unit, network unit, interface, or external connections among other functionalities. There is a special integrated circuit that is designed to take care of each of these problems.

In this article, our attention is on the transistors. We are going to look are what it does and the roles that it plays in the integrated circuits.

Table of Contents

What is a transistor?

A transistor is an electronic component that is designed to amplify and switch electric signals. Made of high-grade semiconductor materials, transistors are prevalent in most electronic applications, including in integrated circuits.

Not all transistors are the same. They come in different types based on the way that they have been manufactured and configured. The two main types are Field-effect transistors (FET) and Bipolar junction transistors (BJT).

The main difference between these two types of transistors is the number of the PN junctions that they have. BJT transistors have two PN junctions while FET have one PN junction. Furthermore, two of the three regions in the BJT transistors have the P-type semiconductor material and one region has the N-type. This implies that it takes the PNP transistor configuration. The n-type region is the base and is the controlling terminal. The other two regions are the source and the emitter.

On the other hand, FET transistors are referred to as unipolar transistors mainly because they have two regions. The n-type and p-type regions. The working mechanisms of these transistor types is single carriers meaning that only one type of charge carriers can be used at ago but not both. FETs come in different variants and the most popular one is the MOSFET.

Functions of transistors in integrated circuits

Here are the main functions of transistors in an integrated circuit:

They are used as switches

Switching is among the top functions of transistors in integrated circuits. With this function, it means that a transistor can determine the flow of electric current in an integrated circuit. It determines whether the whole IC or components in the IC should be in an ON state or OFF state.

The fact that the operation of all the electrical applications are defined by these two states underlines the relevance of transistors in integrated circuits.

Analyze the operation of the logic circuits and you will recognize that the entire logical operation is based on the On and Off states which stand for the binary numbers. The same concept is used on the digital circuits.

Amplification

This is another primary role of transistors in integrated circuits. They are used for amplifying electric signals or currents. Amplification is necessary when the signals getting into an electric circuit are weak and yet they are needed to run powerful loads. It will be necessary for these signals or currents to be amplified to the levels in which they can run the loads; this is where the importance of the transistors comes in.

By raising the amplitudes of the transistor also increases the frequency of the electric signals hence amplifying them.

For memory purpose

Transistors in integrated circuits can also serve as memory devices. This usually happens when transistors are used with other electronic components such as capacitors. For example, the dynamic random access memory (DRAM) in integrated circuits comprises of transistors that work in tandem with the capacitors to provide short-term memory service. Here, data is stored in the form of electric charges.

Power regulation in integrated circuits

Power transistors are used in integrated circuits to perform the role of voltage regulation. The configuration of these transistors ensures that the current supply in the integrated circuits remains stable at all times. This helps to protect sensitive devices from the effects of high voltage. It also minimizes the possibility of power surge.

How to add transistors into integrated circuits

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Since transistors are independent electronic components, how are they added to integrated circuits?

Embedding transistors into ICs usually takes place during the fabrication of the integrated circuits. This is the stage where all the essential electronic components are added to the semiconductor wafer. Those are the components that will end up giving the microchip its functionality.

There are several steps and procedures that take place during IC fabrication, a process that included embedding transistors onto the semiconductor. The first step entails designing the microchip. Here, the IC manufacturer creates a picture of what is intended to be the final product.

From the design phase, high-tech procedures are executed on the semiconductor. They include the preparation substrate, oxidation, photolithography, etching, and finally packaging. The advancement of technology has made it easier to execute all these steps within a short time

Conclusion

It is impossible to underestimate or even ignore the importance of transistors in integrated circuits. With all the functions that we have discussed above, it is pretty obvious that an IC will not be functional without the transistors. This explains why most integrated circuits have many transistors.

So, are you working on an electronic project which will have a microchip? You will have to consider including transistors in your plans. Not just any transistor but should be of the right type and perfect quality. This is why you should carefully consider where you buy transistors. Choosing a reputable and reliable transistor supplier will ensure that you execute your project perfectly. Once you have decided on the type of transistors that are suitable for your project, the next step will be to contact the supplier and place your order.