The Application of FinFET Technology in the Manufacture of Semiconductors Term Paper

Introduction

The degree of electrical conductivity of semiconductors is between that of metal and an insulator. Such materials form the foundation of modern electronic device production. What this means is that they are used in the manufacture of a wide range of electrical devices. The devices range from transistors and diodes to integrated circuits.¹

Semiconductor materials have a unique characteristic that makes them indispensable in the manufacture of electrical devices. For example, the materials have the ability to change their level of conductivity with the addition of impurities. There is a specific technique used in the addition of these impurities. The technique is referred to as doping.² There are a number of techniques used in the production of semiconductors. The techniques include the application of ‘interacting’ phenomena, such as electrical fields or light. Gating techniques are also used in the production of semiconductors. The property of these materials makes it possible to use semiconductors in the development of devices used for a number of electrical purposes. Such purposes include switching, amplifying, and converting energy input from one form to another.

Semiconductor materials are produced with the help of a wide range of technological innovations. In this paper, the author seeks to discuss FinFET technology, one of the scientific techniques that are widely used in the production of semiconductors. The technique is used to produce semiconductors through gating.

Application of FinFET Technology in the Production of Semiconductor Materials

The term FinFET was initially used to refer to a double-gate, non-planar transistor. Initially, the transistor was built with ‘silicon on insulator substrate’. Transistors produced through FinFET technology are similar to their predecessors, the single gate transistor models. The latter is often referred to as the DELTA design.

There is one major difference between the two transistors. The conducting channels of FinFET transistors are wrapped with thin ‘fins’. The fins form the body of the device.³ Today, the term FinFET is used generically to refer to any transistor that is multigate in nature. Such a transistor is characterized by a fin-based architectural design regardless of the number of gates that it contains. The thickness of the silicon fins that are used is very significant. It acts as a major determinant of the effectiveness of the device’s channel length. There is a formula used to measure the thickness of the fin in the transistors. It is computed as the distance between the source and the drain.

With the use of FinFET technology, many designs of semiconductor materials can be produced. In 2002, the Omega FinFET design was launched by a company based in Taiwan, which specializes in the manufacture of semiconductors. The name ‘Omega’ came as a result of the design’s resemblance to Omega, the Greek letter symbolized by Ω. The shape of the source and the drain structures, when they are covered by the gate, resembles the Greek letter. The development of the design was seen as a breakthrough in the manufacture of transistors for a number of reasons. For starters, the Omega FinFET transistors require low voltage compared to the traditional single-gate transistors.⁴ The transistor, for instance, only requires 0.7 volts to function.

In the recent past, power consumption has emerged as one of the major problems affecting the production of transistors. To this end, manufacturers strive to produce transistors that consume less power. As a result, the cost of maintaining the devices made using these resistors may be reduced.³ The reduction in power consumption not only reduces the cost of power used, but also helps deal with thermo issues associated with semiconductors. The use of more power in semiconductors would translate to the production of more heat as a result of resistance to current flow. By using less power, FinFET technology addresses the issue of thermo heating.

There is another advantage associated with Omega FinFET transistors. The advantage is noted in the gate delay associated with the transistors produced using this technology.⁴ For example, the delay is significantly reduced for the n-type design. The technology brings down the delay to about 0.39 picoseconds for this design. It is reduced to 0.88 picoseconds for the p-type. Such delays are much lower compared to those in transistors made using other technologies.

The two properties (low voltage and reduced delay) increase the efficiency of the devices manufactured using the transistors. With FinFET technology, transistors can also be designed with two functional gates. The gates are electrically independent of each other. The development has enabled designers to produce models that are more efficient and that have low-power gates.

FinFET technology has also enabled developers to reduce the size of transistors manufactured. The reduction in size does not affect the performance of the device. The smallest transistor produced by the use of the technology is 20 nanometers in size. In spite of this tiny size, the transistor has a number of valuable properties, such as leakage current and multi-gate features. The designers of these transistors have achieved this through the use of a three dimensional structure, which rises above the planar substrate. The design increases the volume of the structure without necessarily increasing the area of the planar substrate. Designing the transistors also requires the use of advanced technology. For instance, Technology Computed-Aided Design (TCAD) tools are used in modeling the transistors.³ The use of advanced technology in the manufacture of these transistors ensures that minimal room is left for error. As a result, better results are obtained, which improves the quality of devices manufactured using transistors made using the FinFET technology.

With FinFET technology, switching performance of electrical devices is improved.⁵ Increased switching performance is of great importance in electrical devices that carry out heavy tasks within a limited period of time. Such electrical devices include, among others, those involved in computing. For instance, the Intel Corporation, a multinational company involved in the manufacture of semiconductor chips, has adopted the use of FinFET technology. The company has used semiconductors produced through FinFET technology since 2012. The use of this technology by such a large firm is an indicator of its positive attributes in the production of electrical devices.

A number of factors contribute to the widespread use of semiconductors manufactured using FinFET technology. The factors include, among others, improved utilization of power and enhanced swing.⁶ FinFET technology also reduces impurity scattering and surface scattering in the semiconductors. As a result, dopant fluctuations are reduced or eliminated from the semiconductors.³ Higher on-current is also maintained while leakage is minimized in the semiconductors. As a result, the efficiency of the devices manufactured using these transistors is enhanced. Reduced impurity scattering and leakage of current associated with the use of the FinFETs also translates to lower power consumption.

The design of the FinFET transistor used by Intel is, however, slightly different from that of the conventional transistor. For example, the transistor has a rather unusual triangular shape. Traditionally, FinFETs are rectangular in shape.⁶ The chips containing the Intel-made transistors are yet to be availed in the market. However, scientists around the globe have termed the use of such chips as revolutionary. The chips have great potential in terms of improving the quality of new devices produced using the technology. It appears that FinFET is the future in the production of semiconductors. The triangular design of the new FinFETs will help in improving the structural strength of the new transistors. The triangular design’s improved switching performance is attributed to its design. The triangular prisms of the design, when compared to the rectangular prisms of the traditional design, have a higher area-volume ratio thus increasing the surface area in which the electrons flow.

In addition, the FinFET designed transistor for Intel is capable of quickly switching between the on and the off state. The transistor is designed in such a way that when it is in the on state, as much current as possible flows through it. However, when in the off state, close to zero current is allowed to pass through. Since chips are made by the use of many transistors connected together, high switching rate ensures improved performance of the devices made using FinFET transistors.⁵ Wastage of power is minimized as a result of the high switching rate, making the devices efficient consumers of power.

Compared to other technologies, FinFET has a better electrical control over the channels. The property is achieved through the use of a channel surrounded by a number of gates placed on multiple surfaces.⁵ As a result, the off state leakage current of the transistors is reduced. The reason is that less idle power is required when the transistor is not in ‘on’ state. There are basic working principles of the FinFET designed transistors with regards to power efficiency. One of the principles is to ensure that there is enhanced current passage in the on state and minimal leakage in the off state.

Conclusion

Semiconductors are important in the manufacture of electrical devices.⁶ Generally, a good semiconductor has poor electrical conductivity properties and to achieve this, a lot of physics principles are used. The reason for this is that it has just the right number of electrons required to complete the covalence bonds. However, through a number of techniques, such as doping and gating, semiconductors can be improved to n-type design. The new design has more electrons than the first one. The semiconductors can also be improved to P-type design. The design is characterized by electron deficiency. Through the use of such techniques, electric current is manipulated within devices. The manipulation spurs the device’s intended action. Research conducted over the years for the purposes of improving the quality of semiconductors has led to the invention of new and more effective designs. One of such new technologies that has aided in the production of semiconductors is FinFET. Significant progress has been achieved in the production of semiconductors through this technology. Such improvements are especially in the production of microchips and transistors.

References

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