After five decades of Moore’s Law, an observation which states that computational power doubles every two years, silicon-based Complementary Metal Oxide Semiconductor (Si-CMOS) has cemented its place as the mainstream logic technology. We have become accustomed to the rapid increase in computational power, expecting our new mobile phones, computers and even fridges to perform faster and accomplish more computationally intensive tasks every year. This expectation has largely been fulfilled through increasing the density of transistors - tiny switches which control the system of zeros and ones governing classical computing.

We have increased the density of transistors primarily through shrinking them. Today’s logic devices are a spectacular display of human ingenuity, spanning just tens of atoms in length. However, we are now approaching a period where it is impossible to shrink these devices further - impossible with Si-CMOS. New transistor geometries such as Gate-All-Around Nanowire (GAA) and 3D Through-Silicon Via (3D TSV) will help extend CMOS, whereas new materials such as graphene and Transition Metal Dichalcogenides (TMDCs) as well as new technologies such as Tunneling Field Effect Transistors (TFETs) have the potential to take us into a new era of computing, beyond CMOS. Although all these technologies have seen rapid progress, due to economic and time constraints, only a select few will help continue the exponential increase in computing power.