Is Moore’s law dead?

Moore's law predicts that the number of transistors on a microchip doubles approximately every two years. It’s held true for over five decades. We’ve witnessed continuous improvements in performance and efficiency, enabling exponential growth of computing power. However, as we approach the physical limits of traditional silicon-based technology, many are asking: is Moore's law dead?

This question reflects a growing concern of a semiconductor industry faced with massive challenges that come with further scaling down transistor size to fit more and more of them onto a chip.

The end of Moore’s law? The challenges of linear transistor scaling

As transistors have shrunk to sizes approaching just a few nanometers, several roadblocks have emerged that make further scaling increasingly difficult. These challenges include:

1. Physical limits: As transistors become smaller, quantum effects cause electrons to start behaving in unexpected ways (causing electron tunneling and leakage currents). This leads to higher energy use and heat generation, which affect both performance and efficiency.
2. Cost and complexity: The cost of developing and manufacturing cutting-edge microchips has skyrocketed. Next-generation fabrication technologies, such as extreme ultraviolet (EUV) lithography, are extremely expensive and require highly specialized equipment. This makes it increasingly difficult for companies to achieve the economies of scale that previously drove Moore's law. In other words, where ‘smaller’ chips used to mean ‘cheaper’ chips, this no longer invariably holds true.
3. Material constraints: Silicon, the traditional material used in semiconductor manufacturing, is reaching its limits in terms of performance and scalability. As transistor dimensions shrink, the electrical properties of silicon are no longer sufficient to maintain the desired levels of performance.

These hurdles have led some to believe that we are witnessing the end of Moore's law as the straightforward doubling of transistor density becomes less feasible. They fear Moore’s law will be slowing down. Or worse, can be declared dead altogether.

Extending Moore’s law: next-gen lithography and new device concepts

Despite the growing difficulties, efforts are still underway to extend the principles of Moore's law through innovative technologies and approaches.

Next-generation lithography methods, such as extreme UV (EUV) lithography and high-numerical aperture EUV lithography, are being developed to achieve smaller and more precise patterns on silicon wafers. These technologies allow for the continued scaling of transistors, albeit at a much higher cost and with dazzling complexity.

Researchers are also exploring new device architectures, such as gate-all-around transistors and nanosheet transistors, which offer better control over electrical characteristics at smaller scales. These novel designs could enable further transistor scaling, even as traditional planar transistors reach their limits.

Another approach to ensure the continuity of Moore's law is through 3D integration, where multiple layers of transistors are stacked on top of each other. This method increases the transistor density without shrinking their size. It offers a way to enhance performance and efficiency within the same footprint.

As we move away from linear scaling—where chips are scaled down uniformly—we will need to leverage all these different approaches. We must create more versatile and customized chips that are designed to better meet the different requirements for specific applications. Constraints related to energy use, cost, temperature, or speed are very different for chips for smartphones, for example, compared to those for high-performance computing, or for virtual reality systems.

The goal is to make chips that can handle a wide variety of applications by smartly dividing their functions across multiple layers. At imec, we call this approach CMOS 2.0. We believe it holds the key to continued advancement of technology in an increasingly diverse and demanding environment.

Learn more about CMOS 2.0

Beyond Moore’s law: taking an alternative route

As the traditional scaling paradigm slows down, the industry is also exploring alternative routes that could redefine the future of computing altogether. Some of these approaches include:

• New materials: Materials beyond silicon, such as graphene and transition metal dichalcogenides, are being investigated for their superior electrical properties. These materials could offer faster and more efficient transistors, potentially enabling the continuation of Moore's law in a new form.
• Neuromorphic computing: Inspired by the human brain, neuromorphic computing seeks to develop chips that mimic the brain's neural networks. This approach could lead to more efficient and powerful processors, especially for tasks involving artificial intelligence and machine learning.
• Quantum computing: Perhaps the most promising frontier beyond Moore's law is quantum computing. Unlike classical computers, which use bits to represent data as 0s and 1s, quantum computers use qubits, which can represent both 0 and 1 simultaneously. This capability could enable quantum computers to solve problems that are currently intractable for classical systems, offering a new paradigm for computing power.

Conclusion: Is Moore's law still valid?

Moore's law in its traditional interpretation may be slowing down. But the spirit of innovation that it represents continues to drive the semiconductor industry, and definitely everyone at imec. Is Moore's law still valid? In some ways, yes—but it’s evolving. As we approach the physical and economic limits of traditional scaling, the industry is pivoting to new technologies and approaches. These could sustain or even surpass the progress predicted by Moore’s law.

The end of Moore's law in its classic sense may be near, but the pursuit of ever-greater computing power is far from over. Whether through next-generation lithography, alternative materials, innovative design, or revolutionary concepts like quantum computing, the future of technology promises to be as transformative as ever.