Building advanced microchips becomes more economical thanks to Nvidia technology

Nvidia is showing cuLitho: a technology that aims to dramatically speed up the production of advanced microchips by removing a bottleneck in the lithography process.

There are practical objections between dream and reality, and so also between chip design and chip production. One of those objections can be found in the crucial lithography process, and Nvidia is proud to announce at GTC 2023 that it has a solution. The company is talking about a breakthrough in computer lithography with a technology it calls cuLitho.

What is the problem

Lithography is the process by which microchips are built. A microchip is first designed digitally. This design is then broken down into layers, and each layer ends up on a photomask. By irradiating a wafer with light along this mask, the components of a microchip are built up layer by layer. This process has been used to build microchips for decades, but it’s becoming increasingly complex.

Individual components on a chip are becoming ever smaller, which means that the drawings on the photomasks are also becoming ever smaller and more complex. The mask used to be irradiated with visible light, but its wavelength is now much larger than the size of the details on the mask. Try coloring a coloring book with a paint roller for the wall.

The solution is twofold: On the one hand, manufacturers such as the Dutch lithography specialist ASML are looking for finer brushes. Today, the photo masks are not irradiated with visible light, but with extreme UV radiation. After all, it has a smaller wavelength.

It’s still not perfect. When the light waves go through the mask to the wafer, there is still a deviation. The solution to this is to readjust the photomask a little so that it proactively takes into account the deviation in the irradiation so that the EUV light still falls exactly on the wafer. Fitting this mask requires back-calculation of the behavior of the radiation, which is a complex task requiring weeks of computation time. Each adjustment of a production line also implies that the irradiation takes place differently and therefore a mask has to be recalculated.

computer lithography

This calculation is called Computational Lithography and Nvidia’s breakthrough with cuLitho makes the calculation process much faster. New algorithms in combination with Nvidia Hopper GPUs ensure that a photo mask is calculated around 40 times faster. What used to take a week or two can now be done in less than a night.

This gives chip manufacturers the opportunity to convert their production lines much more quickly. The entire development cycle of a new microchip can be adjusted in this way, and the environment is also grateful. After all, weeks of energy-consuming computing time in a data center are no longer necessary.

Nvidia brings cuLitho onto the market together with the big chip builders. ASML has already indicated that it will make all of its tools compatible with Nvidia GPUs and TSMC is also enthusiastic.