EUV: The Quiet Revolution in DRAM Speaks Volumes for the Future
on Aug 31, 2020
Smaller, faster, better. The DRAM market has always been about miniaturization and improvement. It’s never been like this simply because manufacturers want to show that they can, it’s because there’s always a need to innovate and improve on the previous generation. The latest innovation is ready for prime time and will drastically change the way devices look and function. The technology that is enabling all of this is Extreme Ultraviolet (EUV) lithography.
The memory market is a competitive one. Yet no revolutionary measures that truly shake up the industry can be rolled out overnight. It’s therefore vital to prepare now for tomorrow. EUV provides a bright future for DRAM but it’s Deep Ultraviolet (DUV) lithography that’s currently being used throughout the industry. DUV works well for current generations of semiconductors. However, with the commercial rollout of EUV starting to take place, it’s time to dream big about addressing the limitations of current processes and fabricating memory in new ways.
The new EUV world
Look around you and you’ll probably see a piece of technology that connects to a wider network of devices. And indeed, it’s the growth of IoT, AI and 5G that is requiring changes to the way that DRAM is developed. Memory now needs finer processing and the incredibly fine ultraviolet light used in the EUV process is just what the industry needs to create DRAM solutions that will be rolled out widely over the coming years.
EUV is a matter of scale. Look at Moore’s Law, which promises a doubling of processor speeds or overall processing power for computers every two years. Despite the adherence to this rule we have seen in the past, this is getting increasingly difficult. The continual task at the top of researchers’ minds has been enabling memory to store more capacity within the same area and size to meet the increasing demands for high capacity memory in the future.
EUV brings about a number of advantages thanks to the unique approach to lithography that it enables. Whereas previously, the industry largely relied on iterative improvements, the breakthrough enabled by EUV will be game changing.
Lithography in semiconductor manufacturing is similar to film photography. It uses light to transfer an image to a substrate, which in the case of lithography is a silicon wafer. The process works by the light passing through a mask which contains a stencil of the circuit pattern and a series of optical lenses to shrink down the image and project it onto the silicon. The circuit pattern remains on the wafer after additional light and chemical processes take place.
A leap forwards
Here’s the difference. Whereas DUV lithography makes use of 193nm wavelengths, EUV lithography uses wavelengths at 13.5nm – quite the improvement. This enables the drawing of finer circuitry and thus more data can be stored within the same surface area. Making the circuitry finer means more logical gates are able to fit inside a single chip. Those chips in turn become more powerful and energy efficient as a result. The surface area of a chip is used much more effectively when EUV is deployed so it’s no wonder why so many in the industry are clamoring to perfect the technology for their own fabrication lines.
The resulting chips made using the EUV process are small but mighty, more compact yet highly powerful. This means enhanced processing and productivity. It also means more versatility within applications such as smartphones, IoT devices and servers, where the size to power ratio is important, and efficiency is also at a premium.
There’s an additional advantage too. DUV processes typically use multiple masks to create a single wafer because the complexity of the circuits required for today’s chips is too high to only use a single mask. With EUV, however, the circuits can be drawn in smaller, and more detailed formations, which means seamless single patterning can be used. The more masks that are used, the more process steps are required. This lengthens the production lead time and therefore time to market. Single patterning ultimately produces better yields and saves time and cost for customers.
First mover advantage
Samsung has the upper hand in EUV procedures. It is one of the first in the industry to successfully apply EUV processing to DRAM production thanks to its superior semiconductor manufacturing technology and expertise. Samsung has already been mass producing specific EUV applied products and is preparing to ramp up its capacity to manufacture on a larger scale in the near future.
Earlier this year, Samsung announced it had shipped a million of the 10nm-class (D1x) DDR4 (Double Date Rate 4) DRAM modules based on EUV technology. The modules had completed global customer evaluations and this milestone opens the door to more cutting edge uses of EUV to create solutions for a number of applications such as premium PC, mobile, enterprise servers and data centers.
Mass production started at the new Samsung semiconductor fabrication line in Hwaseong, Korea at the start of this year – Samsung’s first production line dedicated to EUV technology. Now, Samsung is pushing the technology boundaries even further, having just launched the first large-scale production line for 16 Gb LPDDR5 Mobile DRAM chips based on 10-nm-class process technology. Samsung is the first in the industry to apply EUV for this process.
Samsung’s name isn’t just associated with industry leading products; it also has the trust built from a history of innovation and high-quality. The company was quick off the mark because it has been preemptively applying EUV processes in the device solutions sector, knowing early on that EUV is the future.
This is a journey, and the destination hasn’t yet arrived. Samsung knows this and is therefore taking steps to iron out any defects now so that it is ready for the future. The company has a roadmap whereby it is preparing to deploy more widely DRAM solutions that have used EUV processes.
EUV has huge potential today and large amounts of applications it will transform in the future, but after that who knows? Providing benefits to customers, as well as to the industry as a whole, is at the forefront of everything Samsung works to achieve.