EUV Technology
- [EUV Lithography - ASML]
- Overview
EUV lithography is a soft X-ray technique with a wavelength of 13.5nm. Today's EUV scanners can achieve resolutions down to 22nm half-pitch. In one system, the EUV light source utilizes a high-power laser to generate the plasma. This in turn helps emit short wavelength light inside the vacuum chamber. In the chamber, the system uses multiple multilayer mirrors that reflect light through interlayer interference.
EUV was originally planned to be introduced at the 45/40nm process node, but power issues to achieve sufficient throughput caused multiple delays. It is considered a key component for 16/14nm as a way to avoid double patterning with 193nm immersion. EUV systems are starting to be used on the 7nm process.
At 7nm, EUV is capable of single-pass patterning, but with today’s resists, the operation is relatively slow and can cause unwanted random or random defects in the pattern that affect yield.
At 5nm, even with EUV, double patterning on critical layers is required. Even though it requires a more expensive step, double patterning means that the spacing of features can be relaxed and then processed, which can reduce the number of defects.
- Extreme Ultraviolet Lithography
Extreme ultraviolet lithography (also known as EUV or EUVL) is an optical lithography technique used in steppers, machines that make integrated circuits (ICs) for computers and other electronic devices. It uses a range of extreme ultraviolet (EUV) wavelengths, roughly spanning a 2% FWHM bandwidth of about 13.5 nm, to create patterns by exposing a reflective photomask to UV light, which is reflected onto a photoresist-covered substrate. It is widely used in the manufacturing process of semiconductor devices.
Using EUV light, ASML's NXE system provides high-resolution lithography and enables mass production of the world's most advanced microchips. The machine that keeps Moore's Law alive. ASML's next-generation EUV lithography machine achieves a level of precision previously unattainable, meaning chips can continue to shrink for years to come.
As of 2022, ASML Holdings is the only company producing and selling EUV systems for chip production, targeting 5nm and 3nm. At the 2019 International Electron Devices Meeting (IEDM), TSMC reported 5 nm using EUV in contact layers, vias, metal lines, and dicing layers, where dicing can be applied to fins, gates, or metal lines. At IEDM 2020, TSMC reported a 30% reduction in its 5nm minimum metal spacing compared to 40nm at 7nm. Samsung's 5nm is lithographically identical to the 7nm design rules, with a minimum metal pitch of 36nm.
