As one of the key equipment in the chip manufacturing process, the type of lithography machine is inextricably related to the process. The dry DUV lithography machine uses a deep ultraviolet light source with a wavelength of 193nm, which is suitable for manufacturing chips from 130nm to 65nmThe immersion DUV lithography machine is used to fabricate chips from 65nm to 7nm by refracting the light source to 134nm after the wavelength is changed to 134nm. As for the EUV lithography machine, 13Extreme ultraviolet light source with a wavelength of 5nm is mainly used to make chips of 5nm and below. It can be seen that the improvement of the accuracy of the lithography machine is closely related to the wavelength of the light source. The smaller the wavelength of the light source, the higher the accuracy, and the smaller the chip process can be manufactured.
However, with the development of technology, 13The 5nm EUV lithography machine is already approaching the limit of wavelength, and it is no longer possible to reduce the wavelength further. If the wavelength is further reduced, there will be a huge loss of light energy, and it will be difficult to adjust the reflection angle, which will make lithography impossible. If the problem of insufficient light energy is to be solved, it is necessary to increase the input of light energy, which will lead to the enlargement of the mirror and the huge volume of the light source system, which is not conducive to production and transportation. Therefore, in addition to the problem of the wavelength of the light source, the resolution of the lithography machine can also be improved from two aspects: numerical aperture and lithography process factor.
The numerical aperture (NA) represents how much light a lithography system can collect and focus. As a manufacturer of lithography machines, ASML has set its sights on the improvement of numerical aperture in the process of continuous pursuit of technological breakthroughs. With the innovation of technology, the numerical aperture of several generations of ASML lithography machines has been continuously increased, from the initial 025 to 033。ASML says that the next generation of EUV lithography machines will have a numerical aperture of 055, which may be the last limit of lifting. Because once it reaches 0After 55, it will be extremely difficult to further increase the numerical aperture.
In addition to the increase in numerical aperture, the lithography process factor is also one of the key factors in improving the resolution of the lithography machine. The lithography process factor (k1) represents the proportional relationship between the graphic resolution and the resolution of the optical projection system. ASML's EUV lithography machine has successfully broken through the theoretical limit of 025 lithography process factors. However, ASML's co-CEO said that it was quite difficult to further break through the lithography process factor, and that all partners needed to work together, and ASML was not too sure about this.
Recently, ASML announced that co-presidents Wennink and Van den Brink will retire in April next year. Retired CEOs are leaving ASML, raising concerns about the future direction. In the context of lithography machine technology gradually reaching a bottleneck, ASML needs to find a new breakthrough. For ASML, possible development directions include, but are not limited to, in-depth research into optical technology to further improve the resolution of lithography machinesIncrease investment in research and development of new materials and processes, and promote innovation in chip manufacturing processes;Strengthen cooperation with partners to jointly solve technical challenges, etc. Although the departure of the CEO has brought some uncertainty to ASML, as the world's leading lithography machine manufacturer, ASML has strong R&D strength and technology accumulation, and believes that it can meet the challenges of the future.
Summary: As a crucial piece of equipment in the chip manufacturing process, the continuous improvement of the accuracy of the lithography machine is closely related to factors such as wavelength, numerical aperture and lithography process factor. However, with wavelengths approaching the limit and numerical apertures and lithography process factors being challenged, lithography machine technology has entered a critical juncture. In this context, ASML, as a leader in the lithography machine industry, faces significant challenges and opportunities. How to break through the technical bottleneck and find a new development direction, after the new CEO takes office, ASML will continue to play an important role in the global chip manufacturing field. However, in any case, the development of lithography machine technology still requires cooperation and collaborative efforts between the upstream and downstream of the global chip industry chain.