The principle of steady-state micro-bunching has been verified, and domestic lithography machines may usher in new development

On February 25, 2021, Professor Tang Chuanxiang's research group from the Department of Engineering Physics of Tsinghua University and the cooperative team published a research paper entitled 'Experimental Demonstration of Steady-State Microbunching Principle' in 'Nature', reporting a new particle accelerator light source“steady state microbunching”(SSMB) proof-of-principle experiments. SSMB works by first sending a beam of electrons into a ring accelerator. When the electrons are running, the accelerator's magnetic field causes the electrons to change their direction of motion and release synchrotron radiation. The amplitude becomes smaller and smaller, and the size of the electron beam becomes smaller and smaller. The research team's experiments proved that the optical phases of the electrons can be correlated turn by turn with an accuracy shorter than the laser wavelength, so that the electrons can be stably comforted in the optical potential well formed by the laser. This achievement has attracted great attention from the international community, mainly because one of the potential applications of the SSMB light source is as a light source for future EUV lithography machines. Researcher Tang Chuanxiang pointed out that the EUV light source based on SSMB achieves higher average power, which provides a new solution for the breakthrough of high-power EUV light source. And this technology effectively solves the core problem of lithography machine research and development. Lithography machine, also known as mask alignment exposure machine, exposure system, lithography system, etc., uses a technology similar to photo printing to print the fine patterns on the mask onto the silicon wafer through light exposure. At present, as the main manufacturer of lithography machine production——ASML uses a high-energy pulsed laser to bombard a liquid tin target to form a plasma and then generate an EUV light source with a wavelength of 13.5 nanometers. The EUV light source based on SSMB is expected to achieve greater average power, which stimulates the expansion potential of shorter wavelengths, which can provide a new solution for the breakthrough of high-power EUV light sources, and then develop more chips of 5nm and below. . Lithography machine is the main tool in chip production, but my country's lithography technology not only lags behind Western countries, but also difficult to independently use for chip production. Restricted by the level of domestic technology and the import of lithography machines, my country's chip R&D and production process is also far behind foreign countries, but the SSMB technology released this time can be said to have laid a technical foundation for EUV lithography machines, which will not be used in the future.“stuck neck”Removed an obstacle. It is believed that after the SSMB light source can be applied to the field of EUV lithography, domestic EUV lithography machines may usher in development hope.