to build an EUV light system for lithography. The laser system will be very daunting taskuse quantum cascade semiconductor laser as seeding oscillator the generate nansecond pulse and then applied through commercial Co2 high power laser that use for welding and cutting. Its called Master Oscillator Amplifier power laser
the power laser hit evaporate tin droplet liquid at 40,000 times a second to create plasma that generate EUV light
That's the area US government will try to block China from acquiring that.
[size=14.6667px]Zoomed in Amplifer section that pumps up to the 20KW (used Mitsubishi Electric traditional FTF laser for cutting and welding)
[size=14.6667px]The system comprised a pulsed seed laser at 1064nm and two stages of amplifiers called pre-amplifier and a power amplifier, both based on Nd:YVO 4 gain medium in the bounce geometry configurations.
[size=14.6667px]1)The pulsed seed source used in this system was a semiconductor laser diode. The laser diode was connected to a pulsed electrical driving circuit for gain-switched operation. The electrical drive circuit was capable of generating an optical pulse durations from 3.5ns to over 10us with adjustable pulse repetition rate, ranging from single shot up to 2MHz.
[size=14.6667px]*)The wavelength of the laser diode was therefore tuned using a diffraction grating.
[size=14.6667px]2)The pre-amplifier and power amplifier were both based on 1.1 at. % Nd:YVO 4 crystal using bounce geometry configuration. The crystal was side-pumped by a laser diode bar emitting at 808nm, which was anti-reflection (AR) coated for the pump wavelength. The two end laser faces were AR coated at 1064nm. The heat was removed from the top and bottom faces of the crystal using water-cooling
Two pulse lasers used. First one is pre-pulse and second is main pulse.
When an Sn droplet target is irradiated with pre-pulse laser and/or CO 2 laser beams, the Sn droplet in the vessel is con-
verted into a plasma-emitting EUV where several states of Sn exist simultaneously. The different Sn states are generally
classified as fragments, neutral atoms, or ions. All fragments are vaporized by main pulse.
Now, China big Fund investment started to withdraw investment on some of the China IC firms. The sector is overheated with too many similar players.
Actually, some IC firms are shams or scams for government funding. Way too many of them going Fabless route,design AI chips, CPU, all digital chips and hand off to taiwan and korea for manufacturing. Some of the more establishes ones are also fabless, Huawei, ZTE, Loongson, Shenwei, Rockchip, Allwinner, Zhaoxin, etc.
I start to think now that going Fabless doesn't really give China the needed value which is the patchup of weakness in semiconductor manufacturing,