Magnetic field extends mirror lifetime in EUV litho

Article By : EE Times Asia

Gigaphoton's magnetic-field debris mitigation technology extends collector mirror lifetime with a reflectance decrease of less than 0.5% per billion pulses.

Gigaphoton has developed a debris mitigation technology using magnetic fields in extending the lifetime of collector mirrors in pilot light sources designed to operate semiconductor mass production lines.

EUV light source equipment concentrates light generated by high-intensity EUV plasma, and requires collector mirrors to then transmit this light to lithography equipment. However, when operating at high output rates the mirrors soon become contaminated with the tin being targeted by the mirror's light that leads to exceedingly short lifespans of collector mirrors. This challenge has been a major barrier for their practical application.

Gigaphoton has verified its patented technology that uses magnetic fields to mitigate debris, extends the lifetime of collector mirrors (with a reflectance decrease of less than 0.5% per billion pulses). These experiments involved the magnetic-field debris mitigation technology installed onto an EUV lithography pilot light source equivalent to one typically used in a mass production plant, and then operated at 100W. The data suggests that the lifespan of collector mirrors that was previously only a few weeks under continuous operation, can be extended.