METHOD OF LASER PLASMA-CHEMICAL CUTTING OF PLATES Russian patent published in 2020 - IPC H01L21/302 

FIELD: chemistry.

SUBSTANCE: invention relates to laser methods of cutting (fragmentation) of plates on crystals and can be used in microelectronic industry for fragmentation of plates with devices made on them. Method of laser fragmentation of sapphire substrates provides focusing of laser radiation on processed surface in atmosphere in gas medium, containing hydrogen (H₂), or a gas mixture of hydrogen (H₂) with hydrogen chloride (HCl) (H₂ + HCl), or a gas mixture of argon (Ar) and hydrogen chloride (HCl) (Ar + HCl), or a gas mixture of hydrogen (H₂) with hydrogen chloride (HCl) and argon (Ar) (H₂ + Ar + HCl), wherein chemical reactions are initiated by both thermal processes of dissociation of gas components, and due to formation of plasma in atmosphere of pure hydrogen (H₂) or mixture of argon with hydrogen chloride (Ar + HCl) at pressure from 760 Torr (atmospheric) to 1⋅10^-3 Torr.

EFFECT: technical result is precision fragmentation without "ejection" and reprecipitation of substrate material on formed devices, walls and windows of process chamber.

1 cl