摘要:
A device is disclosed which may comprise a system generating a plasma at a plasma site, the plasma producing EUV radiation and ions exiting the plasma. The device may also include an optic, e.g., a multi-layer mirror, distanced from the site by a distance, d, and a flowing gas disposed between the plasma and optic, the gas establishing a gas pressure sufficient to operate over the distance, d, to reduce ion energy below a pre-selected value before the ions reach the optic. In one embodiment, the gas may comprise hydrogen and in a particular embodiment, the gas may comprise greater than 50 percent hydrogen by volume.
摘要:
Systems and methods are disclosed for reducing the influence of plasma generated debris on internal components of an EUV light source. In one aspect, an EUV metrology monitor is provided which may have a heater to heat an internal multi-layer filtering mirror to a temperature sufficient to remove deposited debris from the mirror. In another aspect, a device is disclosed for removing plasma generated debris from an EUV light source collector mirror having a different debris deposition rate at different zones on the collector mirror. In a particular aspect, an EUV collector mirror system may comprise a source of hydrogen to combine with Li debris to create LiH on a collector surface; and a sputtering system to sputter LiH from the collector surface. In another aspect, an apparatus for etching debris from a surface of a EUV light source collector mirror with a controlled plasma etch rate is disclosed.
摘要:
Systems and methods are disclosed for protecting an EUV light source plasma production chamber optical element surface from debris generated by plasma formation. In one aspect of an embodiment of the present invention, a shield is disclosed which comprises at least one hollow tube positioned between the optical element and a plasma formation site. The tube is oriented to capture debris while allowing light to pass through the tube's lumen via reflection at relatively small angles of grazing incidence. In another aspect of an embodiment of the present invention, a shield is disclosed which is heated to a temperature sufficient to remove one or more species of debris material that has deposited on the shield. In yet another aspect of an embodiment of the present invention, a system is disclosed which a shield is moved from a light source plasma chamber to a cleaning chamber where the shield is cleaned.
摘要:
An EUV light source is disclosed which may comprise at least one optical element having a surface, such as a multi-layer collector mirror; a laser source generating a laser beam; and a source material irradiated by the laser beam to form a plasma and emit EUV light. In one aspect, the source material may consist essentially of a tin compound and may generate tin debris by plasma formation which deposits on the optical element and, in addition, the tin compound may include an element that is effective in etching deposited tin from the optical element surface. Tin compounds may include SnBr4, SnBr2 and SnH4. In another aspect, an EUV light source may comprise a molten source material irradiated by a laser beam to form a plasma and emit EUV light, the source material comprising tin and at least one other metal, for example tin with Gallium and/or Indium.
摘要:
Systems and methods are disclosed for reducing the influence of plasma generated debris on internal components of an EUV light source. In one aspect, an EUV metrology monitor is provided which may have a heater to heat an internal multi-layer filtering mirror to a temperature sufficient to remove deposited debris from the mirror. In another aspect, a device is disclosed for removing plasma generated debris from an EUV light source collector mirror having a different debris deposition rate at different zones on the collector mirror. In a particular aspect, an EUV collector mirror system may comprise a source of hydrogen to combine with Li debris to create LiH on a collector surface; and a sputtering system to sputter LiH from the collector surface. In another aspect, an apparatus for etching debris from a surface of a EUV light source collector mirror with a controlled plasma etch rate is disclosed.
摘要:
The present invention provides a reliable, high-repetition rate, production line compatible high energy photon source. A very hot plasma containing an active material is produced in vacuum chamber. The active material is an atomic element having an emission line within a desired extreme ultraviolet (EUV) range. A pulse power source comprising a charging capacitor and a magnetic compression circuit comprising a pulse transformer, provides electrical pulses having sufficient energy and electrical potential sufficient to produce the EUV light at an intermediate focus at rates in excess of 5 Watts. In preferred embodiments designed by Applicants in-band, EUV light energy at the intermediate focus is 45 Watts extendable to 105.8 Watts.
摘要:
The present invention provides a reliable, high-repetition rate, production line compatible high energy photon source. A very hot plasma containing an active material is produced in vacuum chamber. The active material is an atomic element having an emission line within a desired extreme ultraviolet (EUV) range. A pulse power source comprising a charging capacitor and a magnetic compression circuit comprising a pulse transformer, provides electrical pulses having sufficient energy and electrical potential sufficient to produce the EUV light at an intermediate focus at rates in excess of 5 Watts. In preferred embodiments designed by Applicants in-band, EUV light energy at the intermediate focus is 45 Watts extendable to 105.8 Watts.
摘要:
A method and apparatus for debris removal from a reflecting surface of an EUV collector in an EUV light source is disclosed which may comprise the reflecting surface comprises a first material and the debris comprises a second material and/or compounds of the second material, the system and method may comprise a controlled sputtering ion source which may comprise a gas comprising the atoms of the sputtering ion material; and a stimulating mechanism exciting the atoms of the sputtering ion material into an ionized state, the ionized state being selected to have a distribution around a selected energy peak that has a high probability of sputtering the second material and a very low probability of sputtering the first material. The stimulating mechanism may comprise an RF or microwave induction mechanism.
摘要:
An apparatus and method is described which may comprise a plasma produced extreme ultraviolet (“EUV”) light source multilayer collector which may comprise a plasma formation chamber; a shell within the plasma formation chamber in the form of a collector shape having a focus; the shell having a sufficient size and thermal mass to carry operating heat away from the multilayer reflector and to radiate the heat from the surface of the shell on a side of the shell opposite from the focus. The material of the shell may comprise a material selected from a group which may comprise silicon carbide, silicon, Zerodur or ULE glass, aluminum, beryllium, molybdenum, copper and nickel. The apparatus and method may comprise at least one radiative heater directed at the shell to maintain the steady state temperature of the shell within a selected range of operating temperatures.
摘要:
An apparatus and method for EUV light production is disclosed which may comprise a laser produced plasma (“LPP”) extreme ultraviolet (“EUV”) light source control system comprising a target delivery system adapted to deliver moving plasma initiation targets and an EUV light collection optic having a focus defining a desired plasma initiation site, comprising: a target tracking and feedback system comprising: at least one imaging device providing as an output an image of a target stream track, wherein the target stream track results from the imaging speed of the camera being too slow to image individual plasma formation targets forming the target stream imaged as the target stream track; a stream track error detector detecting an error in the position of the target stream track in at least one axis generally perpendicular to the target stream track from a desired stream track intersecting the desired plasma initiation site. At least one target crossing detector may be aimed at the target track and detecting the passage of a plasma formation target through a selected point in the target track. A drive laser triggering mechanism utilizing an output of the target crossing detector to determine the timing of a drive laser trigger in order for a drive laser output pulse to intersect the plasma initiation target at a selected plasma initiation site along the target track at generally its closest approach to the desired plasma initiation site. A plasma initiation detector may be aimed at the target track and detecting the location along the target track of a plasma initiation site for a respective target. An intermediate focus illuminator may illuminate an aperture formed at the intermediate focus to image the aperture in the at least one imaging device. The at least one imaging device may be at least two imaging devices each providing an error signal related to the separation of the target track from the vertical centerline axis of the image of the intermediate focus based upon an analysis of the image in the respective one of the at least two imaging devices. A target delivery feedback and control system may comprise a target delivery unit; a target delivery displacement control mechanism displacing the target delivery mechanism at least in an axis corresponding to a first displacement error signal derived from the analysis of the image in the first imaging device and at least in an axis corresponding to a second displacement error signal derived from the analysis of the image in the second imaging device.