Abstract: Embodiments of the present invention provide an apparatus employing an electron beam to expose the structure of a micro device and produce an image of the structure. The apparatus includes an electron gun producing the electron beam; an electron beam column having one or more segments that shape, focus and/or deflect the electron beams; and one or more center tubes along the electron beam column that provides a high vacuum environment for and guiding the electron beam to a target object coated with an electron sensitive resist. At least one of the center tubes is a carbon tube made of solid carbon material.

Abstract: Embodiments of the present invention provide an apparatus employing an electron beam to expose the structure of a micro device and produce an image of the structure. The apparatus includes an electron gun producing the electron beam; an electron beam column having one or more segments that shape, focus and/or deflect the electron beams; and one or more center tubes along the electron beam column that provides a high vacuum environment for and guiding the electron beam to a target object coated with an electron sensitive resist. At least one of the center tubes is a carbon tube made of solid carbon material.

Abstract: A method and apparatus for clamping a semiconductor mask to a carrier device is taught. The apparatus is comprised of a base member to which is attached an elongated spring. Both the base and the spring have affixed to them a means for compressively contacting the mask surface when the mask is put in place. In the preferred embodiment, that contact means is made of sapphire shaped in the form of a dome. The clamp further includes an adjustment screw that can be used to adjust the height of the contact means affixed to the base member. In this manner, the surface of the mask can be adjusted so that it is planarized to the right orientation relative to an e-Beam or laser source that will be used to scribe a pattern on the mask. Finally, the clamp includes electrical contacts, and the materials out of which the clamp is made are deliberately selected, so that no electrical or magnetic forces can build up on the clamp or the wafer that might adversely affect the scribing process.

Abstract: A multi-beam e-beam system employs a set of independently controllable (for blanking and deflection) subsystems placed in a solenoid field, each system having a demagnifying lens comprising at least one passive pole piece, so that the final image demagnifies imperfections in the upstream electron beam. Upper and lower sections of the system employ the focusing effect of the solenoid field to form an image at a shaping aperture and a demagnified image of the beam at the shaping aperture on the workpiece. Small focus corrections due to magnetic lens field non-uniformity and/or target height variations, are accomplished with an electrostatic unipotental lens built into the pole pieces and target voltage variations.

Abstract: A method and apparatus for clamping a semiconductor mask to a carrier device is taught. The apparatus is comprised of a base member to which is attached an elongated spring. Both the base and the spring have affixed to them a means for compressively contacting the mask surface when the mask is put in place. In the preferred embodiment, that contact means is made of sapphire shaped in the form of a dome. The clamp further includes an adjustment screw that can be used to adjust the height of the contact means affixed to the base member. In this manner, the surface of the mask can be adjusted so that it is planarized to the right orientation relative to an e-Beam or laser source that will be used to scribe a pattern on the mask. Finally, the clamp includes electrical contacts, and the materials out of which the clamp is made are deliberately selected, so that no electrical or magnetic forces can build up on the clamp or the wafer that might adversely affect the scribing process.

Abstract: A multi-beam e-beam system employs a set of independently controllable (for blanking and deflection) subsystems placed in a solenoid field, each system having a demagnifying lens comprising at least one passive pole piece, so that the final image demagnifies imperfections in the upstream electron beam. Upper and lower sections of the system employ the focusing effect of the solenoid field to form an image at a shaping aperture and a demagnified image of the beam at the shaping aperture on the workpiece. Small focus corrections due to magnetic lens field non-uniformity and/or target height variations, are accomplished with an electrostatic unipotental lens built into the pole pieces and target voltage variations.

Abstract: A magnetic lens employs a solenoid field containing a passive pole piece that shapes the solenoid field to create a demagnifying lens that has very low geometrical aberrations by adjusting the field upstream and downstream of the gap between the pole pieces to create a negative term in the formula for spherical aberrations, subtracting a significant amount from the contribution to the aberrations that comes from the field in the gap.

Abstract: Forming poles from sectors of a tube of carbon or a material with similar conductive properties and supporting the poles by bonding an insulating support ring thereto before removing end rings formed at the ends of the tube which temporarily support the poles provides a multipole deflector element of robust structure of high dimensional accuracy and stability in which eddy current and charging effects are avoided. The manufacturing method is much simplified, reduced in cost and increased in reliability, repeatability and yield over manufacturing techniques for known multipole deflectors.

Abstract: Motion of a block carrying a grid for backscattering portions of a pattern of charged particles incident on the grid is moved generally axially of a charged particle beam tool while the position of the block is measured, preferably to optically, with a grazing incidence laser beam or interferometer, in the axial direction for any or all of the degrees of freedom of the block. Backscatter is correlated with known grid position to correct the backscatter measurement to compensate for lateral components of motion parallel to the target plane in measurement of actual beam position at different axial locations. Telecentricity and landing angle can thus be observed to an accuracy of 0.003 milliradians in substantially real time; permitting substantially real time adjustment thereof. The basic principles of this process and apparatus can be extended to measurement of numerical aperture and are equally applicable to probe-forming and beam projection lithography tools.

Abstract: A dynamic focus coil produces different selected ampere-turns while consuming constant power and therefore maintaining constant temperature. The focus coil comprises a set of coils that all consume the same power. A selected subset of coils (e.g. two or three) are energized at any given time, the subset being selected to produce the desired focus adjustment. Illustratively, the coils all have the same resistance and are driven by current having the same magnitude and selectable polarity. An alternative embodiment contains a “coarse” set of coils having selected values of ampere turns and a “fine” set of coils having values of ampere turns that fill in between the values of the coarse set.

Abstract: A scattering target for use in a particle beam system is formed from a grid of gold on a substrate of carbon, with an intermediate smoothing layer (e.g. copper) on the carbon to provide a surface sufficiently smooth to provide an adequate target. An optional bonding layer may be used to improve adhesion between the gold and the smoothing layer.

Abstract: The invention relates to a method and apparatus for measuring The landing angle of a particle beam is adjusted by scanning the beam over two cylindrical beam target surfaces that are positioned close to the system axis. The output of a beam detector is differentiated and displayed on an oscilloscope. The relevant lens current is adjusted until one side of the scan indicates that the focal plane of the beam is at the center of the beam target. The angle of the beam is then adjusted with the relevant deflector until both sides of the scan are the same, indicating that the beam is accurately vertical.

Abstract: An X-ray mask includes one or more X-ray transparent mask windows and at least one pattern-to-mask alignment mark etched into the mask substrate from the same side as the mask windows. The pattern-to-mask alignment marks can be etched at the same time as the mask windows and are detectable from the front surface of the mask substrate by an electron beam lithography system prior to creating the circuit pattern. The alignment marks are detected by the absence of backscattered electrons at the pattern-to-mask alignment marks.

Abstract: An improved structure for electron beam lithography grids and a method of fabricating such grids yields calibration grids having grid lines coplanar with the surface of the grid body and laterally supported by grooves formed in the grid body and which can also be cleaned after contamination by outgassing resist during use by virtue of the provision of such lateral support for the grid lines. The grid exhibits improved accuracy due to the technique of fabrication of the grooves. The invention thus allows the electron beam lithography process to be conducted with less expense and at greater speed. The improved accuracy of the calibration grid also permits integrated circuits and masks used in the fabrication of such devices to be designed more flexibly and fabricated at reduced cost and improved integration densities and manufacturing yields.

Abstract: An improved structure for electron beam lithography grids and a method of fabricating such grids yields calibration grids having grid lines coplanar with the surface of a the grid body and laterally supported by grooves formed in the grid body and which can also be cleaned after contamination by outgassing resist during use by virtue of the provision of such lateral support for the grid lines. The grid exhibits improved accuracy due to the technique of fabrication of the grooves. The invention thus allows the electron beam lithography process to be conducted with less expense and at a greater speed. The improved accuracy of the calibration grid also permits integrated circuits and masks used in the fabrication of such devices to be designed more flexibly and fabricated at reduced cost and improved integration densities and manufacturing yields.

Abstract: A three-stage E-beam deflection system employs breaking the entire field to be scanned into clusters and sub-fields. The scanning provided by the first stage of deflection which scans within the entire field is rectilinear and discontinuous with the scan stopping in the center of each of the clusters where an exposure is to be made, and scanning is the same within each cluster from sub-field to sub-field. The scanning within a cluster by the second stage stops in the center of each sub-field where exposure is to be made. The third stage uses high speed electrostatic deflection to provide scanning with a vector scanning mode within the sub-field being scanned.

Abstract: A two staqge, electron beam projection system includes a target, a source of an electron beam and means for projecting an electron beam towards the target with its upper surface defining a target plane. A magnetic projection lens has a principal plane and a back focal plane located between said means for projecting and the target. The means for projecting provides an electron beam directed towards the target. First stage means provides deflection of the beam from area to area within a field. Second stage means provides for deflection of the beam for providing deflection of the beam within an area within a field. The beam crossing the back focal plane produces a telecentric condition of the beam in the image plane with the beam substantially normal to the target plane from the principal plane to the target plane.

Abstract: An electrostatic deflection plate for charged particle beam systems is formed of a planar semiconductive substrate having a conductive region at the substrate surface. The conductive region is diffused or implanted into the body of the substrate, or one or more conductive layers are deposited upon the substrate surface. The substrate material is preferably silicon and the diffused or implanted region is formed of a nonmagnetic, nonoxidizable metal such as gold or platinum. The deposited conductive region may be formed of a single layer of these or similar metals, one or more conductive underlayers with a nonmagnetic, nonoxidizable overlayer, a single or multilayer structure with a conductive oxide on the outermost layer, or a metallo-organic compound which forms a conductive layer during following heat treatment. The deflection plates are fabricated using conventional semiconductor processes and form durable structures which minimize eddy current effects.

Abstract: A variable axis immersion lens electron beam projection system shifts the electron beam while eliminating rapidly changing fields, eddy currents and stray magnetic fields in the target area. The electron beam projection system includes an electron beam source and a deflection means. A variable axes immersion lens for focusing the electron beam includes an upper pole piece, and a lower pole piece having a non-zero bore section, a zero bore section and an opening therebetween for inserting the target into the lens. The variable axis immersion lens provides an axial magnetic projection field which has zero first derivative in the vicinity of the target area. A magnetic compensation yoke, positioned within the bore of the upper pole piece produces a magnetic compensation field which is proportional to the first derivative of the axial magnetic projection field.

Abstract: An electron beam projection system having a projection lens arranged so that upon pre-deflection of the electron beam the electron optical axis of the lens shifts to be coincident with the deflected beam. The projection system includes means for producing an electron beam, means for deflecting the beam, a magnetic projection lens having rotational symmetry for focusing the deflected beam and a pair of magnetic compensation yokes positioned within the bore of the projection lens means. The pair of correction yokes has coil dimensions such that, in combination, they produce a magnetic compensation field proportional to the first derivative of the axial magnetic field strength distribution curve of the projection lens. Upon application of current to the pair of compensation yokes the electron optical axis of the projection lens shifts to the position of the deflected beam so that the electron beam remains coincident with the shifted electron optical axis and lands perpendicular to a target.