Abstract: The specification describes a method and apparatus for electron beam lithography wherein a Wehnelt electron gun is modified to improve the uniformity of the electron beam. The bias on the Wehnelt aperture is reversed from the conventional bias so that it is biased positively with respect to the cathode. The Wehnelt opening is tapered with a disk emitter inserted into the taper. The result of these modifications is an electron beam output with low brightness which is highly uniform over the beam cross section.

Abstract: The specification describes a method and apparatus for electron beam lithography wherein a Wehnelt electron gun is modified to improve the uniformity of the electron beam. A mesh grid is applied to the Wehnelt aperture and the mesh grid functions as a multiple secondary emitter to produce a uniform beam flux over a wide area. The grid voltage of the modified gun is substantially lower than in a conventional Wehnelt gun, i.e. less than 100 volts, which can be switched conveniently and economically using semiconductor drive circuits.

Abstract: The specification describes a method and apparatus for electron beam lithography wherein a Wehnelt electron gun is modified to improve the uniformity of the electron beam. A mesh grid is applied to the Wehnelt aperture and the mesh grid functions as a multiple secondary emitter to produce a uniform beam flux over a wide area. The grid voltage of the modified gun is substantially lower than in a conventional Wehnelt gun, i.e. less than 100 volts, which can be switched conveniently and economically using semiconductor drive circuits.

Abstract: The specification describes a method and apparatus for electron beam lithography wherein a Wehnelt electron gun is modified to improve the uniformity of the electron beam. A mesh grid is applied to the Wehnelt aperture and the mesh grid functions as a multiple secondary emitter to produce a uniform beam flux over a wide area. The grid voltage of the modified gun is substantially lower than in a conventional Wehnelt gun, i.e. less than 100 volts, which can be switched conveniently and economically using semiconductor drive circuits.

Abstract: A lithographic process for device fabrication in which a pattern is transferred from a mask into an energy sensitive material by projecting charged particle (e.g. electron beam) radiation onto the mask is disclosed. The pattern on the mask is divided into segments. The radiation transmitted through the mask and incident on the layer of energy sensitive material transfers a continuous image of the segmented mask pattern into the energy sensitive material. The images of each segment are joined together to form the continuous image by seam blending techniques. The seam blending techniques employ duplicate pattern information on segments for which the images are joined together. The image of the duplicate pattern information from a first segment is overlapped with the image of the duplicate pattern information from the second segment to blend the seams together.

Abstract: The invention provides an improved process for fabricating masks suitable for use in SCALPEL and similar electron-based or ion-based lithographic processes. Specifically, the process allows use of commercially-available (100) oriented silicon substrates, and better control over the profiles of mask struts. Specifically, the struts of the mask are formed by plasma etching, using a fluorine-based gas, and a unique multilayer mask blank is fabricated to promote successful use of the plasma etch. According to an embodiment of the process, an etch stop layer is deposited onto the front surface of a silicon substrate, and a membrane layer is deposited over the etch stop layer. A scattering layer, typically tungsten, is deposited over the membrane layer. A patterning layer is deposited on the back surface of the substrate, and the desired grillage pattern for the struts is patterned into the patterning layer.

Abstract: An improved, scattering-type mask for use in a charged-particle beam lithography process comprises the mask having a membrane portion and a scattering portion, the membrane portion being fabricated with a conductive material or a plurality of materials in which one of them is conductive. The conductive nature of the membrane portion mitigates the accumulation of charge in the mask, thereby enhancing the definition of the charged-particle pattern transferred from the mask onto the wafer under fabrication and reducing the distortion obtained with the system.

Abstract: The invention is directed to a method and apparatus of projection lithography in which the contrast introduced into a radiation sensitive material caused by the proximity effect is effectively removed in a single exposure. Patterned radiation is transmitted through a lens system with at least one lens and a back focal plane filter. The back focal plane filter has at least two apertures, an image aperture and a proximity effect correction aperture. Patterned radiation is transmitted through the image aperture and introduces the desired image into the energy sensitive resist material. A portion of the inverse pattern radiation is transmitted through the proximity effect correction aperture and onto the energy sensitive resist material to effectively remove the contrast therein caused by the proximity effect.