The fabrication of a microcircuit by beam lithography requires an economic distribution of processing time between the high resolution portions of the exposure pattern and areas of much lower resolution. At least one ion beam provides the high resolution performance and at least one electron beam satisfies the lower resolution requirement. The beams are independently operable and are relatively inclined for substantial convergence at the substrate. The convergence is such that all beams can be scanned simultaneously in a single elemental area of substrate or in adjacent elemental areas which are presented for exposure in sequence. For registration the substrate is imaged by electron scanning and the positions of registration marks are related in the image to predetermined positions which represent the required position of the substrate. A positional correction signal is derived by observation of image brightness, size and orientation at the predetermined positions. The signal is processed by a computer which holds all positional control and scan control data and instructs the relevant controls.
Methods and devices are disclosed for controlling blur resulting from the space-charge effect and geometrical aberration in a charged-particle-beam microlithography apparatus. Based on the pattern-element densities of the exposure units to be transferred to the substrate, a relationship between the total blur and the beam semi-angle, the current density, and/or the beam-acceleration voltage is determined. An optimal beam semi-angle, current density, and/or beam-acceleration voltage is calculated to: (1) minimize the blur during the transfer-exposure of an exposure unit having a certain pattern-element density; (2) make the blur constant during the transfer-exposure of a group of exposure units having various pattern-element densities; or (3) maximize the patterned-beam current during the transfer-exposure of an exposure unit having a certain pattern-element density and blur tolerance. The beam semi-angle, current density, and/or acceleration voltage of the CPB-optical system is then adjusted to the calculated value.
A linear semiconductor material having a thin metal-oxide layer and a resist layer is conveyed at a constant speed by rotating rollers. An electron-beam drawing apparatus, in which micro-electron-guns are aligned circumferentially, is disposed between the rollers. The linear semiconductor material passes through a cylindrical hole of the electron-beam drawing apparatus such that a circuit pattern is formed on a surface of the linear semiconductor material by an electron beam. The linear semiconductor material is developed and etched, and divided into predetermined lengths. Thus a linear semiconductor is completed. A semiconductor device is manufactured by bundling a plurality of the linear semiconductors of predetermined length.
Disclosed are a scanning electron microscope for cross section observation capable of cutting more accurately a cross section of a specific portion of semiconductor wafer in a shorter time, and a cross section observing method employing such a microscope. The scanning electron microscope includes an SEM column 100, an FIB column 200 mounted together with SEM column 100, and a reflected-electron detector 21 for detecting electrons to be reflected from the semiconductor wafer by scanning with an electron beam 30 from the SEM. Thus, since a process of cutting a cross section to be observed by scanning with an ion beam 31 from FIB column 200 can be observed in real time by employing the reflected electrons of electron beam 30 from SEM column 100, a specific portion of the cross section can be cut more accurately in a shorter time.
An apparatus for effecting preparation and observation of a topographic section in a particular region of a sample. The apparatus includes: a sample chamber for containing a sample, an ion beam irradiation unit mounted in the sample chamber for irradiating the sample with a scanned ion beam to groove the particular region to thereby prepare the topographic section, an electron beam irradiation unit mounted in the sample chamber for irradiating the topographic section with a scanned electron beam, the electron beam irradiation unit being arranged relative to the ion beam irradiation unit such that the electron beam intersects the ion beam at the particular region at an angle not exceeding 90.degree., a detector for detecting secondary electrons released from the sample upon irradiation with the ion beam and the electron beam, a beam switching circuit operable during the course of the preparation of the topographic section for temporarily switching from the ion beam to the electron beam, and a display connected to the detector and operative in response to the switching for displaying an image of the topographic section based on the detection of the secondary electrons released by the irradiation with the electron beam to thereby temporarily observe the topographic section during the course of the preparation thereof.
A charged particle beam apparatus comprising a charged particle beam source(s) for generating an ion beam and an electron beam, a focusing lens system for finely focusing each of the generated ion beam and electron beam, a charged particle beam deflecting system for deflecting each of the focused ion beam and electron beam, and a specimen subjected to irradiation thereof with each of the focused ion beam and electron beam is provided with means for detecting the deviation of the irradiation positions of the ion beam and the electron beam on the specimen from each other and means for making the irradiation positions of the ion beam and the electron beam on the specimen coincident with each other on the basis of the result of detection of the deviation of the irradiation positions from each other.
