The present invention provides an electron beam apparatus for irradiating a sample with primary electron beams to detect secondary electron beams generated from a surface of the sample by the irradiation for evaluating the sample surface. In the electron beam apparatus, an electron gun has a cathode for emitting primary electron beams. The cathode includes a plurality of emitters for emitting primary electron beams, arranged apart from one another on a circle centered at an optical axis of a primary electro-optical system. The plurality of emitters are arranged such that when the plurality of emitters are projected onto a straight line parallel with a direction in which the primary electron beams are scanned, resulting points on the straight line are spaced at equal intervals.

Electron beam apparatus and method of manufacturing semiconductor device using the apparatus

A method and apparatus for inspecting pattern defects emitting a laser beam, adjusting a light-amount of the laser beam, converting the light-amount adjusted laser beam into a slit-like laser light flux, lowering coherency of the slit-like laser light flux, and irradiating a sample with the coherence reduced slit-like laser light flux. An image of reflection light from the sample is obtained, and a detector is provided which includes the image sensor for receiving the image of the reflection light and for converting it into a detected image signal. An image processor is provided for detecting defects on patterns formed on the sample in accordance with the detected image signal.

Method and apparatus for inspecting pattern defects

A charged particle beam apparatus is provided which comprises a charged particle source (1) for producing a primary beam of charged particles, aperture means (2) for collimating said primary beam of charged particles, wherein said aperture means is adapted to switch between a collimation of said primary beam to a width appropriate for serial imaging of a sample (8) as well as a collimation of said primary beam to a width appropriate for parallel imaging of said sample (8), a condenser lens (3) for condensing said primary beam of charged particles, scanning means (5) for deflecting said primary beam of charged particles, an objective lens (6) for focusing said condensed primary beam, a sectorized detector (7) for detecting a secondary charged particles. Also, several different operation modes of the beam apparatus are described allowing for serial imaging as well as parallel imaging.

Charged particle beam apparatus and method for operating the same

A multi-column electron beam inspection system is disclosed herein. The system is designed for electron beam inspection of semiconductor wafers with throughput high enough for in-line use. The system includes field emission electron sources, electrostatic electron optical columns, a wafer stage with six degrees of freedom of movement, and image storage and processing systems capable of handling multiple simultaneous image data streams. Each electron optical column is enhanced with an electron gun with redundant field emission sources, a voltage contrast plate to allow voltage contrast imaging of wafers, and an electron optical design for high efficiency secondary electron collection.

Multi-beam multi-column electron beam inspection system

The invention relates to a charged particle multi-beamlet system for exposing a target (11) using a plurality of beamlets (21). The system has a charged particle source (1), an aperture array (4), a beamlet manipulator, a beamlet blanker (6), and an array of projection lens systems. The charged particle source (1) is configured to generate a charged particle beam (20). The aperture array (4) is configured to define separate beamlets (21) from the generated beam. The beamlet manipulator is configured to converge groups of the beamlets towards a common point of convergence for each group. The beamlet blanker (6) is configured to controllably blank beamlets in the groups of beamlets. Finally, the array of projection lens systems (10) is configured to project unblanked beamlets of the groups of beamlets on to the surface of the target (11). The beamlet manipulator is further adapted to converge each of the groups of beamlets towards a point corresponding to one of the projection lens systems.

Projection lens arrangement

Electron beam lithography systems have historically had low throughput. The only practical solution to this limitation is an approach using many beams writing simultaneously. For single-column multi-beam systems, including projection optics (SCALPELR and PREVAIL) and blanked aperture arrays, throughput and resolution are limited by space-charge effects. Multibeam micro-column (one beam per column) systems are limited by the need for low voltage operation, electrical connection density and fabrication complexities. In this paper, we discuss a new multi-beam concept employing multiple columns each with multiple beams to generate a very large total number of parallel writing beams. This overcomes the limitations of space-charge interactions and low voltage operation. We also discuss a rationale leading to the optimum number of columns and beams per column. Using this approach we show how production throughputs >= 60 wafers per hour can be achieved at CDs <EQ 100 nm, independent of both wafer diameter and die size. The Cost-of-Ownership (CoO) advantages of direct-write (maskless) lithography are significant especially for small-volume semiconductor fabrication, for example ASICs, SOCs and MPUs.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

High-throughput NGL electron-beam direct-write lithography system

A multi-column charged particle optics assembly comprises: a first optical component which is continuous through all columns of the charged particle optics assembly; and a multiplicity of independently alignable second optical components coupled to the first optical component, such that there is one second component for each column in the charged particles optics assembly. The first component provides mechanical integrity to the charged particle optics assembly and each second optical component is independently alignable to the optic axis of its corresponding column. In a further embodiment, the charged particle optics assembly comprises: first and second continuous optical components; and a multiplicity of independently alignable electrodes coupled to the second optical component, such that there is a corresponding independently alignable electrode for each column.

Multi-column charged particle optics assembly

An electron beam column incorporating an asymmetrical detector optics assembly provides improved secondary electron collection. The electron beam column comprises an electron gun, an accelerating region, scanning deflectors, focusing lenses, secondary electron detectors and an asymmetrical detector optics assembly. The detector optics assembly comprises a field-free tube, asymmetrical with respect to the electron optical axis; the asymmetry can be introduced by offsetting the field-free tube from the electron optical axis or by chamfering the end of the tube. In other embodiments the detector optics assembly comprises a field-free tube and a voltage contrast plate, either or both of which are asymmetrical with respect to the electron optical axis.

Detector optics for electron beam inspection system

An image processing system for use in semiconductor wafer inspection comprises a multiplicity of self-contained image processors for independently performing image cross-correlation and defect detection. The system may also comprise an image normalization engine for performing image brightness and contrast normalization. The self-contained image processors and image normalization engine access image data from a memory array; the array is fed data from a multiplicity of imaging modules operating in parallel. The memory array is configured to allow simultaneous access for data input, normalization, and cross-correlation and defect detection. Multiple image processing systems can be configured in parallel as a single image processing computer, all sending defect data to a common display module.

N. William Parker

Papers

Multi-beam multi-column electron beam inspection system

High-throughput NGL electron-beam direct-write lithography system

Multi-column charged particle optics assembly

Detector optics for electron beam inspection system

Image processing system for multi-beam inspection