Development of a four-element conical electron lens dedicated to high resolution Auger electron-ion(s) coincidence experiments Rev. Sci. Instrum. 73, 3885 (2002); 10.1063/1.1511799Variable axis lens of mixed electrostatic and magnetic fields and its application in electron-beam lithography systems J.The emittance required for the SCALPEL system is very large; on the order of 2 mm mrad. This can be achieved with an electron source using advanced, large area cathodes and complicated extraction optics, but in this article an alternative approach is presented: devices which increase the effective emittance of an electron beam by creating an array of subbeams. After we have explained the theory, we discuss three different configurations which form electrostatic microlens array-like fields, and we show results from computer modeling.

Electron detection characteristics such as modulation transfer function (MTF), detection quantum efficiency (DQE), dynamic range, linearity, average gain, and uniformity of a high-voltage multiscan CCD (HV-MSC, 1K x 1K pixels) camera were evaluated. This camera was used as a major recording medium in a high-voltage electron microscope (HVEM) installed at the Korea Basic Science Institute (KBSI). In spite of the high energy of the incident electrons, the overall properties of the HV-MSC camera were comparable to other CCD cameras for a low-voltage electron microscope (LVEM). In order to take full advantages of the properties of the HV-MSC camera for atomic resolution electron microscopy, we discuss optimal experimental conditions based on the detection properties.

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The commercial applicability of electron beam projection lithography systems may be limited at high resolution because of low throughput. The main limitations to the throughput are:• Beam current. The Coulomb interaction between electrons result in an image blur. Therefore less beam current can be allowed at higher resolution, impacting the illumination time of the wafer. • Exposure field size. Early attempts to improve throughput with "full chip" electron beam projection systems failed, because the systems suffered from large off-axis aberrations of the electron optics, which severely restricted the useful field size. This has impact on the overhead time.A new type of projection optics will be proposed in this paper to overcome both limits. A slider lens is proposed that allows an effective field that is much larger than schemes proposed by SCALPEL and PREVAIL. The full width of the die can be exposed without mechanical scanning by sliding the beam through the slit-like bore of the lens. Locally, at the beam position, a "round"-lens field is created with a combination of a rectangular magnetic field and quadrupoles that are positioned inside the lens. A die can now be exposed during a single mechanical scan as in state-of-the-art light optical tools.The total beam current can be improved without impact on the Coulomb interaction blur by combining several beams in a single lithography system if these beams do not interfere with each other. Several optical layouts have been proposed that combine up to 5 beams in a projection system consisting of a doublet of slider lenses. This type of projection optics has a potential throughput of 50 WPH (300 mm) at 45 nm with a resist sensitivity of 6 µC/cm 2 .