Electron-beam lithography

About: Electron-beam lithography is a research topic. Over the lifetime, 8982 publications have been published within this topic receiving 143325 citations. The topic is also known as: e-beam lithography.

Lithographic approach for 100 nm fabrication by focused ion beam

Abstract: A bilevel resist process using P(SiSt90–CMS10) silicon containing resist as a top layer has been developed for Ga+ focused ion beam (FIB) lithography. A 100 nm linewidth pattern with 750 nm thickness has been demonstrated. Lithographic characteristics for 100 kV Ga+ FIB have been studied for PMMA positive resist and P(SiSt90–CMS10) negative resist. The results indicate that backscattering and proximity effects are negligible and that 100 kV Ga+ FIB resist sensitivity is about 100 times larger than that for 20 kV electron beam. Moreover, it has been observed that discontinuous lines, which may be caused by shot noise or by an oscillation at the end of the Taylor cone of Ga ion source, are produced at low dose for both PMMA and P(SiSt90–CMS10) resists.

A hybrid approach to nanoelectronics

Abstract: The definition of features on the nanometre length scale (NLS) is impossible via conventional lithography, but can be done using extreme ultraviolet, synchrotron-radiation, or electron beam lithography. However, since these techniques are very expensive and still in their infancy, their exploitation in integrated circuit (IC) processing is still highly putative. Geometries on the NLS can however be produced with relative ease using the spacer patterning technique, i.e. transforming vertical features (like film thickness) in the vicinity of a step of a sacrificial layer into horizontal features. The ultimate length that can be produced in this way is controlled by the steepness of the step defining the sacrificial layer, the uniformity of the deposited or grown films, and the anisotropy of its etching. While useful for the preparation of a few devices with special needs, the above trick does not allow by itself the development of a nanotechnology where each layer useful for defining the circuit should be on the NLS and aligned on the underlying geometries with tolerances on the NLS. Setting up such a nanotechnology is a major problem which will involve the IC industry in the post-Roadmap era. Irrespective of the detailed structure of the basic constituents (molecules, supramolecular structures, clusters, etc), ICs with nanoscopic active elements can hardly be prepared without the ability to produce arrays of conductive strips with pitch on the NLS. This work is devoted to describing a scheme (essentially based on the existing microelectronic technology) for their production without the use of advanced lithography and how it can be arranged to host molecular devices.

Microfabrication below 10 nm

Abstract: We describe a new method of producing ultrasmall structures on thick substrates with electron beam lithography. Using an innovative exposure technique, we obtain features with lateral sizes smaller than the incident beam diameter. These patterns are transferred into GaAs/AlGaAs quantum well heterostructures using chemically assisted ion beam etching, and uniform arrays of structures with lateral dimensions below 10 nm are produced. We employ reflection electron microscopy measurements to correlate the structure size with the exposure and development conditions for this fabrication scheme.

Distributed, multiple variable shaped electron beam column for high throughput maskless lithography

Abstract: The ultimate resolution obtainable with focused electron beams is, for practical purposes in lithography, unlimited. Existing e-beam lithography systems are too slow to be practical for high volume manufacturing of semiconductor devices, however. The usable current in probe forming systems is limited by the stochastic Coulomb interaction in the beam path, which causes loss of resolution at high current. This is due to the need to pass all of the writing current through an aperture. Distributed systems, by contrast, do not suffer from this problem, as the current is spread over a large volume. The purpose of this article is to propose a distributed system, employing multiple, variable shaped beams for direct write (maskless) lithography. We call this system DiVa, to emphasize the key attributes of distributed writing current, and variable beam shaping. It utilizes a planar cathode, patterned with a rectilinear array of square emitters. Focusing is accomplished by a uniform, axial magnetic field, oriented a...