THE HEBREW UNIVERSITY CENTER FOR NANOSCIENCE AND NANOTECHNOLOGY

Raith e_LiNE - e-Beam Lithography System


An ultra High Resolution Electron Beam Lithography system and nanoengineering workstation for universities and other academic institutions. Selected options for nanomanipulation, EBID and EBIE expand this system to a versatile nano-engineering workstation. The state-of-the-art e_LiNE electron column matches perfectly with a number of key applications in CNT research, thin film engineering, photonic crystals and EBID.

Key applications:
Lithography on 4 inch samples
EBID and EBIE
In-situ electrical measurements and nanomanipulation, e.g. CNT or nanorods

Basic hardware features:
Thermal assisted field emission gun.
Cross-over free column with highest beam current density at 2 nm spot size.
Laser interferometer stage with 100 mm by 100 mm travel range and 2 nm resolution achieved by closed-loop piezo-positioning.
10 MHZ DSP-controlled digital pattern generator.
Gas injection system, nanomanipulators, loadlock.
e_LiNE specifications:
Minimum line width < 20 nm
Stitching accuracy 40 nm
Overlay accuracy 40 nm

Nanomanipulators:
Nanomanipulators are used for making electrical contact to nano structures. They also serve for mechanical probing of nano structures. The nanomanipulators are mounted inside the chamber and are not connected to the stage - thus allowing access to any position even on very large samples.

Stitching:
Limited electron beam scan deflection range is overcome by combination of stage movement and e-beam scanning. Large pattern of mm or cm size are divided into smaller fields, typically of 50, 100 or 200 µm and exposed in serial mode to reconstruct the original sized pattern. This is called stitching. Stage movement is 50, 100 or 200 µm to adjacent field. The remaining error along the small field borders due to stage positioning and distortion of beam deflection is called stitching error.

EBID - Electron Beam Induced Deposition:
Precursors heated above vapor pressure are delivered by a gas injector unit close to the sample surface. The electron beam cracks the gas molecules into volatile and deposit. Various precursors can be used for different deposit composition: e.g. Tungsten, Platinum, Si0x and Gold.

EBIE - Electron Beam Induced Etching
Material can be removed by a controlled gas flow near the point of electron penetration into the substrate.

CNT
carbon nanotubes