Page 36 - Principles and Applications of NanoMEMS Physics

22 Chapter 1

1.2.3 Nanoetechnology Fabrication Elements

The elements of nanotechnology fabrication range from techniques to
produce two-dimensional patterns with deep-submicron/nanometer-scale
widths, to techniques to produce atomic-thick layers/multi-layers of various
material compositions, to techniques to precisely manipulate atomic-size
particles. These techniques, together with those presented previously,
constitute the arsenal at the core of NanoMEMS.

1.2.3.1 Electron Beam Lithography

Electron beam lithography utilizes electrons, instead of the projection of a
mask image illuminated by photons, to create directly the desired pattern on
the PR, Figure 1-19.

Electron Gun
Electron Gun
X-Y Mask
X-Y Mask
Data Beam Blanking
Data
Beam Blanking
Deflection Coils
Deflection Coils
Computer
Computer
Vacuum Chamber
Vacuum Chamber
Control
Control
Electron Resist
Electron Resist
Metal Film
Metal Film
e e - -
Substrate
Substrate
Table
Table
Table
Table
Mechanical
Mechanical
Position
Position
Drive
Drive
Monitor
Monitor
Figure 1-19. Sketch of electron bean lithography system. (After [23].)
Since the wavelength of electron accelerated through a potential difference
V is (λ Å) = 150 V , an electron beam may be focused to a diameter of
. 0 01− 5 . 0 µ m, and resolutions of 1nm are obtained. The electron beam is
focused and scanned either in a raster (sequential) fashion, or in a vector
fashion where the image field consists of independently
addressable/exposable pixels, Fig. 1-20.