Scanning Electron Microscopy and X-Ray Microanalysis

VIII

threshold. This threshold can only be lowered

by increasing beam current, pixel dwell time,

and/or detector efficiency. Selecting higher

beam current means a larger beam size, caus-

ing resolution to deteriorate. Thus, there is a

dynamic contest between resolution and visibil-

ity leading to inevitable limitations on feature

size and feature visibility that can be achieved.

3. The beam divergence angle can be minimized
   to increase the depth-of-field (e.g.,. Fig.  3 ).
   With optimized selection of aperture size and
   specimen-to-objective lens distance (work-
   ing distance), it is generally possible to achieve
   small beam convergence angles and therefore
   effective focus along the beam axis that is at
   least equal to the horizontal width of the image.

a

c

b

d

100 nm YK EHT - 15.00 kV

WD - 1.7 mm Signal A = InlLensI Probe - 135 pAESB Grid = 800 VImage Pixel Size - 1.184 nm

HV 100 000 xmag HFW WD 500 nmHelios

200nm

100nm

x500,000 0.30kV UED GBSH10nmWD 2.0mmJEOL

SU8200 0.50kV-D 1.6mm X 200k SE+BSE(TU)

SU8200 0.50kV-D 1.6mm X 500k SE+BSE(TU)

800.00 V 1.49 μm990.7 μm

Signal B = InlLens Mag - 94.28 K XWidth - 1.213 mm Date: 19 Oct 2015

. Fig. 1 a High resolution SEM image taken at high
beam energy (E 0 = 15 keV) of a finFET transistor (16-nm
technology) using an in-lens secondary electron detector.
This cross section was prepared by inverted Ga FIB milling
from backside (Zeiss Auriga Cross beam; image courtesy
of John Notte, Carl Zeiss); Bar = 100 nm. b High resolu-
tion SEM image taken at low beam energy (E 0 = 0.8 keV) of
zeolite (uncoated) using a through-the-lens SE detector

(image courtesy of Trevan Landin, FEI); Bar = 500 nm. c

Mesoporous silica nanosphere showing 5-nm-diameter

pores imaged with a landing energy of 0.5 keV (specimen

courtesy of T. Yokoi, Tokyo Institute of Technology; images

courtesy of A. Muto, Hitachi High Technologies); Upper image

Bar = 200 nm, Lower image Bar = 100 nm. d Si nanoparticle

imaged with a landing energy of 0.3 keV; Bar = 10 nm

(image courtesy V. Robertson, JEOL)

Scanning Electron Microscopy and Associated Techniques: Overview