Micro-objective lens with compact secondary electron detector for miniature low voltage electron beam systems

1996 ◽  
Vol 14 (6) ◽  
pp. 3738 ◽  
Author(s):  
W. Liu
Keyword(s):  
Electron Beam ◽  
Secondary Electron ◽  
Low Voltage ◽  
Objective Lens ◽  
Electron Detector ◽  
Voltage Electron

Ultra-high resolution SEMI-in-lens type FE-SEM, JSM-6320F, with strong magnetic-field lens with built-in secondary-electron detector

1994 ◽  
Vol 52 ◽  
pp. 484-485
Author(s):  
T. Miyokawa ◽  
H. Kazumori ◽  
S. Nakagawa ◽  
C. Nielsen
Keyword(s):  
High Resolution ◽  
Secondary Electron ◽  
Spherical Aberration ◽  
Incident Beam ◽  
Chromatic Aberration ◽  
Magnetic Flux Density ◽  
Objective Lens ◽  
Electron Detector ◽  
High Resolution Images ◽  
Working Distance

We have developed a strongly excited objective lens with a built-in secondary electron detector to provide ultra-high resolution images with high quality at low to medium accelerating voltages. The JSM-6320F is a scanning electron microscope (FE-SEM) equipped with this lens and an incident beam divergence angle control lens (ACL).The objective lens is so strongly excited as to have peak axial Magnetic flux density near the specimen surface (Fig. 1). Since the speciien is located below the objective lens, a large speciien can be accomodated. The working distance (WD) with respect to the accelerating voltage is limited due to the magnetic saturation of the lens (Fig.2). The aberrations of this lens are much smaller than those of a conventional one. The spherical aberration coefficient (Cs) is approximately 1/20 and the chromatic aberration coefficient (Cc) is 1/10. for accelerating voltages below 5kV. At the medium range of accelerating voltages (5∼15kV). Cs is 1/10 and Cc is 1/7. Typical values are Cs-1.lmm. Cc=l. 5mm at WD=2mm. and Cs=3.lmm. Cc=2.9 mm at WD=5mm. This makes the lens ideal for taking ultra-high resolution images at low to medium accelerating voltages.

Promising Zn3Ta2O8:Pr3+ Red Phosphor for Low Voltage Cathodoluminescence Applications

2011 ◽  
Vol 306-307 ◽  
pp. 251-254 ◽  
Author(s):  
Shreyas S. Pitale ◽  
L.L. Noto ◽  
I.M. Nagpure ◽  
O.M. Ntwaeaborwa ◽  
J.J. Terblans ◽  
...  
Keyword(s):  
Electron Beam ◽  
Photoelectron Spectroscopy ◽  
Low Voltage ◽  
Chemical Constituents ◽  
High Energy ◽  
Binding Energies ◽  
Xenon Lamp ◽  
Voltage Electron ◽  
Information Displays ◽  
Prime Concern

Zn3Ta2O8 is a promising host for low voltage cathodoluminescence (CL) applications. Surface chemical stability during low voltage electron beam excitation is a prime concern for phosphors to be used in various new generation information displays. Photoluminescence (PL) and CL characteristics of the Zn3Ta2O8 host doped with Pr3+ are presented. The phosphors were synthesized via solid-state reaction route at 1100°C. Red CL or PL with a maximum at 611 nm, attributed to the 1D2-3H4 transition of the Pr3+ ion, was observed at room temperature under high energy electron (2 keV, 12 μA) or a monochromatic xenon lamp (257 nm) irradiation. Electron stimulated chemical changes on the surface of the Zn3Ta2O8:Pr3+ phosphor during an electron beam exposure from 0-350 C/cm2 was monitored using Auger electron spectroscopy. The CL exhibited only a 20% loss in the original intensity during the continuous electron beam exposure. X-ray photoelectron spectroscopy (XPS) was used to estimate the redox states of the chemical constituents and a comparison of binding energies was made with the standard Ta2O5 and ZnO compounds. A correlation between the structural configuration of Zn3Ta2O8 and the XPS data is also established.

Low voltage electron beam lithography in self‐assembled ultrathin films with the scanning tunneling microscope

1994 ◽  
Vol 64 (3) ◽  
pp. 390-392 ◽  
Author(s):  
C. R. K. Marrian ◽  
F. K. Perkins ◽  
S. L. Brandow ◽  
T. S. Koloski ◽  
E. A. Dobisz ◽  
...  
Keyword(s):  
Electron Beam ◽  
Ultrathin Films ◽  
Electron Beam Lithography ◽  
Scanning Tunneling Microscope ◽  
Low Voltage ◽  
Scanning Tunneling ◽  
Tunneling Microscope ◽  
Voltage Electron ◽  
Self Assembled

Electrostatic Aberration Correction in LV-SEM

2000 ◽  
Vol 6 (S2) ◽  
pp. 746-747 ◽  
Author(s):  
D.J. Maas ◽  
A. Henstra ◽  
M.P.C.M. Krijn ◽  
S.A.M. Mentink
Keyword(s):  
Electron Microscope ◽  
Low Voltage ◽  
State Of The Art ◽  
Spherical Aberration ◽  
Positive Definite ◽  
Ease Of Use ◽  
Objective Lens ◽  
Time Varying ◽  
Voltage Electron ◽  
Aberration Corrected

The resolution of a low-voltage electron microscope is limited by the chromatic and spherical aberration of the objective lens, see Fig. 1. The design of state-of-the-art objective lenses is optimised for minimal aberrations. Any significant improvement of the resolution requires an aberration corrector. Recently, correction of both Cc and Cs has been demonstrated in SEM, using a combination of magnetic and electrostatic quadrupoles and octupoles (Zach and Haider, 1995). The present paper presents an alternative design, which is based on a purely electrostatic concept, potentially simplifying the ease-of-use of an aberration corrected microscope.In 1936 Scherzer showed that the fundamental lens aberrations of round lenses are positive definite, in absence of time-varying fields and/or space charge. Negative lens aberrations, required for the correction of Cc and Cs, can only be obtained using non-round lenses, e.g. quadrupoles and octupoles (Scherzer, 1947).

Current and future aberration correctors for the improvement of resolution in electron microscopy

2009 ◽  
Vol 367 (1903) ◽  
pp. 3665-3682 ◽  
Author(s):  
M. Haider ◽  
P. Hartel ◽  
H. Müller ◽  
S. Uhlemann ◽  
J. Zach
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Low Voltage ◽  
Spherical Aberration ◽  
Chromatic Aberration ◽  
Objective Lens ◽  
Voltage Electron ◽  
System A ◽  
Transmission Electron ◽  
Correction System

The achievable resolution of a modern transmission electron microscope (TEM) is mainly limited by the inherent aberrations of the objective lens. Hence, one major goal over the past decade has been the development of aberration correctors to compensate the spherical aberration. Such a correction system is now available and it is possible to improve the resolution with this corrector. When high resolution in a TEM is required, one important parameter, the field of view, also has to be considered. In addition, especially for the large cameras now available, the compensation of off-axial aberrations is also an important task. A correction system to compensate the spherical aberration and the off-axial coma is under development. The next step to follow towards ultra-high resolution will be a correction system to compensate the chromatic aberration. With such a correction system, a new area will be opened for applications for which the chromatic aberration defines the achievable resolution, even if the spherical aberration is corrected. This is the case, for example, for low-voltage electron microscopy (EM) for the investigation of beam-sensitive materials, for dynamic EM or for in-situ EM.

Energy Transfer and Tunable Luminescence of NaLa(PO3)4:Tb3+/Eu3+ under VUV and Low-Voltage Electron Beam Excitation

2014 ◽  
Vol 118 (6) ◽  
pp. 3220-3229 ◽  
Author(s):  
Chunmeng Liu ◽  
Dejian Hou ◽  
Jing Yan ◽  
Lei Zhou ◽  
Xiaojun Kuang ◽  
...  
Keyword(s):  
Electron Beam ◽  
Energy Transfer ◽  
Low Voltage ◽  
Voltage Electron ◽  
Electron Beam Excitation ◽  
Beam Excitation
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