Probe design optimization for a high‐resolution scattering‐type scanning near‐field optical microscope

We present a probe of scanning near-field optical microscope (SNOM) with large aperture and high resolution, which is added a metallic dipole nano-antenna onto the tip of the ordinary probe. Based on the FDTD algorithm we investigate numerically the measure results by different aperture probes for the same sample with the incident wavelength of 830nm and the scan height of 10nm. The results show that the resolution of the new probe is 100nm, 75nm, 50 nm, 45 nm, 50 nm, 70nm when the probe aperture is 50nm, 100nm, 130nm, 150nm, 170nm, 200nm respectively, and for the ordinary probe the resolution is 50nm，120 nm,140 nm,180 nm, 200nm, 220nm correspondingly. That is to say the resolution of the ordinary probe decrease rapidly with the increasing of the aperture, however the novel probe can maintain the high resolution.

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High resolution and high sensitivity near-field optical microscope

Microelectronic Engineering ◽

10.1016/s0167-9317(00)00398-1 ◽

2000 ◽

Vol 53 (1-4) ◽

pp. 653-656 ◽

Cited By ~ 3

Author(s):

J.M. Freyland ◽

R. Eckert ◽

H. Heinzelmann

Keyword(s):

High Resolution ◽

Near Field ◽

High Sensitivity ◽

Optical Microscope

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Method to produce high-resolution scanning near-field optical microscope probes by beveling optical fibers

Review of Scientific Instruments ◽

10.1063/1.1304866 ◽

2000 ◽

Vol 71 (8) ◽

pp. 3118-3122 ◽

Cited By ~ 30

Author(s):

T. Held ◽

S. Emonin ◽

O. Marti ◽

O. Hollricher

Keyword(s):

High Resolution ◽

Optical Fibers ◽

Near Field ◽

Optical Microscope

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Near-field scanning optical microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100144644 ◽

1986 ◽

Vol 44 ◽

pp. 642-643

Author(s):

E. Betzig ◽

A. Harootunian ◽

M. Isaacson ◽

A. Lewis

Keyword(s):

Near Field ◽

Optical Microscope ◽

Visible Radiation ◽

Field Methods ◽

Optical Elements ◽

Optical Region ◽

Order Of Magnitude ◽

Nondestructive Imaging ◽

Scanning Optical Microscopy ◽

Near Field Scanning

In general, conventional methods of optical imaging are limited in spatial resolution by either the wavelength of the radiation used or by the aberrations of the optical elements. This is true whether one uses a scanning probe or a fixed beam method. The reason for the wavelength limit of resolution is due to the far field methods of producing or detecting the radiation. If one resorts to restricting our probes to the near field optical region, then the possibility exists of obtaining spatial resolutions more than an order of magnitude smaller than the optical wavelength of the radiation used. In this paper, we will describe the principles underlying such "near field" imaging and present some preliminary results from a near field scanning optical microscope (NS0M) that uses visible radiation and is capable of resolutions comparable to an SEM. The advantage of such a technique is the possibility of completely nondestructive imaging in air at spatial resolutions of about 50nm.

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Cosmetology treatments on human hair: An SEM study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100167160 ◽

1996 ◽

Vol 54 ◽

pp. 940-941

Author(s):

D.F. Bowling

Keyword(s):

High School ◽

High Resolution ◽

Human Hair ◽

Optical Microscope ◽

Convincing Evidence ◽

Brightness Contrast ◽

Sem Study

High school cosmetology students study the methods and effects of various human hair treatments, including permanents, straightening, conditioning, coloring and cutting. Although they are provided with textbook examples of overtreatment and numerous hair disorders and diseases, a view of an individual hair at the high resolution offered by an SEM provides convincing evidence of the hair‘s altered structure. Magnifications up to 2000X provide dramatic differences in perspective. A good quality classroom optical microscope can be very informative at lower resolutions.Students in a cosmetology class are initially split into two groups. One group is taught basic controls on the SEM (focus, magnification, brightness, contrast, specimen X, Y, and Z axis movements). A healthy, untreated piece of hair is initially examined on the SEM The second group cements a piece of their own hair on a stub. The samples are dryed quickly using heat or vacuum while the groups trade places and activities.

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New form of Transmission Cross Coefficient for High-Resolution Imaging

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100179051 ◽

1990 ◽

Vol 48 (1) ◽

pp. 60-61

Author(s):

Kazuo Ishizuka

Keyword(s):

Electron Microscope ◽

High Resolution ◽

Transmission Function ◽

Incident Beam ◽

Optical Microscope ◽

Strong Interactions ◽

Small Range ◽

Specimen Thickness ◽

Beam Direction ◽

Diffracted Waves

It is well known that taking into account spacial and temporal coherency of illumination as well as the wave aberration is important to interpret an image of a high-resolution electron microscope (HREM). This occues, because coherency of incident electrons restricts transmission of image information. Due to its large spherical and chromatic aberrations, the electron microscope requires higher coherency than the optical microscope. On an application of HREM for a strong scattering object, we have to estimate the contribution of the interference between the diffracted waves on an image formation. The contribution of each pair of diffracted waves may be properly represented by the transmission cross coefficients (TCC) between these waves. In this report, we will show an improved form of the TCC including second order derivatives, and compare it with the first order TCC.In the electron microscope the specimen is illuminated by quasi monochromatic electrons having a small range of illumination directions. Thus, the image intensity for each energy and each incident direction should be summed to give an intensity to be observed. However, this is a time consuming process, if the ranges of incident energy and/or illumination direction are large. To avoid this difficulty, we can use the TCC by assuming that a transmission function of the specimen does not depend on the incident beam direction. This is not always true, because dynamical scattering is important owing to strong interactions of electrons with the specimen. However, in the case of HREM, both the specimen thickness and the illumination angle should be small. Therefore we may neglect the dependency of the transmission function on the incident beam direction.

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