A Tribute to Professor Gaetano Granozzi and His Contributions to Surface Science on the Occasion of His 70th Birthday

The use of lasers for surface annealing, heating and/or damage has become a routine practice in the study of materials. Lasers have been closely looked at as an annealing technique for silicon and other semiconductors. They allow for local heating from a beam which can be focused and tuned to different wavelengths for specific tasks. Pulsed dye lasers allow for short, quick bursts which can allow the sample to be rapidly heated and quenched. This short, rapid heating period may be important for cases where diffusion of impurities or dopants may not be desirable.At Northwestern University, a Candela SLL - 250 pulsed dye laser, with a maximum power of 1 Joule/pulse over 350 - 400 nanoseconds, has been set up in conjunction with a Hitachi UHV-H9000 transmission electron microscope. The laser beam is introduced into the surface science chamber through a series of mirrors, a focusing lens and a six inch quartz window.

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Quantitative surface damage studies by H.R.E.M.

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010015513x ◽

1989 ◽

Vol 47 ◽

pp. 632-633

Author(s):

S. R. Singh ◽

H. J. Fan ◽

L. D. Marks

Keyword(s):

Solar Wind ◽

Quantitative Analysis ◽

Surface Science ◽

Surface Damage ◽

Space Environment ◽

Oxygen Desorption ◽

The Past ◽

Diffusion Controlled ◽

Original Observation ◽

Substantial Interest

Since the original observation that the surfaces of materials undergo radiation damage in the electron microscope similar to that observed by more conventional surface science techniques there has been substantial interest in understanding these phenomena in more detail; for a review see. For instance, surface damage in a microscope mimics damage in the space environment due to the solar wind and electron beam lithographic operations.However, purely qualitative experiments that have been done in the past are inadequate. In addition, many experiments performed in conventional microscopes may be inaccurate. What is needed is careful quantitative analysis including comparisons of the behavior in UHV versus that in a conventional microscope. In this paper we will present results of quantitative analysis which clearly demonstrate that the phenomena of importance are diffusion controlled; more detailed presentations of the data have been published elsewhere.As an illustration of the results, Figure 1 shows a plot of the shrinkage of a single, roughly spherical particle of WO3 versus time (dose) driven by oxygen desorption from the surface.

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Modifications of a JEOL 2000EX TEM for insSitu surface studies

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100149039 ◽

1993 ◽

Vol 51 ◽

pp. 640-641

Author(s):

Michael T. Marshall ◽

Xianghong Tong ◽

J. Murray Gibson

Keyword(s):

Electron Diffraction ◽

Surface Science ◽

Film Growth ◽

High Vacuum ◽

High Energy ◽

Energy Electron ◽

Ultra High Vacuum ◽

Transmission Electron ◽

Fundamental Insight

We have modified a JEOL 2000EX Transmission Electron Microscope (TEM) to allow in-situ ultra-high vacuum (UHV) surface science experiments as well as transmission electron diffraction and imaging. Our goal is to support research in the areas of in-situ film growth, oxidation, and etching on semiconducter surfaces and, hence, gain fundamental insight of the structural components involved with these processes. The large volume chamber needed for such experiments limits the resolution to about 30 Å, primarily due to electron optics. Figure 1 shows the standard JEOL 2000EX TEM. The UHV chamber in figure 2 replaces the specimen area of the TEM, as shown in figure 3. The chamber is outfitted with Low Energy Electron Diffraction (LEED), Auger Electron Spectroscopy (AES), Residual Gas Analyzer (RGA), gas dosing, and evaporation sources. Reflection Electron Microscopy (REM) is also possible. This instrument is referred to as SHEBA (Surface High-energy Electron Beam Apparatus).The UHV chamber measures 800 mm in diameter and 400 mm in height. JEOL provided adapter flanges for the column.

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Development of the UHV-STM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100180367 ◽

1990 ◽

Vol 48 (1) ◽

pp. 322-323

Author(s):

M. Iwatsuki ◽

S. Kitamura ◽

A. Mogami

Keyword(s):

Surface Science ◽

Real Space ◽

Atomic Scale ◽

Scanning Tunneling ◽

Great Promise ◽

Force Microscopy ◽

Atomic Force ◽

Stm Image ◽

Surface Construction ◽

Very High

Since Binnig, Rohrer and associates observed real-space topographic images of Si(111)-7×7 and invented the scanning tunneling microscope (STM),1) the STM has been accepted as a powerful surface science instrument.Recently, many application areas for the STM have been opened up, such as atomic force microscopy (AFM), magnetic force microscopy (MFM) and others. So, the STM technology holds a great promise for the future.The great advantages of the STM are its high spatial resolution in the lateral and vertical directions on the atomic scale. However, the STM has difficulty in identifying atomic images in a desired area because it uses piezoelectric (PZT) elements as a scanner.On the other hand, the demand to observe specimens under UHV condition has grown, along with the advent of the STM technology. The requirment of UHV-STM is especially very high in to study of surface construction of semiconductors and superconducting materials on the atomic scale. In order to improve the STM image quality by keeping the specimen and tip surfaces clean, we have built a new UHV-STM (JSTM-4000XV) system which is provided with other surface analysis capability.

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