Surface erosion of BaF2 thin films under SHI irradiation: Angular distribution and role of different substrates

The present work reports phase transformations of thin films of C60 irradiated with 100 MeV 197Au8+ ions. This work is in continuation with our earlier work using 58Ni10+ and 16O6+ ions, to study the modification in C60 thin films. The study of C60 thin films using 197Au8+ ions, provides us enough additional data to investigate thoroughly the role of Se in causing phase transformations under different ion fluences. The Raman spectra indicate that swift heavy ion (SHI) irradiation results in several transformations of crystalline C60. At low fluences along with the fragmentation of C60 there is dimer/polymer formation. As fluence increases the dimer/polymer content first rises, optimizes, decreases and finally vanishes at very high fluences. At high fluences, all the C60 molecules as well as the polymer C60 break up, possibly resulting in nano-crystalline graphite embedded in amorphous carbon (a-C).

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The study of interfacial reactions of nickel thin films on GaAs

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100074616 ◽

1983 ◽

Vol 41 ◽

pp. 156-157

Author(s):

L.J. Chen ◽

Y.F. Hsieh

Keyword(s):

Thin Films ◽

Integrated Circuits ◽

Interfacial Reactions ◽

Metal Contacts ◽

Nickel Thin Films ◽

Thin Foils ◽

The Status ◽

Si Doped ◽

Electron Microscopes

One measure of the maturity of a device technology is the ease and reliability of applying contact metallurgy. Compared to metal contact of silicon, the status of GaAs metallization is still at its primitive stage. With the advent of GaAs MESFET and integrated circuits, very stringent requirements were placed on their metal contacts. During the past few years, extensive researches have been conducted in the area of Au-Ge-Ni in order to lower contact resistances and improve uniformity. In this paper, we report the results of TEM study of interfacial reactions between Ni and GaAs as part of the attempt to understand the role of nickel in Au-Ge-Ni contact of GaAs.N-type, Si-doped, (001) oriented GaAs wafers, 15 mil in thickness, were grown by gradient-freeze method. Nickel thin films, 300Å in thickness, were e-gun deposited on GaAs wafers. The samples were then annealed in dry N2 in a 3-zone diffusion furnace at temperatures 200°C - 600°C for 5-180 minutes. Thin foils for TEM examinations were prepared by chemical polishing from the GaA.s side. TEM investigations were performed with JE0L- 100B and JE0L-200CX electron microscopes.

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Transmission Electron Microscopy studies of texture of Cr underlayer of magnetic recording hard disk

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100087215 ◽

1991 ◽

Vol 49 ◽

pp. 580-581

Author(s):

L. Tang ◽

G. Thomas ◽

M. R. Khan ◽

S. L. Duan

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

Transmission Electron Microscopy ◽

Magnetic Recording ◽

Magnetic Thin Films ◽

Magnetic Films ◽

Substrate Bias ◽

Epitaxial Relationship ◽

Transmission Electron

Cr thin films are often used as underlayers for Co alloy magnetic thin films, such as Co1, CoNi2, and CoNiCr3, for high density longitudinal magnetic recording. It is belived that the role of the Cr underlayer is to control the growth and texture of the Co alloy magnetic thin films, and, then, to increase the in plane coercivity of the films. Although many epitaxial relationship between the Cr underlayer and the magnetic films, such as ﹛1010﹜Co/ {110﹜Cr4, ﹛2110﹜Co/ ﹛001﹜Cr5, ﹛0002﹜Co/﹛110﹜Cr6, have been suggested and appear to be related to the Cr thickness, the texture of the Cr underlayer itself is still not understood very well. In this study, the texture of a 2000 Å thick Cr underlayer on Nip/Al substrate for thin films of (Co75Ni25)1-xTix dc-sputtered with - 200 V substrate bias is investigated by electron microscopy.

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Transmission Electron Microscopy of Evaporated Perylene Thin Films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100135289 ◽

1990 ◽

Vol 48 (2) ◽

pp. 336-337

Author(s):

C. Ewins ◽

J.R. Fryer

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

Transmission Electron Microscopy ◽

Molecular Electronics ◽

High Vacuum ◽

Amorphous Layer ◽

Electric Heater ◽

Transmission Electron ◽

Polycyclic Aromatic

The preparation of thin films of organic molecules is currently receiving much attention because of the need to produce good quality thin films for molecular electronics. We have produced thin films of the polycyclic aromatic, perylene C10H12 by evaporation under high vacuum onto a potassium chloride (KCl) substrate. The role of substrate temperature in determining the morphology and crystallography of the films was then investigated by transmission electron microscopy (TEM).The substrate studied was the (001) face of a freshly cleaved crystal of KCl. The temperature of the KCl was controlled by an electric heater or a cold finger. The KCl was heated to 200°C under a vacuum of 10-6 torr and allowed to cool to the desired temperature. The perylene was then evaporated over a period of one minute from a molybdenum boat at a distance of 10cm from the KCl. The perylene thin film was then backed with an amorphous layer of carbon and floated onto copper microscope grids.

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