Skip to main content
main-content

About this book

This book presents the status quo of the structure, preparation, properties and applications of tetrahedrally bonded amorphous carbon (ta-C) films and compares them with related film systems. Tetrahedrally bonded amorphous carbon films (ta-C) combine some of the outstanding properties of diamond with the versatility of amorphous materials. The book compares experimental results with the predictions of theoretical analyses, condensing them to practicable rules. It is strictly application oriented, emphasizing the exceptional potential of ta-C for tribological coatings of tools and components.

Table of Contents

Frontmatter

Carbon Materials and Coatings

Frontmatter

Chapter 1. Carbon

Under all elements carbon represents an outstanding position concerning quantitative and qualitative aspects: On the one hand carbon is found in abundance in the universe and on the earth, on the other hand impressive top properties are realized by carbon materials. Both topics originate from carbon’s magic atomic number six.

Bernd Schultrich

Chapter 2. Diamond Films

The deposition of films from the gas phase allows the permanent and controlled manipulation of the growing structure. That way it is possible to realize unusual materials or to prepare well-known structures under unusual conditions. This concept is especially fruitful for carbon with its broad field of possible configurations. Important examples are the growth of diamond at low pressures and the preparation of amorphous carbons.

Bernd Schultrich

Chapter 3. Nanodiamond Films

Many applications demand a high smoothness of the diamond films. Subsequent laborious polishing procedures can be avoided by two complementary concepts: One way consists in the oriented growth of (100) faces, resulting in parallelized polycrystals with less pronounced boundaries.

Bernd Schultrich

Chapter 4. Amorphous Carbon Films

Carbon represents with its both crystalline modifications diamond and graphite two complementary features: superhard, insulating, transparent and soft, conductive, absorbing, respectively.

Bernd Schultrich

Chapter 5. Hydrogenated Amorphous Carbon Films (a-C:H)

The deposition of hydrogenated amorphous carbonHydrogenated amorphous carbon films may be considered as an extension of the conditions beyond the preparation of nanocrystalline diamond structures without the limitations of the crystalline diamond growth. Due to the abolition of crystalline perfection, lower substrate temperatures, higher carbon concentrations in the gas atmosphere and an intensified ion bombardment of the growing film are tolerated.

Bernd Schultrich

Structural Development of ta-C Films

Frontmatter

Chapter 6. Structure of Amorphous Carbon

This part reviews the structure of hydrogen-free tetrahedrally bonded amorphous carbon films. It starts with an overview on the corresponding structural characteristics and the methods for their determination by experiments or by simulations. The structures of ta-C films are discussed in their dependence on the sp3 content and in comparison to the structures of amorphous silicon and liquid carbon. The superficial top layers and ultrathin films show some structural pecularities. The influence of the deposition conditions, especially ion energy and substrate temperature, on the resulting film structure is presented. The corresponding empirical relations are the base for elucidation of the film formation. The growth process is presented as a combination of ion impact, short-time excitation with subsequent quenching and final relaxation. The various theoretical growth models are critically discussed.

Bernd Schultrich

Chapter 7. Influence of Deposition Conditions

The influence of the deposition conditions on the structure and the properties of the resulting amorphous carbon films is summarized in a number of reviews.

Bernd Schultrich

Chapter 8. Growth of ta-C Films

The understanding of the growth of tetrahedrally bonded amorphous carbon is based on the experimentally selected conditions for the preparation of ta-C films: sufficient high kinetic energy of the impinging carbon particles of at least some ten electron-volt and sufficient low temperatures, usually below 150 °C (see Chap. 7).

Bernd Schultrich

Vacuum Arc Deposition of Carbon Films

Frontmatter

Chapter 9. Vacuum Arc Discharges with Carbon Cathodes

The fundamental requirement for the growth of ta-C structures, a rather high kinetic energy of the film forming carbon species, can be fulfilled with excellent control by the Mass Selected Ion Beam Deposition.

Bernd Schultrich

Chapter 10. Methods of Vacuum Arc Deposition of ta-C Films

Vacuum arc dischargesArc discharge yield plasmas with usually complete ionization, high energy of the ions and high ion currents.

Bernd Schultrich

Chapter 11. Vacuum Arc with Particle Filtering

Driving the cathode spots over the target surface by strong external or intrinsic magnetic fields allows to reduce, but not to suppress the emission of target splinters.

Bernd Schultrich

Chapter 12. Special Arc Modes with Reduced Macroparticle Emission

A promising way towards arc deposited carbon films of higher perfectness consists in the reduction or even complete suppression of the macroparticle emission in addition to or instead of their troublesome separation.

Bernd Schultrich

Chapter 13. Vacuum Arc Equipment for Mass Production of ta-C Coatings

The outstanding tribological properties of ta-C and partially also of hard a-C films (see Vol. II, Part VII) suggest their broad application as wear protecting and friction reducing coatings. The realization of the corresponding mass production depends on the basic problem of any thin film technology, the extra costs in comparison to the gained performance.

Bernd Schultrich

Deposition of ta-C Films by Pulsed Laser and by Sputtering

Frontmatter

Chapter 14. Carbon Ablation with ns Lasers

In the pulsed laser deposition (PLD)Pulsed laser deposition (PLD) the target material is ablated by irradiation with very intense laser light. The outstanding feature of the pulsed laser depositionPulsed laser deposition (PLD) is its potential for the very efficient preparation of films with complex composition or complex layer structures. PLD works with any target material, even with very small quantities, may fast switch between different targets and functions at arbitrary temperatures and in high vacuum or reactive atmospheres, as well. These general advantages, which for example are very valuable in the development of high-temperature superconductors of the YBaCuO type, are of less interest in the case of amorphous carbon films, made of only one element, in high vacuum and at low temperatures.

Bernd Schultrich

Chapter 15. Carbon Film Deposition with ns Lasers

n dependence on the deposition conditions, amorphous carbon films cover a broad range of different structures and correspondingly varying properties. Apart from the directly determined sp3 content (e.g. by EELS or XPS), relevant properties allow to assess the realized film qualities (see Sect. 2.1.1). Table 15.1 summarizes orienting ta-C values for minimum sp3 content (50% per definition) and maximum achievable sp3 content (around 85%).

Bernd Schultrich

Chapter 16. Related Deposition Methods

The plasma arising from pulse laser excitation (for sufficient high intensities and especially with excimer lasersExcimer lasers) resembles the plasma of vacuum arc discharges

Bernd Schultrich

Chapter 17. Activated Sputter Deposition of ta-C Films

Sputtering represents the standard PVD method for the preparation of high quality thin films.

Bernd Schultrich

Backmatter

Additional information

Premium Partner

in-adhesivesMKVSNeuer Inhalt
image credits