Practical limitations to indentation testing of thin films

A method that is becoming increasingly common for measuring the mechanical behavior of thin films is low-load indentation testing. However, there can be complications in interpreting the results as many factors can affect hardness and moduli measurements such as surface roughness and determination of the indentation contact area. To further the understanding, the mechanical properties of thin (50 nm) films of AlN on sapphire substrates were evaluated using a scanning force microscopy (SFM) based pico-indentation device to allow imaging of the surface and indentations. The primary emphasis was the types of problems or limitations involved in testing very thin, as deposited films in which properties are desired over indentation depths less than 50 nm

Influence of substrate temperature and ion-beam energy on the syntheses of aluminium nitride thin films by nitrogen-ion-assisted pulsed-laser deposition

10.1007/s00339-002-1452-2Applied Physics A: Materials Science and Processing773-4433-439APAM

Investigation of nickel product structures developed during the gaseous reduction of solid nickel oxide

The product microstructures developed during the reduction of dense synthetic nickel oxide in H-2-N-2 and H-2-H2O mixtures between 300 A degrees C and 1000 A degrees C are reported. A number of distinctly different types of nickel product structures have been identified, namely, coarse fibrous nickel with fissures, fine porous nickel-planar interface, large porous nickel-irregular interface, and dense nickel layer. The influences of gas composition and temperature on the conditions for formation of these microstructures, and their evolution with temperature and time, have been systematically investigated. The condition for formation of the various microstructure types was summarized on morphology maps as functions of reducing gas partial pressure, thermodynamic driving force, and reaction temperature