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The mechanical properties of thermally grown oxide films on various aluminum substrates were tested using nanoindentation. A sudden discontinuity, indicative of film fracture, was observed upon loading portion of the load-depth curve. The 63-nm-thick films were determined to have ultimate strengths between 4.8 and 8.9 GPa. The ultimate stress is a superposition of the bending and membrane stress. The stress intensity at fracture for each of the films was developed by approximating the resulting bending moment and various cracks sizes. At a constant ratio of crack size to oxide thickness of 0.3, the applied stress intensity at fracture of these aluminum oxide films were between 0.46 and 1.20 MPa m 1/2 . The residual stress in the film was assumed to be negligible in the stress intensity calculation.

The use of continuous load and depth monitoring indentation methods for measuring the mechanical properties of small volumes in conjunction with orientation imaging microscopy (OIM) and atomic force microscopy (AFM) is presented for a model system. Because many materials for microelectronics are processed in hydrogen-containing atmospheres, a model system is needed to show how OIM and AFM can be coupled to determine slip behavior on the nanometer to micrometer length scale as a function of hydrogen concentration. Atomic force microscopy imaging alone is not able to quantify the slip behavior, but coupling AFM and OIM demonstrates how changes in hardness can be linked to changes in slip band formation.

Utilizing indentation techniques coupled with atomic-force microscopy (AFM) and orientation-imaging microscopy (OIM), it is possible to identify both out-of-plane deformation and slip-band formation around nanoindentations. These effects are due to both strain hardening and cross slip. The effects of hydrogen on body-centeredcubic and face-centered-cubic alloys were tested using nano-and microindentation and show a distinctive change in deformation morphology. Localized slip steps on the surface were examined using OIM and AFM. The frequency of slip steps (number of planes between each step) is not significantly influenced by hydrogen concentration, but the overall height of each step is reduced in the presence of hydrogen.

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