Polyimides have been extensively studied in view of their wide industrial applications. Adhesion to a substrate is essential for normal operation of devices. This problem is often solved by the use of an adhesion promoter on the surface of interest. A surface‐sensitive technique such as XPS has proved to be a powerful analytical tool for the analysis of the polymer/substrate interface. In the present paper, the interfaces of the SiO2/γ‐aminopropyltriethoxysilane (γ‐APS)/Pyralin system have been investigated at a precured stage. A detailed analysis of the molecular structures formed at the interface is carried out using XPS spectroscopy. An attribution of the various peak components is made with the help of accurate calculations of presumed core‐electron binding energies using a recent procedure based on the Density Functional Theory. Two acid–base mechanisms are described. The first one occurs between the ammonium end of the γ‐APS molecule and the silicon surface hydroxyl (NH3U+SiO‐), whereas the second one is formed between the ammonium end of the γ‐APS and the polymer carboxylic function (NH3U+COO‐). The results at the first interface are in contradiction with the expected stable oxygen‐bridged bond (siloxane), thus the rearrangement of the γ‐APS molecule upon heating, as suggested by Linde in a dynamic ‘Flip model,’ has been studied.

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The concentration of several electron-irradiation-induced deep defect levels in Inp has been measured by deep-level transient spectroscopy as a function of electron energy. The dominant centers exhibit a threshold at about 100 keV, which clearly points to a primary production event by electronphosphorus-atom collision. This unambiguous determination allowed a test of the recently proposed orientation dependence technique to find the nature of the sublattice involved in the collision process for III-V compounds. A good quantitative agreement is obtained with a hard-sphere model for secondary collisions if disorientation of the beam in the sample is taken into account. Other traps exhibit higher thresholds which correspond either to indium-atom displacements or to the involvement of secondary collisions in the production event.