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In this work, rutile-phase Ti[O.sub.2] particles (r-Ti[O.sub.2], about 360 nm in size) are embedded within a silicon oxide matrix using different concentration ratios of r-Ti[O.sub.2] with respect to Si[O.sub.2]:[H.sub.2]O, so that suspensions of mixed Ti[O.sub.2]:Si[O.sub.2] oxides were obtained and analyzed. These Ti[O.sub.2]:Si[O.sub.2] suspensions were deposited on previously-cleaned crystalline silicon and quartz substrates so that thin films of Ti[O.sub.2]:Si[O.sub.2] were obtained. All films were then exposed to relatively high-temperature thermal treatments in nitrogen and different characterization techniques were used to determine their physical and electrical properties before and after ultraviolet (UV) irradiation. Before high thermal treatment, X-ray diffraction patterns show that the main diffraction peaks for the obtained Ti[O.sub.2]:Si[O.sub.2] films correspond to the crystalline phase of rutile-Ti[O.sub.2]. Infrared analyses before and after thermal treatment show significant changes in the chemical bonding of the final films relative to the temperatures used during annealing. Also, UV-visible spectra provide a constant optical band gap for the films, independent of different Ti[O.sub.2] concentrations as expected. On the other hand, atomic-force microscopy measurements before and after UV irradiation show an appreciable difference in the grain size and surface morphology of the resulting Ti[O.sub.2]:Si[O.sub.2] oxides annealed at 1000 °C. Finally, photoelectrical I-V properties were obtained for all Ti[O.sub.2]:Si[O.sub.2] films by depositing ultrathin titanium stripes on top of the photoactive material and then, measuring the total current flowing through the metal electrode before and after UV irradiation. From these last measurements, a detectable increase in the I-V slope (lower resistance of the titanium stripe) is found for all samples during UV exposure, thus making this device to act as a simple photoresistor based on r-Ti[O.sub.2] particles. PACS Nos.: 78.67.Bf, 73.50.Pz, 61.80.Ba. Des particules de Ti[O.sub.2] en phase rutile (r-Ti[O.sub.2], environ 360 nm) sont ici implantees dans une matrice d'oxyde de silicium, utilisant differentes concentration de r-Ti[O.sub.2] relativement au Si[O.sub.2] : [H.sub.2]O, de facon a pouvoir obtenir et analyser differentes suspensions de Ti[O.sub.2] : Si[O.sub.2]. Ces suspensions sont deposees en films minces de Ti[O.sub.2] : Si[O.sub.2] sur des substrats de silicium cristallin et de quartz prealablement nettoyes. Tous les films sont recuits a relativement haute temperature dans une atmosphere d'azote et nous utilisons differentes techniques pour caracteriser leurs proprietes physiques et electriques avant et apres leur irradiation aux ultraviolet (UV). Avant le traitement thermique, les patrons de diffraction X indiquent que les principaux pics de diffraction des films de Ti[O.sub.2] : Si[O.sub.2] correspondent a la phase cristalline de r-Ti[O.sub.2]. L'analyse infrarouge avant et apres le traitement thermique montre des changements significatifs dans le lien chimique des films finaux selon les temperatures utilisees pour le recuit. De plus, la spectroscopie UV-visible indique un gap optique constant pour les films, independamment de la concentration en Ti[O.sub.2], tel qu'attendu. D'un autre cote, la microscopie a force atomique avant et apres l'irradiation UV montre une difference appreciable de la grosseur du grain et de la morphologie de surface des oxydes resultants Ti[O.sub.2] : Si[O.sub.2] soumis a un recuit a 1000°C. Finalement, nous determinons les proprietes photoelectriques I-V de tous les films de Ti[O.sub.2] : Si[O.sub.2], en deposant sur le materiau photo-actif une ultra-mince languette de titane et en mesurant le courant total dans cette electrode metallique avant et apres l'irradiation aux UV. De ces mesures, nous trouvons une augmentation detectable dans la pente I-V (plus basse resistance de la languette de Ti) pour tous les echantillons durant l'exposition aux UV, determinant ainsi que ce dispositif est une simple photoresistance basee sur les particules de r-Ti[O.sub.2]. [Traduit par la Redaction], 1. Introduction Since the 1920s, titanium dioxide (Ti[O.sub.2]) has been produced commercially for applications in paints, sunscreens, toothpaste, pigments, etc., but it was not until 1972 that Fujishima and Honda [...]

The cryogenic self heating of integrated Si devices is described.

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In this work, rutile-phase TiO2 particles (r-TiO2, about 360 nm in size) are embedded within a silicon oxide matrix using different concentration ratios of r-TiO2 with respect to SiO2:H2O, so that suspensions of mixed TiO2:SiO2 oxides were obtained and analyzed. These TiO2:SiO2 suspensions were deposited on previously-cleaned crystalline silicon and quartz substrates so that thin films of TiO2:SiO2 were obtained. All films were then exposed to relatively high-temperature thermal treatments in nitrogen and different characterization techniques were used to determine their physical and electrical properties before and after ultraviolet (UV) irradiation. Before high thermal treatment, X-ray diffraction patterns show that the main diffraction peaks for the obtained TiO2:SiO2 films correspond to the crystalline phase of rutile-TiO2. Infrared analyses before and after thermal treatment show significant changes in the chemical bonding of the final films relative to the temperatures used during annealing. Also, UV-visible spectra provide a constant optical band gap for the films, independent of different TiO2 concentrations as expected. On the other hand, atomic-force microscopy measurements before and after UV irradiation show an appreciable difference in the grain size and surface morphology of the resulting TiO2:SiO2 oxides annealed at 1000 °C. Finally, photoelectrical I-V properties were obtained for all TiO2:SiO2 films by depositing ultrathin titanium stripes on top of the photoactive material and then, measuring the total current flowing through the metal electrode before and after UV irradiation. From these last measurements, a detectable increase in the I-V slope (lower resistance of the titanium stripe) is found for all samples during UV exposure, thus making this device to act as a simple photoresistor based on r-TiO2 particles. [ABSTRACT FROM AUTHOR]