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Sapphire fabrication

It is evident in Figure 3.5 that the two displayed spectra are slightly different in the band intensities and observed spectral features. This approach is thus suitable for analysing the characteristic band structures to enhance the bio-compatibility of the sapphire lenses, and the surface passivation process enabled more optimized biocompatible lenses to be fabricated. [Pg.50]

The fabrication process of vanadium oxide (VO2) has also been studied using RBS/C. Since optieal and electrical properties of VO2 are dramatically changed at 68°C due to phase transition, VO2 is regarded as one of the candidates for thermally activated electronic or optical switching devices for optieal fibers or sensors. To obtain the desired properties, the development of the fabrication process for very thin films, without crystalline defects on various substrates, is required. Single-crystalline VO2 thin films on (0001) plane of a sapphire substrate have been synthesized by a laser ablation method. The quality of VO2 was examined by X-ray diffraction and RBS/C method. The eleetrieal resistanee and the optical transmittance of the VO2 film were measured under inereasing and deereasing temperatures. At a temperature of 68 °C, an abrupt transition of resistanee from metal to... [Pg.843]

In the past, mica has been the material of choice for the interacting surfaces because of the ease of handling and since molecularly smooth surfaces can be fabricated mica surface coated with a thin film of other materials (e.g., lipid monolayers or bilayers, metal films, polymer films, or other macromolecules such as proteins) can also be used. The use of alternative materials such as molecularly smooth sapphire and silica sheets and carbon and metal oxide surfaces is also being explored. [Pg.53]

Epitaxial Layers. Epitaxial deposition produces a single crystal layer on a substrate for device fabrication or a layer for multilevel conductive interconnects which may be of much higher quality than the substrate. The epitaxial layer may have a different dopant concentration as a result of introducing the dopant during the epitaxial growth process or may have a different composition than the substrate as in silicon on sapphire. Methods used for epitaxial growth include chemical vapor deposition (CVD), vapor phase epitaxy (VPE), liquid phase epitaxy (LPE), molecular beam epitaxy (MBE) and solid phase epitaxy (SPE). [Pg.234]

A detector wafer 14 of HgCdTe is attached to a transmissive temporary substrate 10 of glass, quartz, alumina or sapphire by the use of a removable adhesive 12. The adhesive should not be soluble in the solvents used in the detector delineation and fabrication steps that will follow. Glycol phthalate is mentioned as an usable adhesive. [Pg.161]

The most common way of fabricating GalnN/GaN heterostructures is by means of heteroepitaxy of GaN and GalnN on sapphire or SiC substrates. In fact, this leads to wurtzite GaN, which is now the commonly used modification. Even though there is considerable effort being devoted to producing cubic GaN structures, we will restrict our discussion to the hexagonal phase, since practically all the work on heterostructures concentrates on the wurtzite structure. [Pg.514]

Two major improvements in the fabrication of an ion-sensitive FET that avoid most of the tedious polymer encapsulauon process have been reported. Matsuo and his coworkers (4, 37) fabricated a probe-type FET with a three-dimensional silicon nitride passivation layer around most of its surface, as shown in Fig. 2. The probe-type FET has one disadvantage Its fabrication requires a three-dimensional process that is uncommon for semiconductor construction facilities. An alternative approach utilizes a silicon-on-sapphire (SOS) wafer for FET fabrication (38, 39). The structure of a SOS-FET is depicted in Fig. 3. It has an island-like silicon layer on a sapphire substrate, in which an ion-sensitive FET is fabricated. The bare lateral sides do not need encapsulation because of the high insulation property of sapphire. [Pg.154]

Fig. 5. Top and cross-sectional views of a FET transducer fabricated with a silicon film on a sapphire wafer (SOS-FET). (Reproduced from Akiyama et al. (38), with permission.)... Fig. 5. Top and cross-sectional views of a FET transducer fabricated with a silicon film on a sapphire wafer (SOS-FET). (Reproduced from Akiyama et al. (38), with permission.)...
The nc-Si were fabricated by ion implantation of Si into fused quartz and crystalline C-cut sapphire at energies of 140 and 100 keV, respectively, to a dose of 1-lO cm. The samples were post-annealed at 1100 °C in dry nitrogen for 2 h. The transmission electron microscopy (TEM) showed the ensembles of nc-Si with average size of 3.2 nm and less than 12 nm non-uniformly distributed in Si02 and AI2O3 at the depths up to 200 and 350 nm, respectively [1,2]. [Pg.81]

Alumina films are used for surface coatings on carbide tools, as dielectric layers in transistor fabrication, as matched substrates (sapphire) for the growth of optically active materials such as gallium nitride, and as coatings for optical components. [Pg.171]


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See also in sourсe #XX -- [ Pg.127 ]




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