Calcium electronic devices

Fig. 27. Scanning electron micrograph of polymer prepared from 3,9-bis (ethylidene-2,4,8,10-tetraoxaspiro [5,5] undecane) and a 60/40 mol ratio of rrans-cyclo-hexane dimethanol and 1,6-hexanediol. Polymer rods 2.4 x 20 mm containing 30 wt% levonorgestrei. and 2 wt% calcium lactate. Device implanted subcutaneously in rabbit for 10 weeks, 30X [25], Reprinted with permission...

Calcium titanate Calcium titanium oxide (CaTiOs) Calcium titanium trioxide EINECS 234-988-1 RC17 Titanate (Ti03 ), calcium (1 1) Perovskite Titanium calcium oxide. Inorganic compound used in electronic devices. Atomergic Chemefa/s Cerac f oflranselco Tam Ceramics. 

Alkaline earth metals The alkaline earth metals are in group 2. They are also highly reactive. Calcium (Ca) and magnesium (Mg), two minerals important for your health, are examples of alkaline earth metals. Because magnesium is solid and relatively light, it is used in the fabrication of electronic devices, such as the laptop shown in Figure 6.4. 

In some cases the Ila elements such as calcium are used as conductors or contacts, although their reactivity makes them too unstable in many cases. Finally, the group la alkali metals are rarely used because of their reactivity and rapid diffusion rates in many materials, although these too are becoming more common. Both group la and Ila elements are increasingly used, for example, in organic electronic devices. 

The devices used for the EL and PL measurements were fabricated in the thin film sandwich configuration anode/polymer/cathode. The electronic structure of alkoxy derivatives of PPV has been studied via internal field emission [42], internal photoemission [76], cyclovoltammetric spectroscopy [159]) and photoelectron spectroscopy [160]. The data indicate that the bottom of the Tr -band and the top of the ir-band are at 3 eV and 5 eV respectively, with respect to the vacuum. Thus, relatively good hole and electron injection can be achieved by using transparent indium/tin-oxide (ITO) as the anode and calcium (Ca) or barium (Ba) as the cathode [42,161]. In practice, however, hole injection is very sensitive to the quality of the ITO. A thin layer (= 300 A) of conducting polymer provides excellent, reproducible hole injecting contacts [70,71,162]. 

The first quantitative study of the device efficiency of polyfluorene LEDs was reported by Grice and co-workers in 1998.5 The LED used ITO-coated glass as the anode, a hole-transport layer of a polymeric triphenyldiamene (poly-TPD), an emissive layer of PFO, and a calcium cathode. A schematic energy-level structure for the device is inset in Fig. 10.14. The injection barrier for holes into poly-TPD is approximately 0.3 eV, much less than that for PFO (0.8 eV), and the injection barrier for electrons into PFO is approximately 0.1 eV. Poly-TPD had excellent film-forming properties, was transparent to PFO emission, and was insoluble in... 

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