Pulsed layer deposition

Figure 2 Nyquist plots of the normalized impedance results of 15 x 8 x 8 supercells obtained from kinetic Monte Carlo (KMC) simulations at 400 K compared with the results from the electrochemical impedance spectroscopy (EIS) measurements on a pulsed layer-deposited polycrystalline thin film YSZ (100 nm in thickness) at 336°C. Reprinted from Reference [115], copyright 2007, with permission from Elsevier.

Yang D, Zhang X, Nikumb S, Deces-Petit C, Hui R, Marie R et al. Low temperature solid oxide fuel cells with pulsed laser deposited bi-layer electrolyte. J. Power Sources 2007 164 182-188. 

A.B.M. Ismail, T. Harada, T. Yoshinobu, H. Iwasaki, M.J. Schoning and H. Liith, Investigation of pulsed laser-deposited A1203 as a high pH-sensitive layer for LAPS-based biosensing applications, Sens. Actuators B Chem., 71(3) (2000) 169-172. 

Engineering the required texture in a (RE)BCO tape is a much more complex matter than in the case of the Bi-2223 tape. One approach is to prepare a nickel tape with a carefully controlled crystalline surface texture. This forms the substrate for the development of a correspondingly textured thermally grown oxide layer which, in turn, forms the substrate for the epitaxial growth of MgO by electron beam evaporation. The textured MgO serves as the substrate for the epitaxial growth of the 1 /mi thick (RE)BCO via pulsed laser deposition. 

Atomic layer deposition (also termed atomic layer epitaxy) a process in which alternate pulses of two volatile precursors are passed over the substrate to promote layer-by-layer film growth... 

The chemistry of ALD is similar to that of CVD, except that ALD makes nse of sequential precursor gas pulses to deposit a film layer-by-layer ALD film growth is selflimited and based on surface reactions, which makes achieving atomic-scale deposition control possible (monolayers can be obtained). In principle, the first ALD precnrsor is introduced into the process reactor producing only an adsorbed monolayer on the snbstrate surface because it cannot decompose completely without a second componnd. After the second precursor is brought into the reactor chamber it reacts with the first precnrsor to afford the desired monolayer, as illustrated in Figure 2. Since each of such cycles produces exactly one monolayer, the thickness of the resulting film may be precisely controlled by the number of deposition cycles. 

Pulse metal deposition offers the possibility of producing alloy layers as well as multilayered systems. If, e.g., the metal ion discharge of the components of an alloy follows different Tafel characteristics, a defined alloy composition can be achieved by an appropriate potentiostatic pulse routine as shown for the deposition of brass, bronze, and other binary and ternary alloys within a wide compositional range. Furthermore, alloys with changing composition gradients, which are of high technical interest, can be produced. 

In general, these methods are used for the production of nanocrystalline powders which may be further compacted via techniques such as hot-pressing [157, 158] or magnetic pulsed compaction [159, 160]. In addition, other types of nanoionic material maybe prepared, such as nanometer-thin films, using techniques including molecular beam epitaxy [161], pulsed laser deposition [162] or spin-coating methods [163]. Novel structures, such as core-shell [164—166] and multi-layered [167, 168] (so-called onion structures) materials, may also be produced in this way. 

BOU 03] BOULLE A., CANALE L., GUINEBRETIERE R GIRAULT-DIBIN C., DAUGER A., Defect structure of pulsed laser deposited LiNbOj/ALOs layers determined by XRD reciprocal space mapping Thin Sol. Films, vol. 429, p. 55-62,2003. 

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