Thin film deposition techniques/processing

Research on nano- and micro-fabrications based on anodizing treatments combined with chemical/mechanical processes such as laser irradiation, atomic force micro-probe processing and thin film deposition techniques... 

Like any other thin-film deposition techniques, sol-gel processing is essentially a mass transport process. The transformation of a liquid solution to a solid crystalline film is accomplished through three steps ... 

In addition to a lattice-matched substrate, sol-gel epitaxy also requires excellent stoichiometry control of the solution. Most of the demonstrated sol-gel epitaxies were performed at relatively low temperatures. Therefore, molecular-level homogeneity is essential. To appreciate fully the delicate features of sol-gel epitaxy, it is now appropriate to compare sol-gel processing with other thin-film deposition techniques. 

In the attempt to achieve optical signal processing, modulation, amplification, and memory functions in integrated circuits similar to those on electrical signals by semiconductor devices, integration of ferroelectric devices is the ultimate goal. However, to achieve integration of microscopic devices based on materials as complex as oxide ferroelectrics, which are predominantly multi-component metal oxide compounds, reliable thin-film deposition techniques are critically needed. One of the most important aspects of multicomponent oxide thin-film deposition is the control of stoichiometry. 

Sputtering Thin film deposition technique based on the momentum transfer between accelerated ions and a target of source material. The process is undertaken at reduced pressure. 

Thin-film deposition technique in which a material is formed from a beam of sublimated atoms. The MBE process is valued for its precise control of atomic species on the growth surface, both for desired and undesired species. 

Thin-film deposition technique which uses a radio frequency (e.g., 13.56 MHz) to create a plasma consisting of ions of a process gas (Ar in the case of this investigation). These ions are accelerated into a target material to remove atoms of the material, which are then deposited onto a substrate to form a thin film. 

Traditionally, thin-film deposition techniques have been related to the semiconductor industry and not to the biomedical sector. This is mainly due to the extreme conditions generally required for the material deposition process and their lack of compatibility with biological systems. However, the interdisciplinary characteristics of biosensors and POC devices has opened an entirely new range of applications for these techniques, mainly orientated towards the fabrication of platforms that can be employed as both the transducer for the sensing process and the support for the immobilization of the recognition molecule (Lin and Yan, 2012 Ceylan Koydemir et al., 2013). 

The fundamental aspect for creating these tanplated nanomaterials is relatively straightforward. First, the template, a variety of which will be discussed in the next section, is positioned on a current collector, or one is applied to it through a thin film deposition technique such as thermal or e-beam evaporation. The tanplate is then placed in the electrochemical plating bath. Electrodeposition of the material occurs through the template pores or along their walls. This is followed by the removal of the template through mostly chemical processes such as dissolution however, other processes such as thermal decomposition can be used. 

Zilko, J. L., Metallo-Organic CVD Technology and Equipment, in Handbook of Thin-Film Deposition Processes and Techniques, (K. K. Shuegraf, ed.), Noyes Publications, Park Ridge, NJ (1988)... 

K. K. Schuegraf, Handbook of Thin-Film Deposition Processes and Techniques, Noyes, Park Ridge, NJ, 1988. 

After the precursor stock solution is prepared, various techniques can be used to coat the substrate, depending on the solution viscosity, required film thickness and coverage. The most common methods in the semiconductor industry are spin- and dip-coating. Other processes that are used for deposition include spray coating and stamping. A summary of the uses, limitations, and advantages of the various thin film deposition methods is reported in Table 2.2. 

Ranjith, R. John T. T. Kartha C. S. Vijayakumar K. P. Abe T. Kashiwaba Y. 2007. Post-deposition annealing effect on In2S3 thin films deposited using SILAR technique. Mater. Sci. Semicond. Process. 10 49-55. 

It should be noted that a Z2 dependence of the cross section makes the process very sensitive for heavier elements but proportionately less so for lighter elements. This effect can be observed in Figure 1 when it is noted that the Au peak indicates the presence of only about 0.04j Au compared to about 5056 for the 0 peak. In the latter case the sensitivity is further degraded by the superposition of the 0 peak from the thin film with the distribution from the thick underlying Si substrate. It should be further noted here that the Si substrate is prevented from interfering with other elements by the special preparation of the substrate by placing a film of C on its surface before deposition of the sample thin film. This technique is useful when one has the opportunity to choose the substrate. 

HANDBOOK OF THIN FILM DEPOSITION PROCESSES AND TECHNIQUES Principles, Methods, Equipment and Applications edited by Klaus K, Schuegraf... 

The potential benefits of CVD over other film deposition techniques are that CVD-derived films can be deposited under conditions that give conformal coverage, they can be deposited at low temperatures, there can be a high level of compositional control, thin layers can be deposited, the technique can be scaled to coat large areas uniformly, and there is also the possibility for area-selective deposition13 as a result of the chemical nature of this process. The details of CVD and related chemical deposition processes such as atomic layer epitaxy (ALE), organometallic vapor-phase epitaxy (OMVPE), and others have been described elsewhere.6... 

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