Thin film technology physical vapor deposition

Combustion Chemical Vapor Deposition (CCVD) allows deposition of thin films that confer special electronic, catalytic, or optical properties, corrosion and oxidation resistance. The CCVD process is a novel, open-atmosphere process that is environmentally friendly and does not require expensive reaction/vacuum chambers. Often coatings are of equal or better quality than those obtained by vacuum-based methods. Coating costs are significantly lower than for more traditional processes such as Chemical Vapor Deposition (CVD) and Physical Vapor Deposition (PVD). Equally important, this novel technology can be implemented in a production-line environment, thus enabling uninterrupted processing. To date over 70 different inorganic materials have been deposited onto a variety... 

For the formation of a metallic film in addition to thick film silk-screen technique, thin film metallization is another means for the film deposition. Deposition of thin film can be accomplished by either physical or chemical means, and thin film technology has been extensively used in the microelectronics industry. Physical means is basically a vapor deposition, and there are various methods to carry out physical vapor deposition. In general, the process involves the following 1) the planned deposited metal is physically converted into vapor phase and 2) the metallic vapor is transported at reduced pressure and condensed onto the surface of the substrate. Physical vapor deposition includes thermal evaporation, electronic beam assisted evaporation, ion-beam and plasma sputtering method, and others. The physical depositions follow the steps described above. In essence, the metal is converted into molecules in the vapor phase and then condensed onto the substrate. Consequently, the deposition is based on molecules and is uniform and very smooth. 

Thin film deposition technologies are widely used for the fabrication of microbatteries. They can be divided into two main categories Physical Vapor Deposition (PVD) and Chemical Vapor Deposition (CVD). 

Physical vapor deposition (PVD) is a technique for making thin films at low temperatures and is widely used in planar technology in electronics. It consists of evaporating or sputtering a solid, such as a metal, an alloy, or a mixture of solids, in a vacuum and condensing the compound on the substrate to be covered. In certain variations the vapor is reacted with gases introduced in the vacuum. That variation is reactive evaporation or reactive sputtering. The product can be a polycrystalline deposit or a powder. 

In thin film technology there is a distinction between physical vapor deposition (PVD) and chemical vapor deposition (CVD), a combination of types is available. All methods work in vacuum. The most important physical processes are evaporation and the sputtering. The material is introduced into the system as a solid (target). With an energy introduced into the target, they resolve atoms and molecules form a layer on the substrate. The layer thickness achieved is in the micrometer range. The layer composition substantially corresponds to that of the target. It can be pure metals, alloys, or dielectrics. 

U. Helmersson, M. Lattemann, J. Bohlmak, A.P. Ehiasarian, J.T. Gudmundsson, Ionized physical vapor deposition (IPVD) A review of technology and applications. Thin Solid Films 513 (2006) 1. 

Ionized Physical Vapor Deposition (IPVD) a review of technology and applications. Thin Solid Films, 513 (2006) 1. 

Thin semiconductor films (and other nanostructured materials) are widely used in many applications and, especially, in microelectronics. Current technological trends toward ultimate miniaturization of microelectronic devices require films as thin as less than 5 nm, that is, containing only several atomic layers [1]. Experimental deposition methods have been described in detail in recent reviews [2-7]. Common thin-film deposition techniques are subdivided into two main categories physical deposition and chemical deposition. Physical deposition techniques, such as evaporation, molecular beam epitaxy, or sputtering, involve no chemical surface reactions. In chemical deposition techniques, such as chemical vapor deposition (CVD) and its most important version, atomic layer deposition (ALD), chemical precursors are used to obtain chemical substances or their components deposited on the surface. 

The formation of ultrathin Me films on foreign substrates S (metals, superconductors, and semiconductors), S/Me, plays an important role in modern fields of technology such as micro- and nano-electronics, sensorics, electrocatalysis, etc. The process is often carried out by physical or chemical vapor deposition (PVD or CVD) of metals [6.152]. However, the difficult adjustment and control of the supersaturation via the gas flux is a great disadvantage of vapor deposition techniques. The situation becomes even more complicated, if more than one metal is deposited to form metallic sandwich layers and/or surface alloys. Therefore, electrochemical processes for the formation of ultrathin metal films and heterostructures became of great interest in modern thin layer technology. 

The most common commercial use of the QCM is as a thickness gauge in thin-layer technology. When used to monitor the thickness of a metal film during physical or chemical vapor deposition, it acts very closely as a nanobalance, providing a real-time measurement of the thickness. Indeed, devices sold for this purpose are usually calibrated in units of thickness (having a different scale for each metal, of course), and claim a sensitivity of less than 0.1 nm, which implies a sensitivity of less than a monolayer. 

Metal oxides display a variety of unique physical and chemical properties and are employed in numerous technological applications (Table 7-1). Chemical vapor deposition has been used widely for the preparation of metal oxide thin films [10, 13]. The following section summarizes the preparation of several transition metal and main group element oxides by CVD. 

Microfabrication has been the topic of a recent review in which thin-film (<1 pm, based on vacuum evaporation, sputtering or chemical vapor deposition) and thick-film (>10pm, based on screen printing or lamination) technologies are described for the mass production of potentiometric sensors and sensor arrays [80]. Current challenges include the cost of fabrication, especially for thin-film devices, the control of physical dimensions of the sensing elements, the incorporation of liquid reservoirs, and the stability of the integrated reference electrodes. 

Dupuis, R.D., Metalorganie chemical vapor deposition (MOCVD) in Handbook of Thin Film Process Technology, ed. by David A Glocker and S. Ismat Shah. Bristol Institute of Physics, 2002 1 p. B.l.1 5-6. 

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