Growth of thin film

Lewis B and Anderson J C 1978 Nucleation and Growth of Thin Films (New York Academic)... 

Venables J A, Spiller G D T and Hanbucken M 1984 Nucleation and growth of thin-films Rep. Prog. Phys. 47 399... 

P. Jensen, B. Niemeyer. The effect of a modulated flux on the growth of thin films. Surf Sci 384 9999, 1997. 

Epitaxial growth of thin films usually involves the formation of strained material as a result of mismatch between the film and substrate and because of the large surface to volume ratio in the film. Surface stress can be a major factor, even when the lattice constants of film and substrate are perfectly matched. Although it appears to be difficult to eliminate the stress totally, it is important to be able to control it and even use it to produce desired qualities. 

Historically, EC-ALE has been developed by analogy with atomic layer epitaxy (ALE) [76-82], ALE is a methodology used initially to improve epitaxy in the growth of thin-films by MBE and VPE. The principle of ALE is to use surface limited reactions to form each atomic layer of a deposit. If no more than an atomic layer is ever deposited, the growth will be 2-D, layer by layer, epitaxial. Surface limited reactions are developed for the deposition of each component element, and a cycle is formed with them. With each cycle, a compound monolayer is formed, and the deposit thickness is controlled by the number of cycles. 

CdTe Wall jet flow cell growth of thin films 1999 [114]... 

MBE (molecular beam epitaxy), which involves epitaxial growth of thin films on either the same material as substrate (homoepitaxial) or a lattice-matched substrate (heteroepitaxial) the heated substrate reacts with a molecular beam of compounds containing the constituent elements of the semiconductor as well as any dopants the resultant film is essentially a single crystal slow growth rates produce films from a few nanometers thick to at most several hundred nanometers that have very high purity and controlled levels of dopants. 

Besides the inelastic component, always a certain number of He atoms are elastically scattered in directions lying between the coherent diffraction peaks. We will refer to this scattering as diffuse elastic scattering. This diffuse intensity is attributed to scattering from defects and impurities. Accordingly, it provides information on the degree and nature of surface disorder. It can be used for example to study the growth of thin films or to deduce information on the size, nature and orientation of surface defects Very recently from the analysis of the diffuse elastic peak width, information on the diffusive motion of surface atoms has been obtained. ... 

Venables JA, Spiller GDT, Hanbucken M (1984) Nucleation and growth of thin-films. Rep Prog Phys 47 399 59... 

The growth of thin films on solid surfaces is important in technology, and nucleation is one of the keys for understanding the growth mechanism. The ability of STM to image local structures down to atomic detail makes it ideal for the study of nucleation, thin film growth, and crystal growth. 

This process has the advantage of low-temperature deposition, which may be needed for the growth of thin films on temperature-sensitive substrates such as compound semiconductors and polymers. If a laser is used as the light source, fine lines of materials can be written directly, and possibly, lithographic steps can be avoided and damaged lines can be repaired. 

There are four types of fundamental subjects involved in the process represented by Eq. (1.1) (1) metal-solution interface as the locus of the deposition process, (2) kinetics and mechanism of the deposition process, (3) nucleation and growth processes of the metal lattice (M a[tice), and (4) structure and properties of the deposits. The material in this book is arranged according to these four fundamental issues. We start by considering the basic components of an electrochemical cell for deposition in the first three chapters. Chapter 2 treats water and ionic solutions Chapter 3, metal and metal surfaces and Chapter 4, the metal-solution interface. In Chapter 5 we discuss the potential difference across an interface. Chapter 6 contains presentation of the kinetics and mechanisms of electrodeposition. Nucleation and growth of thin films and formation of the bulk phase are treated in Chapter 7. Electroless deposition and deposition by displacement are the subject of Chapters 8 and 9, respectively. Chapter 10 contains discussion on the effects of additives in the deposition and nucleation and growth processes. Simultaneous deposition of two or more metals, alloy deposition, is discussed in Chapter 11. The manner in which... 

Consider an example from nucleation and growth of thin films. At least three length scales can be identified, namely, (a) the fluid phase where the continuum approximation is often valid (that may not be the case in micro- and nanodevices), (b) the intermediate scale of the fluid/film interface where a discrete, particle model may be needed, and (c) the atomistic/QM scale of relevance to surface processes. Surface processes may include adsorption, desorption, surface reaction, and surface diffusion. Aside from the disparity of length scales, the time scales of various processes differ dramatically, ranging from picosecond chemistry to seconds or hours for slow growth processes (Raimondeau and Vlachos, 2002a, b). 

Low pressure CVD (LPCVD) has become a dominant process in the growth of thin films of microelectronic materials. It is widely used to deposit thin films of polycrystalline Si, Si02, and Si3N4 In addition it has been demonstrated for deposition of metals, specifically Al and W. The process is carried out in tubular, hot wall reactors where the wafers are placed perpendicular to the flow direction as illustrated in Figure 2. The very large packing densities that can be realized in LPCVD reactors without adverse... 

Many different embodiments of the CVD techniqne are available for the growth of thin films, and the readers is referred to excellent recent monographs for more detail. " The last review on metal-organic precursors that appeared in this encyclopedia contained a detailed overview of thermal CVD processes, schematics of several reactors, as well as a listing of common variants of thermal CVD processes. In addition to these well-known techniques, several new CVD techniqnes have gained importance in recent years. 

The motion of atoms both in and on the surface can also occur through surface diffusion. The concept of atom transport along the surface plane is important in equihbrium surface structure, nucleation and growth of thin films, and surface reactivity. 

The steps involved in the growth of thin films by CVD are shown in Figure 4.36. Once the gas-phase precursor molecules enter the deposition zone (a), they are physisorbed to the substrate surface through weak van der Waals interactions (b). The ancillary ligands are removed through thermolysis, leaving the desired residual... 

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