Metal-semiconductor system

Cowley AM, Sze SM (1965) Surface states and barrier height of metal-semiconductor systems. J Appl Phys 36 3212-3220... 

Greenian for infinite semiconductor g2 Greenian for semi-infinite semiconductor 312 composite Greenian for metal-semiconductor system... 

Besides single-component photo catalysts, heterogeneous metal-semiconductor systems, such as Pt/TiCh, Pd/Ti02, Ag/TiC>2, and Cu/TiCh [39-41],... 

This is an intermediate combination of the two growth modes mentioned above. The substrate is first covered with one or a few monolayers grown in Frank-van der Merwe mode, then some three-dimensional islands are formed on the surface in the Volmer-Weber growth mode. This mode is a transition from two-dimensional growth to three-dimensional growth and has been observed in metal-metal and metal-semiconductor systems. 

Given such postulated, but not general, rate equations, a variety of methods is available for evaluating the rate parameters. We will consider the uniqueness or otherwise of the rate parameters subsequently, but first we will describe briefly the analytical procedures with specific reference to their application to metal—semiconductor systems. The simplest, and in many cases most accurate, is the peak temperature method first described by Redhead [63]. AE can be directly obtained by measuring the temperature, Tp, at which the desorption rate is a maximum, then by setting d2n/dt2 = 0, an expression for AE can be derived in terms of v, Tp and the known heating rate 3 v is usually assumed to be 1013 s-1. 

Thus, although the examples are rather limited, it appears that the large amount of interdiffusion which characterizes many metal—semiconductor systems does not occur with semiconductor heterojunctions. This would imply that the mechanism proposed by Spicer et al. [298, 326, 327] in terms of the heat of condensation of the overlayer is not universally applicable. The fundamental difference between semiconductor and metal deposits is that the latter induce instability in the covalent bonding of the semiconductor substrate, perhaps by their ability to screen Coulomb interactions due to their mobile free electrons. 

How special is this topic for ceramics These processes do occur in metal/semiconductor systems. In ceramics, solid-state reactions usually involve the movement of two species because the species are likely to be charged and we must maintain electrical neutrality. The special feature in ceramics is therefore the movement of charge and the requirement for overall electrical neutrality. We can thus apply a voltage to the system and cause an electric or ionic current to flow. As in other systems, the slower moving species will control the rate of the reaction. 

In the particular case of a metal semiconductor system, whose energy diagram is given in Figure 6.33, the contact potential difference is obtained using the relation ... 

Table 1. List of metal/semiconductor systems for which the data are present in this chapter (marked by bullets) with the references to the appropriate general tables, (hkl) denotes the high-Miller-index surfaces.

In a metal-semiconductor system, when the metal and semiconductor come into contact, a Schottky junction forms. This band deformation enhances the separation... 

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