Energy band in semiconductors

S2.3 Point Defects and Energy Bands in Semiconductors and Insulators... 

Long, D. (1968), Energy Bands in Semiconductors, Interscience, New York, p. 111. 

What is the dependence of the gap between the energy bands in semiconductor nanocrystals on its size ... 

Figure 1. Schematic illustration of how energy bands in semiconductors evolve from discrete atomic states for the specific example of silicon.

This is a classic work, containing a wealth of physical insight into the origin and nature of energy bands in semiconductors. 

Charging of the surface accompanying adsorption process and resulting in the change of the energy profile of the bottom of the conductivity band and, naturally, the ceiling of the valence band in semiconductors... 

Figure 6.14 Schematic illustration of energy bands in a p-type, extrinsic semiconductor. From Z. Jastrzebski The Nature and Properties of Engineering Materials, 2nd ed. Copyright 1976 by John Wiley Sons, Inc. This material is used by permission of John WUey Sons, Inc.

The simple picture of the MOS capacitor presented in the last section is complicated by two factors, work function differences between the metal and semiconductor and excess charge in the oxide. The difference in work functions, the energies required to remove an electron from a metal or semiconductor, is 0ms = —25 meV for an aluminum metal plate over a 50-nm thermally grown oxide on -type silicon with n = 1016 cm-3. This work function difference leads to a misalignment of energy bands in the metal and semiconductor which has to be compensated by a variation of the energy band with distance. When there is no misalignment the flat-band condition results. 

The energy difference between the valence and conduction bands in semiconductors. It is related to the absorption edge of the semiconductor. 

Understanding the behavior of a MOS capacitor is useful in understanding the operation of a MOS transistor. When a negative voltage is applied to the conductor or metal, the energy bands in the p-type semiconductor... 

A. A. Levin, Introduction to the Quantum Theory of Solids. Chemical Bonding and Structure of Energy Bands in Tetrahedral Semiconductors, Khimiya, Moscow, 1974. 

In Chapter 3 we gave a preliminary discussion of the energy bands in terms of the simple LCAO theory, and illustrated, in Fig. 3-7, the form of more accurately determined energy bands. For most of the studies made in this text, that description will be sufficient. However, the bands are of some interest in their own right and are important to the understanding of the electronic properties of semiconductors, and a consideration of them increases one s understanding of the electronic structure of covalent solids. In this chapter, therefore, we shall look at a more extensive set of accurate bands and at their interpretation in terms of the con-... 

Charge transfer between energy states in semiconductor and in the redox system only occurs when there is a sufficient overlap of occupied and empty states. The actual currents across the interface can be derived for conduction or valence band processes by taking into account the equilibrium conditions, where and jy" = j,- = jy, and also 115 = 0 and p, = p . In the case... 

Figure 3.68. Sketch of energy levels in semiconductors. The level of a donor electron is just below (the lower side of) the conduction band, that of an acceptor electron just above (the upper side of) the valence band. Dashed Fermi levels. The picture applies to a strongly doped semiconductor for low degrees of doping, the Up and Uy bands must be replaced by discrete donor-acceptor pairs.

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