CHEM01200604009 Sreejith Kaniyankandy - Homi Bhabha ...

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1.2. Physics of Semiconductors
1.2.1. Introduction
Before describing how dimensionality influences electronic structure it is necessary to
understand the basics of semiconductors. Semiconductors by virtue of the electronic structure
are materials which has forbidden zone between valence and conduction band. The
difference in the energy between the valence band maxima and conduction band minima is
called as band gap. The evolution of the electronic structure depends on interaction between
atoms or ions comprising crystal lattice. This interaction eventually leads to overlapping
electron clouds between adjacent lattice atoms which in turn splits the energy levels as shown
in Fig.1.1.
Figure 1. 1. Schematic of Energy Band in a typical semiconductor versus bond length