Page 54 - Semiconductor For Micro- and Nanotechnology An Introduction For Engineers

Elastic Properties: The Stressed Uniform Lattice
,
Table 2.2. The spherical harmonic functions Y (
l
Figure 3.9 in Chapter 3. m θφ) 2 , Also see Table 3.1 and
l m Plot l m Plot l m Plot l m Plot
0 0

1 0 1 1

2 0 2 1 2 2

3 0 3 1 3 2 3 3

4 0 4 1 4 2 4 3

that we associate with its valence electrons. The construction is illus-
trated in Figure 2.16.

The valence electron orbitals may overlap to form bonds between atoms.
The interpretation is straightforward: a valence electron’s orbital repre-
sents the probability distribution of finding that electron in a specific
region of space. In a first approximation, we let the orbitals simply over-
lap and allow them to interfere to form a new shared orbital. Bonding
takes place if the new configuration has a lower energy than the two sep-
arate atom orbitals. The new, shared, hybrid orbital gives the electrons of

Semiconductors for Micro and Nanosystem Technology 51