Page 65 - Microsensors, MEMS and Smart Devices - Gardner Varadhan and Awadelkarim
P. 65
46 MEMS MATERIALS AND THEIR PREPARATION
Figure 3.11 Plane identification in terms of the intercepts on the x, y, and z axes
Figure 3.12 Unit cell of a simple cubic (SC) crystal lattice structure
The following subsections describe some of the common crystal structures encountered
and those that are used to describe MEMS materials.
3.1.3.1 Cubic structures
The geometric shape of the unit cell in cubic structures is a cube. If a single atom or a
group of atoms are placed at the corners of the cube, this constitutes a simple cubic (SC)
crystal (Figure 3.12). Each one of the cube corners constitutes a site, or a lattice point,
which can be occupied by one building block (an atom or a group of atoms). Because
each corner of a given cube is shared by other seven cubes, it turns out that each unit
cell contains, in essence, one site or one lattice point in SC structure. In addition, in an
