Additional Materials

1
Additional Materials
2
Crystal Growth(Making of a single crystal)

• Q What is single crystal?
• A Single crystal All the basic units
  (atoms/molecules) are arranged in a uniform
  manner throughout the material.
• Q How a single crystal can be formed?
• A Two ways
• 1. Natural crystal e.g. Dimond, Jade, Ruby etc
  They are formed by millions of years under the
  earth pressure and temperature.
• 2. Man made crystal Silicon (Si), Germanium
  (Ge) and many other technologically important
  materials as well as engineered quantum
  structures and devices.
• Making of such man-made crystal is called
  crystal growth.
• Crystal can be formed by condensing liquid or gas
  phases of the materials.

3
Some Crystal Growth Techniques

• There are many crystal growth techniques. Here
  are a few widely used techniques
• CVT Chemical Vapor Transport (basic technique
  used in labs)
• MBE Molecular Beam Epitaxy (fine quantum
  structures can be formed and mainly used in the
  labs)
• MOCVD Metallo Organic Chemical Vapor Deposition

4
Crystal Growth (CVT)
5
ZnTe Crystal
6
ZnS
7
ZnS
8
Electron Diffraction SpotsZnS
9
Electron DiffractionZnTe
10
ZnTe X-Ray Diffraction