It also covers almost all the classes of materials i.e. inorganic and organic compounds, elemental materials
as well as biological macromolecules. Many methods have been developed over the years for producing
large single crystals, whose size ranges from nanometer to micro scale [1]. The processes for the
production of most single crystal are difficult which requires a technical skill in the synthesis of materials,
growth, processing and characterization [2].
This invention relates to a crystal growth method adapted for use in the formation of semiconductor light-
emitting devices and more particularly, to a crystal growth method wherein selective crystal growth of a
nitride semiconductor is carried out [3].
The opposite of a single crystal is an amorphous structure where the atomic position is limited to short
range order only. In between the two extreme exists polycrystalline which is made up of a number of
smaller crystals known as crystallites and polycrystalline phases. Crystals have an atomic ordering that
persists throughout their bulk and without the presence of grain boundaries .The two principal scientific
pillars upon which the field of crystal growth depends are thermodynamics and kinetics. Thermodynamics
properties of a system describe how solid, liquid and gaseous phases behave with respect to state variables
such as pressure, temperature, and composition. Kinetics factors on the other hand, influence our ability
to produce a crystal at a desired growth rate and a degree of perfection and uniformity suited to the
intended application.
It is a challenging attempt to grow a high quality single crystal. Satisfactory size of crystal(from fiber
crystals with diameter of tens of micrometers up to crystalline ingots of blocks with volume up to 1 m
3
)
and faultlessness (free from precipitates, inclusions, and twins with good uniformity and low concentration
of dislocations) are required for research and practical implementation on microelectronic circuits, electro-
optic switches and modulators, solid-state lasers, light emitting diodes, sensors, and many other devices
[4–8].
Over the past century, a sound theoretical foundation has been built up through the efforts of different
scientists and engineers working in materials related fields such as chemistry, physics and crystallography.
Although remarkable progress has been made, the complex nature of the field and its change emphasis on
newer materials and structures keep providing a constant source of challenges to the understanding of
crystallization process.