Diamond chip

[seminar class]

PRESENTED BY :
S. VENKATESH
JEET SINHA ROY

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Introduction
 Electronics without silicon is unbelievable.
 Disadvantages when used in power electronics application, such as:
1) bulk in size
2) slow operating speed, etc.
 Pure Silicon and Germanium are semiconductors in normal temperature.
 In earlier days they were used widely for manufacturing of electronic components.
 Research people found that carbon has more advantages than silicon.
 Using carbon as the manufacturing material, we can achieve smaller, faster and stronger chips.
What is diamond chip?
 In a single definition, Diamond Chip or Carbon Chip is an Electronic Chip manufactured on a diamond structure Carbon wafer
How is it possible ?
 Diamond structural carbon is non conducting in nature.
 To make it conducting, doping process is performed.
Boron-- as the p-type.
Nitrogen--as the n-type.
invention
Developed by Nippon Telegraph and Telephone Corporation (NTT), Japan, 1991.
A diamond semiconductor operates on a 81 GHz frequency, and is more than twice the speed of earlier devices.
Some facts…
 Carbon is not a semiconductor.
 Some of the carbon allotropes acts as semiconductor.
 The functionality of graphene.
The functionality of nanotubes.
 Graphene.
 What is carbon nanotube?
 Types of nanotubes
 How Nanotubes act as semiconductors?
Why the name DIAMOND CHIP?
 Lonsdaleite is an sp3 bondage allotropic form of carbon i.e. 3-dimentional CNT.
 Crystal structure of Lonsdaleite looks exactly like diamond.
Properties of CNT
 Properties
 1 Strength
 2 Hardness
 3 Electrical
 4 Thermal
 5 One-dimensional transport
 HARDNESS :
 It can withstand a pressure up to 24GPa without deformation.
 STRENGTH :
 Carbon nanotubes are the strongest and stiffest materials yet discovered in terms of tensile strength and elastic modulus respectively.
 ELECTRICAL :
 High electrical conductivity (10-6 ohm).
 Do not suffer from electro migration or atomic diffusion and thus can carry high current densities (107 -109 A/cm2 ),which is 1000 times that of copper.
 Both metal and semiconductor can be formed.
 Properties…
 THERMAL :
 The temperature stability of carbon nanotubes is estimated to be up to 2800 °C in vacuum and about 750 °C in air.
 ONE DIMENTIONAL TRANSPORT :
 Because of the nanoscale dimensions, electrons propagate only along the tube's axis.
 Carbon nanotubes are frequently referred to as “one-dimensional”
CNT can form ideal diode.
 We placed two separate gates underneath a single-walled nanotube
 Biasing one gate with a negative voltage and the other with a positive voltage, a p-n junction ideal diode is formed.
 A brief idea about carbon transistors
 Much smaller components are possible.
 Conducts electricity faster as electrons travels through straight line without scattering.
 Ultimately we get faster and more efficient electronic component.
 How nanotubes are useful in digital logic?
 Simple inverter device consists of a nanotube FET and a large bias resistance: which converts a high input voltage to a low one –i.e., "one" to "zero" - and vice versa.
 By adding an extra FET in parallel, the researchers made a NOR gate. This device needs two "zero" inputs to give a "one" output, or two "ones" to give a "zero”.
ADVANTAGES
 Smaller components are possible.
 It works at higher temperature.
 Faster than silicon chips.
 Larger power handling capacity.
 Carbon nanotube Applications
 Information and Communications,
 Materials and Manufacturing,
 Biomedical,
 Energy and Environmental,
 Transportation
 Consumer goods.
LIMITATIONS
 Much more expensive than silicon.
 Doping process is very hard to perform due to the diamond structure , than in silicon.
Conclusion
Thus diamond chip replaces the need of silicon in every aspect in future generation.