Why is Carbon the first element in the group is not a semi conductor though all the other elements are
What exactly is the valency of Carbon thenlalSimply saying, there is nothing to carry the current. No free electrons or no holes. Eith valency 4, every electrons in the outermost orbit take part in the bonding.
In Si & even in Ge, all e- takes part in formation of covalent bond.lalSimply saying, there is nothing to carry the current. No free electrons or no holes. Eith valency 4, every electrons in the outermost orbit take part in the bonding.
But due to temperature(heat) those bonds are easily broken & e- are produced, resulting in flow of e-.
Current in crystal is practically impossible.
Also C6, so electronic configuration is 1s2 2s2 2p2, so more energy is required to remove an e- from the bond.The amount of energy required is not available at room temperature.
So, one of the most essential property of semiconductor is lacking.
But in any cost we use crystalline Silicon but as troll said omit the crystalline carbon for the reason of higher ionisation energylalCarbon as graphite is but a semiconductor, diamond is not. That means, troll, as u said the crystaline form cant conduct. Right?
Because C-C are tightly bounded.
But doping can change result (I am not sure though)
SiC is one eg where C is doping element in Si.
Boss SiC is a compound used as an insulator and not as a semi conductor I am not sure either but Silicon carbide is better known for its high temperature resistance and high insulating propertiesTroll_So_HardCrystalline Carbon cant conduct.
Because C-C are tightly bounded.
But doping can change result (I am not syre though)
SiC is one eg where C is doping element in Si.
It is also used in LEDs 'cause it emits "blue" light.
To conclude,
Carbon -> Require lots of energy to work.
Silicon -> Mid range, not to high, not to low.
Germanium -> Very low.
The first and last both are not acceptable. The only reason because Germanium is used as its properties can be controlled, but in case of carbon as TSH mentioned, it just goes to form a crystalline structure.
the latest form of carbon which is known as graphene and it is very superior than other convention semiconductors.
sowmiya vdelectricity can conduct through carbon but it has no resistance and all electrical energy will be wasted in the form of heat and it forms crystalline structure(diamond).
the latest form of carbon which is known as graphene and it is very superior than other convention semiconductors.
link...
https://www.sfgate.com/business/article/Graphene-could-create-faster-semiconductors-2334444.php
Hey friend you are forgetting some thing very important if the conduction is very high then why is it not out in the market now ?sowmiya vdgraphene conducts electricity 30 times faster than silicon!!but the use of graphene as semiconductor in replacement with silicon is still under research....
link...
https://www.sfgate.com/business/article/Graphene-could-create-faster-semiconductors-2334444.php
The reason is simple Si and Ge SiC SiAsP all are dependent on the atmospheric temperature only this makes them more predictable in their responses to a great extent the effect of external forces are absent in them
But the Graphene model as far as I know has higher conductivity but poorer stability in real world It is temperature dependent but more dependent on other external forces acting on the crystal due to piezo electric nature.This implies more stability concern extra stabilizers are needed for effective operation
Totally inter-related with what I said. What is providing voltage? Its giving external energy. What dies temperature do? It gives external energy.jeffrey samuelthe Ge threshold also pays a role of it not being popular if my calculations are right the presence of d subshell has brought the break over voltage from over 8 V in C to lesser than 1 V in Si and .3 V in Ge
Why Ge starts conduction at room temperature? Evident from neglibile threshold required i.e. 0.3 v.
Thats the reason I have writen energy to genralize it. It could be voltage or temperature.
so sometimes carbon is the influence of temperature behave as insulator where as some times carbon works as semiconductor. So that's why we don't consider carbon as semiconductor material.
I think that carbon does have some semiconductor properties, but it needs lot of energy to work like one. Carbon has no free electrons available, so it will never conduct electricity.
For an element like carbon to be considered as a semiconductor it needs to have a certain energy gap. According to theory it needs to be between 0.6 eV to 3.4 eV.
Since carbon falls in the higher energy gap category (which is 5.5eV), it will not be called a semiconductor. Hope this makes sense. ?
Carbon is a non-metal, and non-metals are poor conductors of electricity because the bond structure is a "close-packed arrangement." Silicon and germanium which are also in Group IVA are semi-conductors and are classified as metalloids. Metalloids show properties of both metals and non-metals. The have low electrical conductivity compared to metals but conduct more than non-metals. This property makes them useful in small scale electronics.
The basic property of semiconductor is that its conductivity lies between coonductor and insulator. Silicon and Germanium are the two mostly used semiconductor elements.
Carbon due to its property of not controlling the conductivity not used. Si and Ge acts as the conductors adn insulator dependng up on the voltage levels supplied. There is a term called cut off voltage in the semiconductors which when crossed by the supplied input voltage the semiconductor acts as the Conductor and below the cut off voltage it acts as Insulator. The cut off voltage for Ge and Si are 0.3 and 0.7 respectively. Once the device is operated above these voltages it works as conductor and less than that acts as insulator. Carbon will not have this property to control the conductivity. A pure carbon can never be used as an insulator, hence cannot be used as a semiconductor.
Nope as i said C-C covalent bond forms crystal. (eg diamond)
Current in crystal is practically impossible.
Also C6, so electronic configuration is 1s2 2s2 2p2, so more energy is required to remove an e- from the bond.The amount of energy required is not available at room temperature.
So, one of the most essential property of semiconductor is lacking.
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