What is the difference between Schottky contact and ohmic contact?
An ohmic contact is a contact between two metals or conductors it follows ohm’s law and conducts in all directions. A Schottky contact is junction between metal & semiconductor it is a rectifying junction & has a nonlinear characteristic.
What is the difference between ohmic contact and rectifying contact?
A contact between metal and silicon can be rectifying or ohmic. The most commonly used rectifying contact is the Schottky barrier diode (SBD). A contact is said to be ohmic, i.e., non-rectifying, if it exhibits negligible resistance to current in both voltage polarities.
What is meant by an ohmic contact?
The Ohmic contact is a low resistance junction (non-rectifying) provides current conduction from metal to semiconductor and vice versa. Theoretically speaking the current should increase/ decrease linearly with the applied voltage.
What are Ohmic and non ohmic contact?
1.Ohmic resistors are the resistors which obey ohms law. Non ohmic resistors are those which do not obey ohms law. 2.In ohmic resistors current is directly proportional to voltage. In non ohmic resistors there is no linear relationship.
How do you know if its Schottky or ohmic?
Overall, for a metal and an n-type semiconductor, a rectifying Schottky contact is formed when ΦM>ΦS, and an Ohmic contact is formed when ΦM<ΦS. Similarly, for a metal and an p-type semiconductor, the MS contact will be rectifying Schottky when ΦM<ΦS, and Ohmic contact when ΦM>ΦS.
What are called Schottky and ohmic metal semiconductor junction?
The rectifying metal–semiconductor junction forms a Schottky barrier, making a device known as a Schottky diode, while the non-rectifying junction is called an ohmic contact. (In contrast, a rectifying semiconductor–semiconductor junction, the most common semiconductor device today, is known as a p–n junction.)
What is Schottky contact with reference to metal semiconductor junction?
A Schottky barrier refers to a metal-semiconductor contact having a large barrier height (i.e. and low doping concentration that is less than the density of states in the conduction band or valence band. The potential barrier between the metal and the semiconductor can be identified on an energy band diagram.
What is the purpose of Schottky diode?
Schottky diodes are used for their low turn-on voltage, fast recovery time and low-loss energy at higher frequencies. These characteristics make Schottky diodes capable of rectifying a current by facilitating a quick transition from conducting to blocking state.
What is the difference between ohmic material and non ohmic material?
Ohmic conductors are the conductors that follow Ohm’s law that is their resistance remains the same on changing the current and voltage. Non-ohmic conductors are those that do not follow ohm’s law which means that their resistance changes with changing current and voltage.
What are ohmic and non ohmic devices give examples?
Devices that follow Ohm’s law is known as ohmic devices. Examples: resistor and wire. Devices that do not follow Ohm’s law is known as non-ohmic devices. Examples: vacuum tube and thermistors.