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Why is resistivity of a semiconductor higher than that of a metal?
Wiki User
∙ 14y ago
Resistivity is the resistance, in ohms, between the opposite faces of a 1-metre-cube of a material.
For metals, resistivity is in the region of 0.0000001 ohm-metre. For semiconductors, it is much higher - it is in the region of 0.01 ohm-metres.
Wiki User
∙ 14y ago
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From copper and manganin which has higher resistance?
The question is actually wrong, they can both have the same resistance if configured differently, the real question should be which has a higher resistivity which is the electrical resistance found in a standard amount of each material. In this case Manganin has a higher resistivity than copper.
How intrinsic semiconductor can be made into extrinsic semiconductor?
at higher values of temperature the intrinsic carrier concentration become comparable to or greater than doping concentration in extrinsic semiconductors. thus majority and minority carrier concentration increases with increase in temperature and it behaves like intrinsic semiconductor.
Why schottky is called hot carrier diode?
Because the energy of electrons transfer from semiconductor to metal side have more energy than the fermi energy of electrons in metal side. That's why these are called hot carrier diodes
Why the energy level of P type semiconductor is higher than of N type semiconductor?
We know that electrons are the majority carriers in n type semiconductor and holes are the majority carriers in p type semiconductor. The conductivity of n type is more than p type semiconductor due to mobility of electrons is higher than that of holes.
Why the voltage drop across LED is around 2V instead of 0.7V?
the binary semiconductors used to make LEDs have forward bias voltages from 1.5V to 6V depending on color (1.5V for IR-red to 6V for blue-UV) because the bandgap voltage of the semiconductor is higher than silicon. This higher bandgap is where the photons generated get their energy from. germanium has a lower forward bias voltage of 0.2V because the bandgap voltage is lower. metal-semiconductor contacts, like point contact diodes and schottky barrier diodes, can have forward bias voltages under 0.1V
When a sample of germanium and silicon having same impurity density are kept at room temperature then resistivity of both?
Resistivity of silicon higher than that of germanium
From copper and manganin which has higher resistance?
The question is actually wrong, they can both have the same resistance if configured differently, the real question should be which has a higher resistivity which is the electrical resistance found in a standard amount of each material. In this case Manganin has a higher resistivity than copper.
How intrinsic semiconductor can be made into extrinsic semiconductor?
at higher values of temperature the intrinsic carrier concentration become comparable to or greater than doping concentration in extrinsic semiconductors. thus majority and minority carrier concentration increases with increase in temperature and it behaves like intrinsic semiconductor.
Do semiconductors contain many free electrons?
Relatively speaking, semiconductors have more free electrons than insulators but fewer than conductors. For example, silicon is a semiconductor, the intrinsic carrier concentration is about 1 x 1010 cm-3, at room temperature. A proxy for the electron concentration is resistivity. Comparison at room temperature below: aluminum (metal); resistivity ~ 2.7 x10-8 [Ω-m] silicon: > 130 [Ω-m], depending on purity insulator: > 1 x 1010 [Ω-m] Please see the related link too. =================================
What is difference between ohmic and rectifying contact?
A p-n junction (or a metal-semiconductor junction) with rectifying behaviour is an electronic device which allows a one-way only current flow (between the two semiconductor regions, or between the metal and the semiconductor). An ohmic contact in a metal-semiconductor junction is realized by lowering the potential barrier (allowing electrons to easily migrate into the metal) and by increasing the doping levels in the semiconductor (more than 10^18 cm^-3): this way the potential barrier, that should stop electrons from migrating into the semiconductor, is confined in a very small region making it possible for electrons with low energy to pass through it (tunneling effect). This means that in a ohmic contact current can flow both ways; such a device apparently works like a resistor with a low resistance, hence the "ohmic contact" name.
Why is a metal bat stronger than a wooden bat?
because metal is a higher quality
Why Magnesium metal is a better conductor than Sodium metal?
Because there are a higher amount of delocalised electrons.
Why schottky is called hot carrier diode?
Because the energy of electrons transfer from semiconductor to metal side have more energy than the fermi energy of electrons in metal side. That's why these are called hot carrier diodes
Why Alloys of metals have greater resistivity than their constituents?
Resistance is due to scattering of conduction electrons. A metallic crystal can be viewed simplistically as a periodic array of ions with a cloud of delocalised conduction elections. The electrons do not scatter of the ions themselves because the crystal is periodic. There are two significant causes of scattering: 1. scattering off vibrations of the atomic lattice (phonons). This contribution to the resistivity is proportional to temperature. 2. scattering off defects in the crystal. At low temperature, this is the cause of a finite 'residual resistivity'. The two terms add linearly Rtotal = R1(T) + R2 Cold working a metal will introduce defects and thus lead to an increase in R2. Conversely, annealling the metal at high temperature will remove defects and reduce the residual resistivity.
Which of these properties would be more likely to be associated with a metal than a nonmetal?
Examples: malleability, ductility, thermal conductivity, electrical resistivity, solid state, magnetism, high melting point, etc.
Why the energy level of P type semiconductor is higher than of N type semiconductor?
We know that electrons are the majority carriers in n type semiconductor and holes are the majority carriers in p type semiconductor. The conductivity of n type is more than p type semiconductor due to mobility of electrons is higher than that of holes.
Does alumina become conductive at high temperatures?
Alumina is a good electrical insulator; at high temperatures the resistivity is smaller than the resistivity at room temperature.
