semiconductor
Semi Conductors
A substance with electrical properties between those of a good conductor and those of a good insulator.They often produced by dopping.
Intrinsic Semi Conductors
Intrinsic semiconductors are composed of only one kind of material. Silicon and germanium are two examples. They are also called "undoped semiconductors" or "i-type semiconductors".
Extrinsic Semi Conductors
Extrinsic semiconductors are made of intrinsic semiconductors that have had other substances added to them to alter their properties (they have been doped with another element).
There are two types of extrinsic semiconductors: p-type (p for positive: a hole has been added through doping with a group-III element) and n-type (n for negative: an extra electron has been added through doping with a group-V element)
N-Type Semi Conductor
N-type semiconductors are a type of extrinsic semiconductor in which the dopant atoms (donors) are capable of providing extra conduction electrons to the host material (e.g. phosphorus in silicon). This creates an excess of negative (n-type) electron charge carriers.
P-Type Semiconductors
A p-type (p for "positive") semiconductor is created by adding a certain type of atom (acceptor) to the semiconductor in order to increase the number of free charge carriers (in this case positive holes).
Band Theory
Metals and semiconductors have a unique property that separates them from non-conductive insulators. In metals and insulators, the difference between energy orbitals are so small that electrons can be excited from lower energy orbitals to higher energy levels. These small orbital energy differences are referred to as bands. Unlike the discrete energy levels that you are taught about in beginning chemistry, these bands are so close together in energy that it takes a very small amount of energy to promote electrons to these higher band levels. The higher energy level that the valence electrons can be excited to is referred to as the
A substance with electrical properties between those of a good conductor and those of a good insulator.They often produced by dopping.
Intrinsic Semi Conductors
Intrinsic semiconductors are composed of only one kind of material. Silicon and germanium are two examples. They are also called "undoped semiconductors" or "i-type semiconductors".
Extrinsic Semi Conductors
Extrinsic semiconductors are made of intrinsic semiconductors that have had other substances added to them to alter their properties (they have been doped with another element).
There are two types of extrinsic semiconductors: p-type (p for positive: a hole has been added through doping with a group-III element) and n-type (n for negative: an extra electron has been added through doping with a group-V element)
N-Type Semi Conductor
N-type semiconductors are a type of extrinsic semiconductor in which the dopant atoms (donors) are capable of providing extra conduction electrons to the host material (e.g. phosphorus in silicon). This creates an excess of negative (n-type) electron charge carriers.
P-Type Semiconductors
A p-type (p for "positive") semiconductor is created by adding a certain type of atom (acceptor) to the semiconductor in order to increase the number of free charge carriers (in this case positive holes).
Band Theory
Metals and semiconductors have a unique property that separates them from non-conductive insulators. In metals and insulators, the difference between energy orbitals are so small that electrons can be excited from lower energy orbitals to higher energy levels. These small orbital energy differences are referred to as bands. Unlike the discrete energy levels that you are taught about in beginning chemistry, these bands are so close together in energy that it takes a very small amount of energy to promote electrons to these higher band levels. The higher energy level that the valence electrons can be excited to is referred to as the