Semiconductor materials are a class of electronic materials that have semiconductor properties and are used to make semiconductor devices.
Characteristics of semiconductor materials
Semiconductor materials usually have a certain forbidden bandwidth and their electrical properties are susceptible to external conditions (e.g., light, temperature, etc.). Different conductive types of materials are prepared by doping with specific impurities. Impurities (especially heavy metal fast diffusion impurities and deep energy level impurities) have a particularly strong influence on the material properties. Therefore, semiconductor materials should be of high purity, which requires not only that the raw materials used to produce semiconductor materials should be of considerable purity, but also an ultra-clean production environment, with a view to minimizing impurity contamination in the production process. Most of the semiconductor materials are crystals, and semiconductor devices have high requirements for the crystal integrity of the materials. In addition, there are strict requirements for the uniformity of the various electrical parameters of the material.
Classification of semiconductor materials
Semiconductor materials can be classified according to their chemical composition, and amorphous and liquid semiconductors with special structures and properties are classified as a separate category. According to this classification method, semiconductor materials can be divided into elemental semiconductors, inorganic compound semiconductors, organic compound semiconductors, and amorphous and liquid semiconductors.
There are 11 kinds of semiconducting substances distributed in Group IIIA to Group IVA of the periodic table of elements. Among these 11 element semiconductors, only three elements, namely, Ge, Si, and Se, have been utilized. Ge and Si are still the two most widely used materials among all semiconductor materials.
Inorganic compound semiconductors
Inorganic compound semiconductors can be sub-divided into binary systems, ternary systems, and quaternary systems.
The binary system includes:
The ternary system includes:
Organic compound semiconductors
There are dozens of known organic semiconductors, such as naphthalene, anthracene, polyacrylonitrile, phthalocyanine, and some aromatic compounds.
Amorphous and liquid semiconductors
The biggest difference between this type of semiconductor and crystalline semiconductor is that it does not have a strictly periodic crystal structure.
What are the common semiconductor materials?