What are the total types of semiconductors

First of all, semiconductors refer to materials with conductivity between conductors and insulators. Common materials include silicon, germanium, silicon carbide, gallium nitride, etc. Generally speaking, semiconductors refer to semiconductor materials, while triodes and diodes are semiconductor devices. No matter which one is, there are many kinds of them. Let's talk about some common ones. There are three basic types of semiconductor materials: intrinsic semiconductor, P-type semiconductor and N-type semiconductor. Intrinsic semiconductor: The material is completely pure, free of impurities, and the lattice is complete. Because the internal covalent bond is intrinsically excited (electrons in some valence bands cross the forbidden band into the empty band, forming electrons and holes that can move freely under the external electric field), it conducts electricity. To understand the conductive properties of semiconductors, we must have such a concept of electron hole pairs. In simple terms, electronic conduction is the movement of free electrons (negatively charged), and hole conduction is the movement of electrons in covalent bonds to nearby holes, which is represented by the movement of holes (positively charged). N-type semiconductor: dope a certain amount of pentavalent element impurities (donor impurities) such as phosphorus into the intrinsic semiconductor. Since the number of the outermost electrons of the atom is more than that of silicon and other materials, an extra electron will be generated after the formation of a covalent bond. The excitation energy of this electron is far lower than that of the valence electrons. Therefore, the conduction of N-type semiconductor materials is mainly free electrons (there are still a few holes), and the materials are still electrically neutral in this process.