p-type semiconductor

Examples of p-type semiconductor in the following topics:

• Doping: Connectivity of Semiconductors

  • When we place p-type and n-type semiconductors in contact with one another, a p-n junction is formed. p-n junctions are basic components of most common electrical devices.
  • While semiconductors doped with either n-type dopants or p-type dopants are better conductors than intrinsic semiconductors, interesting properties emerge when p- and n-type semiconductors are combined to form a p-n junction.
  • Combining n-type and p-type semiconductors creates a system which has useful applications in modern electronics.
  • The p-n junction forms between juxtaposed p- and n-type semiconductors.
  • The free electrons from the n-type semiconductor combine with the holes in the p-type semiconductor near the junction.

• Semiconductors

  • There are two types of extrinsic semiconductors that result from doping: atoms that have an extra electron (n-type for negative, from group V, such as phosphorus) and atoms that have one fewer electron (p-type for positive, from group III, such as boron).
  • A p-type (p for "positive") semiconductor is created by adding a certain type of atom to the semiconductor in order to increase the number of free charge carriers.
  • The purpose of p-type doping is to create an abundance of holes.
  • Thus, holes are the majority carriers, while electrons become minority carriers in p-type materials.
  • Compare N-type and P-type semi-conductors, distinguishing them from semi-conductors and insulators using band theory.

• Electron Configurations and Magnetic Properties of Ions

  • The p block, on the right, contains common non-metals, such as chlorine and helium.
  • The s and p blocks make up the main-group elements, also known as representative elements.
  • In bulk materials, this same idea helps explain the peculiar properties of lasers and semiconductors.
  • This image is color-coded to show the s, p, d, and f blocks of the periodic table.
  • Predict the type of ions an element will form based on its position in the periodic table

• Trihalides: Boron-Halogen Compounds

  • The electronics industry uses boron tribromide as a boron source in pre-deposition processes for doping in the manufacture of semiconductors.
  • Boron (III) trifluoride structure, BF3, showing the "empty" boron p orbital in pi-type coordinate covalent bonds.

• Sulfur Compounds

  • These materials tend to be dark-colored semiconductors that are not readily attacked by water or even many acids.
  • The mineral galena (PbS) was the first demonstrated semiconductor.
  • In the most common type of industrial "curing" or hardening and strengthening of natural rubber, elemental sulfur is heated with the rubber until chemical reactions form disulfide bridges between isoprene units of the polymer.

• Elemental Boron

  • Elemental boron is used as a dopant in the semiconductor industry.
  • AI-2 is used by many types of bacteria as a signaling molecule mediating quorum sensing.

• Determining Atomic Structures by X-Ray Crystallography

  • Substances including inorganic salts and minerals, semiconductors, and organic and biological compounds can form crystals under suitable and specific conditions.
  • The best x-ray crystallographic structures are derived from the purest crystal samples, meaning samples that contain only molecules of one type and as few impurities as possible.

• Acid-Base Titrations

  • strong acid-weak base titration: methyl orange indicator the base is off the scale (e.g., pH > 13.5) and the acid has pH > 5.5: alizarine yellow indicator
  • the base is off the scale (e.g., pH > 13.5) and the acid has pH > 5.5: alizarine yellow indicator
  • the base is off the scale (e.g., pH > 13.5) and the acid has pH > 5.5: alizarine yellow indicator
  • the acid is off the scale (e.g., pH < 0.5) and the base has pH < 8.5: thymol blue indicator
  • You can determine the pH of a weak acid solution being titrated with a strong base solution at various points; these fall into four different categories: (1) initial pH; (2) pH before the equivalence point; (3) pH at the equivalence point; and (4) pH after the equivalence point.

• Weak Acid-Strong Base Titrations

  • A weak acid will react with a strong base to form a basic (pH > 7) solution.
  • The titration curve demonstrating the pH change during the titration of the strong base with a weak acid shows that at the beginning, the pH changes very slowly and gradually.
  • When the NaOH is in excess, the pH change is the same as in any system dominated by NaOH.
  • However, the pH at the equivalence point does not equal 7.
  • Distinguish a weak acid-strong base titration from other types of titrations.

• Covalent Crystals

  • It is found in a certain type of meteorite that is thought to originate outside of our solar system.
  • Its extreme hardness and ease of synthesis have led to a diversity of applications -- in cutting tools and abrasives, high-temperature semiconductors and other high-temperature applications, the manufacturing of specialty steels and jewelry, and many more.
  • Silicon carbide is an extremely rare mineral, and in nature is is mostly found in a certain type of meteorite.