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.

• Radiation Detection

  • Different types of radiation detectors exist ; gaseous ionization detectors, semiconductor detectors, and scintillation detectors are the most common.
  • A semiconductor detector uses a semiconductor (usually silicon or germanium) to detect traversing charged particles or the absorption of photons.
  • When these detectors' sensitive structures are based on single diodes, they are called semiconductor diode detectors.
  • When they contain many diodes with different functions, the more general term "semiconductor detector" is used.
  • Semiconductor detectors have had various applications in recent decades, in particular in gamma and x-ray spectrometry and as particle detectors.

• Dependence of Resistance on Temperature

  • Note also that α is negative for semiconductors, meaning that their resistivity decreases with increasing temperature.
  • This property of decreasing ρ with temperature is also related to the type and amount of impurities present in the semiconductors.
  • One of the most common is the thermistor, a semiconductor crystal with a strong temperature dependence, the resistance of which is measured to obtain its temperature.

• 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

• Solutions to Exercises in Chapter 4

  • P(H or G) = P(H) + P(G) − P(H and G) = 0.26 + 0.43 − 0.14 = 0.55
  • P(J or K) = P(J) + P(K) − P(J and K); 0.45 = 0.18 + 0.37 − P(J and K) ; solve to find P(J and K) = 0.10
  • P(Type O or Rh − ) = P(Type O) + P(Rh − ) − P(Type O and Rh − ) 0.52 = 0.43 + 0.15 − P(Type O and Rh − ); solve to find P(Type O and Rh − ) = 0.06; 6% of people have type O Rh − blood
  • P( NOT (Type O and Rh − ) ) = 1 − P(Type O and Rh − ) = 1 − 0.06 = 0.94; 94% of people do not have type O Rh − blood
  • P(R or F) = P(R) + P(F) − P(R and F) = 0.72 + 0.46 − 0.32 = 0.86

• 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.

• Lasers

  • There are many types of lasers depending on the gain media and mode of operation .
  • Gas and semiconductors are commonly used gain media.
  • The most common type of laser uses feedback from an optical cavity--a pair of highly reflective mirrors on either end of the gain medium.
  • Laser types with distinct laser lines are shown above the wavelength bar, while below are shown lasers that can emit in a wavelength range.
  • The height of the lines and bars gives an indication of the maximal power/pulse energy commercially available, while the color codifies the type of laser material.

• Comparing Two Independent Population Proportions

  • ${ P }_{ A }^{ ' }-{ P }_{ B }^{ ' }$
  • That is, $H_0: p_A = p_B$.
  • $\displaystyle z=\frac { { (p }_{ A }^{ ' }-{ p }_{ B }^{ ' })-({ p }_{ A }-{ p }_{ B }) }{ \sqrt { { p }_{ c }\cdot (1-{ p }_{ c })\cdot \left( \frac { 1 }{ { n }_{ A } } +\frac { 1 }{ { n }_{ B } } \right) } }$.
  • Two types of medication for hives are being tested to determine if there is a difference in the proportions of adult patient reactions. 20 out of a random sample of 200 adults given medication $A$ still had hives 30 minutes after taking the medication. 12 out of another random sample of 200 adults given medication $B$ still had hives 30 minutes after taking the medication.
  • ${ P }_{ A }^{ ' }-{ P }_{ B }^{ ' }$

• The Hall Effect

  • For a metal containing only one type of charge carrier (electrons), the Hall voltage (VH) can be calculated as a factor of current (I), magnetic field (B), thickness of the conductor plate (t), and charge carrier density (n) of the carrier electrons:
  • The Hall effect is a rather ubiquitous phenomenon in physics, and appears not only in conductors, but semiconductors, ionized gases, and in quantum spin among other applications.
  • Express Hall voltage for a a metal containing only one type of charge carriers