exist is for valence electrons to "leap" into the conduction band with theEnoiteouQuestion 5pplication of sufficient energy, legving a hole, or vacancy, behind in thevalence band:Valence electron leapinginto conduction bandConduction bandvalence bandWith sufficient thermal energy, these electron-hole pairs will form spontaneously.Af room temperature, however, this activity is slight.we may greatly enhance charge carrier formation by adding specific impuritiesto the semiconducting material. The energy states of atoms having differentelectron configurations do not precisely "blend" with the electron bands of theparent semiconductor crystal, causing additional energy levels to form.Some types of impurities will cause extra donor electrons to lurk just beneath themain conduction band of the crystal. These types of impurities are calledpentavalent, because they have 5 valence electrons per atom rather than 4 asthe parent substance typically possesses:Doped with a "pentavalent" impurityConduction band"Donor electronsValence bandOther types of impurities will cause vacant electron levels (acceptor "holes") toform just above the main valence band of the crystal. These types of impuritiesgre called triívalent, because they have 3 valence electrons per atom instead of4: Doped with a "trivalent" impurityConduction band"Acceptor" holesValence bandA. Compare the ease of forming free (conduction-band) electrons in asemiconductor material having lots of "donor" electrons, against that ofan intrinsic (pure) semiconductor material. Which type of material will bemore electrically conductive?B. Likewise, compare the ease of forming valence-band holes in asemiconductor material having lots of "acceptor" holes, against that of anintrinsic (pure) semiconductor material. Which type of material will bemore electrically conductive?

Given : The circuit showing the intrinsic conductor. We have to compare intrinsic conductor with…

Doped with a "trivalent" impurity Conduction band "Acceptor" holes Valence band A. Compare the ease of forming free (conduction-band) electrons in a semiconductor material having lots of "donor" electrons, against that of an intrinsic (pure) semiconductor material. Which type of material will be more electrically conductive? B. Likewise, compare the ease of forming valence-band holes in a semiconductor material having lots of "acceptor" holes, against that of an intrinsic (pure) semiconductor material. Which type of material will be more electrically conductive?

Doped with a "trivalent" impurity Conduction band "Acceptor" holes Valence band A. Compare the ease of forming free (conduction-band) electrons in a semiconductor material having lots of "donor" electrons, against that of an intrinsic (pure) semiconductor material. Which type of material will be more electrically conductive? B. Likewise, compare the ease of forming valence-band holes in a semiconductor material having lots of "acceptor" holes, against that of an intrinsic (pure) semiconductor material. Which type of material will be more electrically conductive?

Modern Physics

3rd Edition

ISBN:9781111794378

Author:Raymond A. Serway, Clement J. Moses, Curt A. Moyer

Publisher:Raymond A. Serway, Clement J. Moses, Curt A. Moyer

Chapter12: The Solid State

Section: Chapter Questions

Problem 18P

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