Impurities na Donor da Acceptor a Semiconducto

Takaitaccen Doping

Doping shi na iya aiki na hada da abubuwa masu kwallon semiconductors don canza mafarin mutanen da suke.

Abubuwan Donor

Abubuwan donor suna cikin atoms da dukkan nan pentavalent da ake hada a semiconductors, wanda ke bayar electrons mai kyau, wanda ke gina semiconductors na n-type.

Semiconductor na N-Type

Idan abubuwan n-type ko donor suna hada a semiconductor, yana ci gaba haguwar energy gap a cikin tashar lattice. Abubuwan donor suna bayar sabon energy levels kadan da conduction band. Wanannan levels suna da ma'ana saboda abubuwan impurity suna zama da sauransu da ba su tabbas ba. A germanium, haguwar energy gap yana da 0.01 eV, kuma a silicon, yana da 0.05 eV a faduwar jiki. Saboda haka, a faduwar jiki, electron na biyu daga abubuwan donor yana zaune a conduction band. Yawan electrons mai kyau yana haifar da holes.

Yawan holes zuwa yanayin volume a cikin semiconductor na n-type yana da tsawon da ya fi kai zuwa yanayin volume a cikin intrinsic semiconductor a matsayin jiki. Wannan yana faruwa saboda electrons mai kyau, kuma zai haifar da recombination rate na electron-hole pairs inda ya fi kai zuwa pure ko intrinsic semiconductor.

Semiconductor na P-Type

Idan bata pentavalent impurity, trivalent impurity yana hada a intrinsic semiconductor, yana haifar da holes mai kyau a crystal. Idan trivalent impurity yana hada a cikin semiconductor crystal, abubuwan trivalent zai koyar da wasu tetravalent semiconductor atoms. Samari (3) valance electrons daga atom na trivalent impurity zai yi bond da samun neighborhood semiconductor atoms. Saboda haka, zai kasance lack of an electron a cikin bond na fourth neighboring semiconductor atom wanda yake bayar hole zuwa crystal. Saboda abubuwan trivalent impurities suna bayar excess holes zuwa semiconductor crystal, kuma holes wadannan zai iya accept electrons, wannan abubuwan impurities suna cika da acceptor impurities. Idan holes suna cikin charge mai karfi, wannan abubuwan impurities suna cika da positive – type ko p type impurities kuma semiconductor da p type impurities ana kiranta p-type semiconductor.

Idan trivalent impurities suna hada a cikin semiconductor, yana haifar da discrete energy level kadan da valence band. Tsawon gap kadan da valence band da wannan sabon energy level yana ba electrons da kyau a zuwa level mai yawa da energy mai kalmomi. Idan electron yana zuwa wannan sabon level, yana ba vacancy, ko hole, a cikin valence band.

Idan ake hada n-type impurity zuwa semiconductor, zai haifar da excess electron a cikin crystal amma ba zai cewa ba zai haifar da hole. Saboda nature intrinsic na semiconductor a faduwar jiki, zai da some electron-holes pairs a cikin semiconductor. Saboda hada n-type impurities, electrons zai haifar da electron-hole pairs kuma yana haifar da number of holes reduced excess recombination for excess electrons. Saboda haka, total number of negative charge carriers ko free electrons zai haifar da that of holes a cikin n-type semiconductor. Saboda haka a n-type semiconductor, electrons suna cika da majority charge carriers kuma poles suna cika da minority charge carriers. Kamar haka a p-type semiconductor, holes suna cika da majority charge carriers kuma electrons suna cika da minority charge carriers.

Abubuwan Acceptor

Abubuwan acceptor suna cikin atoms da dukkan nan trivalent da ake hada a semiconductors, wanda ke bayar excess holes, wanda ke gina semiconductors na p-type.