Electric tam sim no nyob rau hauv lub semiconductors

Electric tam sim no nyob rau hauv semiconductors - yog hais zog ntawm qhov thiab electrons, uas yog los ntawm cov hluav taws xob field.

Raws li ib tug tshwm sim ntawm thwmsim, nws twb pom hais tias cov hluav taws xob tam sim no nyob rau hauv semiconductors yog tsis koom nrog lub hloov lwm lub tsev ntawm qhov teeb meem - lawv tsis koom nrog tej tshuaj hloov. Yog li, lub muaj, electrons yuav suav hais tias nyob rau hauv semiconductors.

Lub peev xwm ntawm cov ntaub ntawv uas tsim nyob rau hauv nws ib tug hluav taws xob tam sim no yuav txiav txim los ntawm cov kev conductivity. Los ntawm qhov ntsuas no conductors nyob ib nrab txoj hauj lwm ntawm lub conductors thiab insulators. Semiconductors - cov no yog cov sib txawv ntawm cov minerals, tej co, hlau sulfides, thiab lwm yam Electric tam sim no nyob rau hauv semiconductors tshwm sim los ntawm lub concentration ntawm free electrons uas yuav txav mus directionally nyob rau hauv ib yam khoom. Muab piv co thiab conductors, tej zaum nws yuav tsum tau muab sau hais tias muaj yog ib tug sib txawv ntawm cov kub cawv rau lawv cov conductivity. Ib qho kev nce nyob rau hauv kub ua rau ib tug txo nyob rau hauv lub conductivity ntawm hlau. Nyob rau hauv semiconductors lub conduction tus nqi nce. Yog hais tias ib tug semiconductor kub nce, lub suab ntawm free electrons yuav muaj ntau erratic. Qhov no yog vim ib qho kev nce rau hauv lub xov tooj ntawm collisions. Txawm li cas los, nyob rau hauv semiconductors nyob rau hauv kev sib piv nrog hlau, nws yog tshuam ntau zog zaub ceev ntawm free electrons. Tej yam zoo muaj cov lus rov ntxim rau cov conductivity: qhov ntau collisions, tus me tus conductivity, ntau dua qhov lub concentration, ntau dua qhov nws yog. Nyob rau hauv cov hlau, muaj yog tsis muaj dependence ntawm qhov kub thiab lub concentration ntawm free electrons, yog li ntawd ib tug kev hloov nyob rau hauv conductivity nrog ua kub xwb dua li qub tau ntawm ib tug kom tsab ntawv tsa suab ntawm free electrons. Raws li rau lub semiconductor, cov zaub nyhuv zuj zus lub concentration dua. Yog li, qhov kub thiab txias sawv yuav muaj ntau dua, ntau dua qhov lub conductivity.

Muaj yog ib tug kev sib raug zoo ntawm lub zog ntawm xwb muaj thiab ib lub sij hawm xws li hluav taws xob tam sim no nyob rau hauv semiconductors. Nyob rau hauv semiconductors, them nqa tsiag ntawv los ntawm cov tsos ntawm ntau yam, cov uas yog ib qho tseem ceeb kub thiab kev coj dawb huv ntawm cov khoom. Purity semiconductors raug muab faib ua extrinsic thiab tus kheej.

Raws li rau nws tus kheej neeg xyuas pib, cov nyhuv ntawm impurities ntawm ib tug tej yam kub tej zaum yuav tsis tseem ceeb rau lawv. Txij li thaum lub band kis ntawm semiconductors yog tsawg tsawg, nyob rau hauv ib tug tseem ceeb semiconductor, thaum kub nce mus txog tsis pes tsawg, yog ib tug ua kom tiav filling ntawm lub valence electrons. Tab sis lub conduction qhab yog kiag li free: muaj yog tsis muaj hluav taws xob conductivity, thiab nws tso cai raws li ib qho zoo tagnrho insulator. Nyob rau lwm lub kub, muaj ib tug tau hais tias lub thermal hloov mus hloov los ntawm cov kev electrons yuav kov yeej lub peev xwm barrier thiab tshwm sim nyob rau hauv lub conduction band.

Thomson nyhuv

Lub hauv paus ntsiab lus ntawm thermoelectric Thomson nyhuv thaum ib tug hluav taws xob tam sim no nyob rau hauv semiconductors, nrog uas muaj ib tug kub gradient nyob rau hauv lawv, tshwj tsis yog Joule tshav kub tso tawm los yog haum ntawm ntxiv cov nqi ntawm cov cua sov yuav tshwm sim nyob rau hauv cov kev coj nyob rau hauv uas tam sim no yuav ntws.

Tsis txaus niaj hnub tshem me me cua sov, muaj ib tug homogeneous qauv muaj feem xyuam rau nws cov khoom, uas cov ntaub ntawv uas yuav tsis niaj hnub. Yog li, lub Thomson nyhuv yog ib lub phenomenon Peltier. Qhov txawv tsuas yog tias ntau yam uas tsis yog-tshuaj lom neeg muaj pes tsawg leeg ntawm tus qauv, thiab qhov kub thiab txias ntawm originality no heterogeneity.