Semiconductor vs Hlau
Metals
Hlau yog paub rau tib neeg lub sijhawm ntev heev. Muaj cov pov thawj los ua pov thawj txog kev siv hlau rov qab rau xyoo 6000 BC. Kub thiab tooj liab yog thawj cov hlau uas tau pom. Cov no tau siv los ua cov cuab yeej, cov hniav nyiaj hniav kub, cov mlom, thiab lwm yam. Txij thaum ntawd los, tsuas yog ob peb lwm yam hlau (17) tau pom. Tam sim no peb paub txog 86 hom hlau sib txawv. Cov hlau tseem ceeb heev vim lawv cov yam ntxwv tshwj xeeb. Feem ntau cov hlau yog tawv thiab muaj zog (tseem muaj kev zam rau qhov no xws li sodium. Sodium tuaj yeem txiav los ntawm riam). Mercury yog cov hlau, uas yog nyob rau hauv cov kua hauv lub xeev. Dhau li ntawm mercury, tag nrho lwm cov hlau muaj nyob rau hauv cov khoom muaj zog, thiab nws yog ib qho nyuaj rau tawg los yog hloov lawv cov duab piv rau lwm yam uas tsis yog-hlau ntsiab. Cov hlau muaj qhov ci ntsa iab. Feem ntau ntawm lawv muaj ib tug silvery ci (tshwj tsis yog kub thiab tooj liab). Txij li thaum qee cov hlau muaj zog heev nrog cov pa cua zoo li cov pa oxygen, lawv yuav tau txais cov xim du thaum lub sijhawm. Qhov no feem ntau yog los ntawm kev tsim cov hlau oxide txheej. Ntawm qhov tod tes, cov hlau zoo li kub thiab platinum yog qhov ruaj khov thiab tsis muaj zog. Cov hlau yog Malleable thiab ductile, uas tso cai rau lawv siv los ua qee yam cuab yeej. Cov hlau yog atoms, uas tuaj yeem tsim cations los ntawm kev tshem tawm cov electrons. Yog li lawv yog electro-positive. Hom kev sib txuas ntawm cov hlau atoms hu ua metallic bonding. Cov hlau tso tawm electrons nyob rau hauv lawv cov plhaub sab nrauv thiab cov electrons tau tawg ntawm cov hlau cations. Yog li ntawd, lawv lub npe hu ua lub hiav txwv ntawm delocalized electrons. Cov electrostatic kev sib cuam tshuam ntawm cov electrons thiab cations yog hu ua metallic bonding. Cov electrons tuaj yeem txav tau; yog li ntawd, hlau muaj peev xwm ua tau hluav taws xob. Tsis tas li ntawd, lawv yog cov thermal conductors zoo. Vim yog cov hlau nplaum sib txuas hlau muaj cov qauv txiav txim. Cov ntsiab lus melting siab thiab cov ntsiab lus kub ntawm cov hlau kuj yog vim cov hlau nplaum muaj zog. Ntxiv mus, cov hlau muaj qhov ntom ntom dua li dej. Cov ntsiab lus hauv pawg IA, IIA yog cov hlau teeb. Lawv muaj qee qhov txawv ntawm cov lus piav qhia saum toj no ntawm cov hlau.
Semiconductor
Cov khoom siv yog cov khoom siv hluav taws xob siab. Insulators yog cov khoom siv uas tsis muaj hluav taws xob. Semiconductors yog cov ntaub ntawv nyob rau hauv nruab nrab ntawm conductors thiab insulators. Yog li nws cov hluav taws xob conductivity nyob nruab nrab ntawm cov conductors thiab insulators. Ib qho semiconductor tuaj yeem yog ib qho khoom lossis cov khoom sib xyaw. Silicon yog cov khoom siv feem ntau siv los ua cov khoom siv semiconductor. Germanium kuj yog ib qho piv txwv rau qhov no. Lub conductivity ntawm no ntshiab keeb yog hloov los ntawm kev ntxiv ntau yam ntawm impurities. Cov no yog hu ua dopants thiab ntxiv ntawm cov no yog hu ua doping. Feem ntau siv dopants rau silicon yog boron lossis phosphorus. Doped semiconductors tseem hu ua extrinsic. Lwm yam tshaj li cov ntsiab lus, cov organic tebchaw kuj tuaj yeem ua cov khoom siv semiconductors. Lub mechanism ntawm hluav taws xob ua nyob rau hauv semiconductors yog txawv. Qee cov semiconductors nqa hluav taws xob los ntawm electrons (N hom) thaum qee qhov nqa hluav taws xob los ntawm qhov zoo them (p hom). Semiconductors tau siv dav hauv cov khoom siv hluav taws xob xws li khoos phis tawj, xov tooj cua, xov tooj, thiab lwm yam. lawv kuj muaj nyob rau hauv lub hnub ci hlwb, transistors, diodes, thiab lwm yam.
Qhov txawv ntawm Semiconductor thiab Hlau yog dab tsi?
• Cov hlau yog cov khoom siv hluav taws xob thiab yog li lawv nqa hluav taws xob ntau. Semiconductors muaj hluav taws xob conductivity tsawg dua hlau.
• Hauv cov hlau electrons nqa tawm tam sim no. Tab sis nyob rau hauv semiconductors, tam sim no yog nqa tawm los ntawm ntws ntawm electrons ntawm zoo them qhov.
