Umgaqo okhanyayo we-LED

Konkeisibane somsebenzi oHlangeneyo kwakhona, isibane esiphathwayo senkampukwayeisibane sentloko esisebenzayosebenzisa uhlobo lwebhalbhu ye-LED. Ukuqonda umgaqo we-diode okhokelwayo, okokuqala ukuqonda ulwazi olusisiseko lwee-semiconductors. Iimpawu zokuqhuba izinto ze-semiconductor ziphakathi kwee-conductor kunye ne-insulators. Iimpawu zayo ezizodwa: xa i-semiconductor ikhuthazwa kukukhanya kwangaphandle kunye neemeko zokushisa, amandla ayo okuqhuba aya kutshintsha kakhulu; Ukongeza amanani amancinci okungcola kwi-semiconductor ecocekileyo kwandisa kakhulu amandla ayo okuqhuba umbane. I-silicon (Si) kunye ne-germanium (Ge) zezona zixhaphakileyo ze-semiconductors kwii-electronics zanamhlanje, kwaye ii-electron zazo zangaphandle zine. Xa i-silicon okanye i-athomu ze-germanium zenza ikristale, ii-athom ezingabamelwane zisebenzisana, ukuze ii-electron zangaphandle zibe zabelwana ngee-athom ezimbini, ezenza i-covalent bond structure kwi-crystal, isakhiwo se-molecular esinamandla amancinci. Kwiqondo lobushushu begumbi (300K), ukuvuswa kwe-thermal kuya kwenza ezinye ii-electron zangaphandle zifumane amandla awoneleyo okuqhawula kwi-covalent bond kwaye zibe zii-electron zasimahla, le nkqubo ibizwa ngokuba yi-intrinsic excitation. Emva kokuba i-electron ingabophelwanga ukuba ibe yi-electron yamahhala, isithuba sishiywe kwi-covalent bond. Esi sithuba sibizwa ngokuba ngumngxuma. Ukubonakala komngxuma yinto ebalulekileyo eyahlula i-semiconductor kumqhubi.

Xa isixa esincinci sokungcola kwe-pentavalent njenge-phosphorus yongezwa kwi-intrinsic semiconductor, iya kuba ne-electron eyongezelelweyo emva kokwenza i-covalent bond kunye nezinye ii-athom ze-semiconductor. Le electron eyongezelelweyo ifuna kuphela amandla amancinane kakhulu ukulahla ibhondi kwaye ibe yi-electron yasimahla. Olu hlobo lwe-semiconductor yokungcola lubizwa ngokuba yi-electronic semiconductor (N-type semiconductor). Nangona kunjalo, ukongeza inani elincinci le-trivalent elemental ukungcola (okufana ne-boron, njl.njl.) kwi-intrinsic semiconductor, kuba inee-electron ezintathu kuphela kumaleko angaphandle, emva kokwenza i-covalent bond kunye ne-athomu ye-semiconductor ejikelezileyo, iya kudala isithuba. kwikristale. Olu hlobo lwesemiconductor yokungcola lubizwa ngokuba semiconductor yomngxuma (P-type semiconductor). Xa i-N-type kunye ne-P-type semiconductors zidityanisiwe, kukho umehluko ekuxininiseni kwee-electron zamahhala kunye nemingxuma ekudibaneni kwabo. Zombini ii-elektroni kunye nemingxuma zisasazwe ukuya kugxininiso olusezantsi, zishiya ngasemva ii-ion ezihlawulweyo kodwa ezingashukumiyo ezitshabalalisa ubundilele bombane bokuqala bohlobo lwe-N kunye nohlobo lwemimandla ye-P. La masuntswana ahlawuliswayo angashukumiyo adla ngokubizwa ngokuba ziindleko zesithuba, kwaye agxininiswe kufutshane nojongano lwemimandla ye-N kunye ne-P ukwenza ummandla obhityileyo kakhulu wentlawulo yesithuba, owaziwa ngokuba yi-PN junction.

Xa i-voltage ye-bias yangaphambili isetyenziswe kuzo zombini iziphelo ze-PN junction (i-voltage echanekileyo ukuya kwelinye icala lohlobo lwe-P), imingxuma kunye nee-electron zamahhala zihamba ngeenxa zonke, zenza indawo yombane yangaphakathi. Imingxunya esanda kufakwa emva koko iphinda ihlangane kunye nee-electron zamahhala, ngamanye amaxesha ikhupha amandla angaphezulu ngendlela yeefotoni, ukukhanya esikubonayo kukhutshwa zii-leds. I-spectrum enjalo incinci, kwaye ekubeni yonke into ine-gap yebhendi eyahlukileyo, ubude be-wavelengths yeefotoni ezikhutshwayo ziyahluka, ngoko ke imibala yee-lead igqitywe ngezinto ezisisiseko ezisetyenzisiweyo.