Ko te kaupapa mārama o te LED

Katoate rama mahi ka taea te whakahou, rama puni kawemerama matua maha-mahiWhakamahia te momo pūangi LED. Hei mārama ki te kaupapa o te diode led, me mārama tuatahi ki te mōhiotanga taketake o ngā semiconductors. Ko ngā āhuatanga kawe o ngā rauemi semiconductors kei waenganui i ngā conductors me ngā insulators. Ko ōna āhuatanga ahurei ko: ina whakaohokia te semiconductors e ngā āhuatanga o te mārama me te wera o waho, ka tino rerekē tōna kaha kawe; Mā te tāpiri i ngā poke iti ki te semiconductors parakore ka nui ake tōna kaha ki te kawe hiko. Ko te Silicon (Si) me te germanium (Ge) ngā semiconductors e whakamahia whānuitia ana i roto i ngā hikohiko hou, ā, e whā ō rātou irahiko o waho. Ina hangaia he tioata e ngā ngota silicon, germanium rānei, ka taunekeneke ngā ngota tata ki a rātou anō, kia tohaina ai ngā irahiko o waho e ngā ngota e rua, ka hangaia te hanganga here covalent i roto i te tioata, he hanganga ngota me te iti o te kaha here. I te pāmahana rūma (300K), ka meinga e te whakaoho wera ētahi irahiko o waho kia nui te kaha ki te wehe atu i te here covalent ka noho hei irahiko kore utu, ka kiia tēnei tukanga he whakaoho ā-roto. I muri i te wetekina o te irahiko hei irahiko kore utu, ka waiho he takoto kau i roto i te here covalent. Ka kiia tēnei takoto kau he kōhao. Ko te āhua o te kōhao he āhuatanga nui e wehewehe ai i te haurua-whakawhiti mai i te ara iahiko.

Ina tāpirihia he iti noa te poke pentavalent pērā i te phosphorus ki te semiconductor ā-roto, ka nui ake te irahiko i muri i te hanga hononga covalent me ētahi atu ngota semiconductor. He iti noa te kaha e hiahiatia ana e tēnei irahiko tāpiri hei tango i te hononga, hei huri hei irahiko kore utu. Ka kiia tēnei momo semiconductor poke he semiconductor hiko (semiconductor momo-N). Heoi, mā te tāpiri i te iti noa o ngā poke huānga trivalent (pērā i te boron, me ētahi atu) ki te semiconductor ā-roto, nā te mea e toru noa iho ngā irahiko i te paparanga o waho, i muri i te hanga hononga covalent me ngā ngota semiconductor e karapoti ana, ka puta he wāhi kore i roto i te tioata. Ka kiia tēnei momo semiconductor poke he semiconductor poka (semiconductor momo-P). Ina whakakotahihia ngā semiconductor momo-N me te momo-P, ka rerekē te kukū o ngā irahiko kore utu me ngā poka i tō rāua hononga. Ka horapa ngā irahiko me ngā poka ki te kukū iti iho, ka waiho ngā iona kua utua engari kāore e nekeneke e whakangaro ana i te kore hiko taketake o ngā rohe momo-N me te momo-P. Ko ēnei matūriki utu kore nekeneke e kiia ana he utu ātea, ā, ka kukū tata ki te atanga o ngā rohe N me P hei hanga i tētahi rohe utu ātea tino angiangi, e mōhiotia ana ko te hononga PN.

Ina whakamahia he ngaohiko whakahāngai whakamua ki ngā pito e rua o te hononga PN (ngaohiko pai ki tetahi taha o te momo-P), ka neke ngā kōhao me ngā irahiko kore utu tetahi ki tetahi, ka hanga he papa hiko ā-roto. Kātahi ka honoa anō ngā kōhao hou kua werohia ki ngā irahiko kore utu, ka tukuna i ētahi wā te kaha nui i roto i te ahua o ngā photon, koinei te mārama e kitea ana e tātou e tukuna ana e ngā rama LED. He whaiti te whānuitanga o tēnei, ā, nā te mea he rerekē te āputa roopu o ia rauemi, he rerekē ngā roangaru o ngā photon e tukuna ana, nō reira ka whakatauhia ngā tae o ngā rama LED e ngā rauemi taketake e whakamahia ana.