Mfundo yowala ya LED

Zonsenyali yogwira ntchito yowonjezereka, nyali zonyamula msasandimultifunctional headlampgwiritsani ntchito babu la LED. Kuti timvetse mfundo ya diode anatsogolera, choyamba kumvetsa mfundo zikuluzikulu za semiconductors. Ma conductive a zida za semiconductor ali pakati pa ma conductor ndi ma insulators. Makhalidwe ake apadera ndi awa: pamene semiconductor imalimbikitsidwa ndi kuwala kwakunja ndi kutentha kwakunja, mphamvu yake yoyendetsa idzasintha kwambiri; Kuonjezera zonyansa zazing'ono ku semiconductor yoyera kumawonjezera mphamvu yake yoyendetsa magetsi. Silicon (Si) ndi germanium (Ge) ndi ma semiconductors omwe amagwiritsidwa ntchito kwambiri pamagetsi amakono, ndipo ma elekitironi awo akunja ndi anayi. Pamene silikoni kapena germanium maatomu kupanga krustalo, maatomu oyandikana kucheza wina ndi mzake, kuti ma elekitironi akunja kukhala nawo maatomu awiri, zomwe zimapanga covalent chomangira dongosolo mu krustalo, amene ndi maselo dongosolo ndi pang'ono chopinga luso. Pa kutentha kwa firiji (300K), kutentha kwa matenthedwe kumapangitsa ma elekitironi ena akunja kukhala ndi mphamvu zokwanira kuti achoke ku mgwirizano wa covalent ndikukhala ma elekitironi aulere, njirayi imatchedwa chisangalalo chamkati. Pambuyo pa electron sichimamangidwa kuti ikhale electron yaulere, malo amasiyidwa mu mgwirizano wa covalent. Ntchito imeneyi imatchedwa dzenje. Maonekedwe a dzenje ndi chinthu chofunikira chomwe chimasiyanitsa semiconductor ndi conductor.

Pamene zonyansa zochepa za pentavalent monga phosphorous zikuwonjezeredwa ku intrinsic semiconductor, zimakhala ndi electron yowonjezera pambuyo popanga mgwirizano wogwirizana ndi maatomu ena a semiconductor. Ma elekitironi owonjezerawa amangofunika mphamvu zochepa kwambiri kuti achotse chomangiracho ndikukhala electron yaulere. Mtundu uwu wa semiconductor wonyansa umatchedwa electronic semiconductor (N-type semiconductor). Komabe, kuwonjezera pang'ono trivalent elemental zonyansa (monga boron, etc.) kwa intrinsic semiconductor, chifukwa ali ma elekitironi atatu okha mu wosanjikiza akunja, pambuyo kupanga covalent chomangira ndi ozungulira semiconductor maatomu, izo kulenga ntchito. mu kristalo. Mtundu uwu wa semiconductor wonyansa umatchedwa hole semiconductor (P-type semiconductor). Pamene ma semiconductors amtundu wa N ndi P aphatikizidwa, pali kusiyana pakati pa ma elekitironi aulere ndi mabowo pamphambano zawo. Ma electron onse ndi mabowo amagawidwa kumunsi kwa ndende, ndikusiya ma ion opangidwa koma osasunthika omwe amawononga kusalowerera ndale kwamagetsi koyambirira kwa zigawo za N-mtundu ndi P. Tinthu tating'ono ting'onoting'ono timeneti timene timatulutsa timadzi timene timatchedwa kuti danga, ndipo timayika pafupi ndi mawonekedwe a madera a N ndi P kuti apange chigawo chochepa kwambiri cha danga, chomwe chimadziwika kuti PN mp3.

Pamene voteji ya kutsogolo ikugwiritsidwa ntchito kumapeto onse a PN mphambano (voltage yabwino kumbali imodzi ya mtundu wa P), mabowo ndi ma elekitironi aulere amayendayenda, ndikupanga munda wamagetsi wamkati. Mabowo omwe angobadwira kumenewo amalumikizananso ndi ma elekitironi aulere, nthawi zina kutulutsa mphamvu zochulukirapo monga ma photons, kuwala komwe timawona kutulutsidwa ndi ma LED. Sipekitiramu yotereyi ndi yopapatiza, ndipo popeza chilichonse chili ndi kusiyana kosiyana kwa gulu, mafunde a ma photons opangidwa ndi osiyana, kotero mitundu ya ma LED imatsimikiziridwa ndi zida zoyambira zomwe zimagwiritsidwa ntchito.