Gakondo LED yahinduye urwego rwo kumurika no kwerekana bitewe nibikorwa byabo byiza murwego rwo gukora neza, gutuza nubunini bwibikoresho. LED mubisanzwe ni uduce twa firime ya semiconductor yoroheje ifite uburebure bwa milimetero, ntoya cyane ugereranije nibikoresho gakondo nka bulbes ya incandescent na tebo ya cathode. Nyamara, kugaragara kwa optoelectronic progaramu, nkibintu byukuri kandi byongerewe ukuri, bisaba LED mubunini bwa micron cyangwa munsi yayo. Icyizere nuko micro - cyangwa submicron igipimo LED (µleds) ikomeje kugira imico myinshi isumba iyindi myenda isanzwe ifite, nko kohereza imyuka ihumanya cyane, gukora neza no kumurika, gukoresha ingufu zidasanzwe, no gusohora amabara yuzuye, mugihe kuba inshuro zigera kuri miriyoni mukarere, kwemerera kwerekana byinshi. Imashini nk'izo ziyobowe nazo zishobora gutanga inzira yumuzunguruko ukomeye wa fotonike niba ishobora guhingwa imwe imwe kuri Si kandi igahuzwa nicyuma cyuzuzanya cyuma cya semiconductor (CMOS).
Nyamara, kugeza ubu, µleds zagumye zoroshye, cyane cyane mu cyatsi kibisi gitukura. Uburyo gakondo buyobowe µ buyobowe nuburyo bwo hejuru-hasi aho InGaN quantum well (QW) yinjizwa mubikoresho biciriritse binyuze muburyo bwo gutobora. Mugihe firime yoroheje InGaN QW ishingiye kuri tio2 µleds yakunze kwitabwaho cyane kubera byinshi mubintu byiza bya InGaN, nko gutwara ibintu neza no gutwara imirongo yumurambararo murwego rugaragara, kugeza ubu bagiye bahura nibibazo nkurukuta-mpande kwangirika kwangirika gukomera uko ingano yibikoresho igabanuka. Mubyongeyeho, bitewe no kubaho kwa polarisiyasi, bafite uburebure bwumurongo / ibara ridahungabana. Kuri iki kibazo, hashyizweho ibisubizo bitari polar na kimwe cya kabiri InGaN hamwe na fotonike ya kristal cavity ibisubizo, ariko ntibishimishije muri iki gihe.
Mu mpapuro nshya zasohotse muri Light Science and Applications, abashakashatsi bayobowe na Zetian Mi, umwarimu muri kaminuza ya Michigan, Annabel, bakoze ubushakashatsi bwerekana icyatsi kibisi LED iii - nitride itsinze izo nzitizi burundu. Izi µleds zashizwe hamwe na plasma yo mukarere yatoranijwe ifashwa na molekulari beam epitaxy. Bitandukanye cyane nuburyo gakondo bwo hejuru-hasi, µled hano igizwe numurongo wa nanowire, buri kimwe cya 100 kugeza 200 nm cya diametre, gitandukanijwe na nanometero icumi. Ubu buryo bwo hejuru-bwirinda cyane cyane kwangirika kwurukuta.
Igice cyohereza urumuri rw'igikoresho, kizwi kandi nk'akarere gakora, kigizwe na core-shell inshuro nyinshi kwantumatima (MQW) imiterere irangwa na nanowire morphologie. By'umwihariko, MQW igizwe na InGaN neza na bariyeri ya AlGaN. Bitewe no gutandukana kwimuka rya atom ryimuka ryitsinda rya III indium, gallium na aluminium kurukuta rwuruhande, twasanze indium yabuze kurukuta rwuruhande rwa nanowires, aho igikonoshwa cya GaN / AlGaN cyapfunyitse intoki ya MQW nka burrito. Abashakashatsi basanze ibirimo Al biri muri iki gishishwa cya GaN / AlGaN byagabanutse buhoro buhoro kuva kuruhande rwa elegitoronike ya nanowire kugera kuruhande. Bitewe no gutandukanya imbere muri polarisiyasi yimbere ya GaN na AlN, ingano ya gradient yibintu bya Al murwego rwa AlGaN itera electroni yubusa, byoroshye gutembera mumikorere ya MQW no kugabanya ihungabana ryamabara mugabanya umurima wa polarisiyasi.
Mubyukuri, abashakashatsi basanze kubikoresho bitarenze micron imwe ya diametre, uburebure bwumurambararo wa electroluminescence, cyangwa urumuri ruturuka kumuriro, bikomeza guhora kumurongo wubunini bwimpinduka ziterwa inshinge. Byongeye kandi, itsinda rya Porofeseri Mi ryashyizeho uburyo bwo gukura ibifuniko byiza bya GaN kuri silicon kugirango bikure nanowire kuri silicon. Rero, µled yicaye kuri Si substrate yiteguye kwishyira hamwe nibindi bikoresho bya elegitoroniki ya CMOS.
Iyi µled byoroshye ifite porogaramu nyinshi zishoboka. Ihuriro ryibikoresho bizarushaho gukomera uko uburebure bw’imyuka yoherezwa ya RGB yerekanwe kuri chip yaguka itukura.
Igihe cyo kohereza: Mutarama-10-2023