I-LED yendabuko itshintshe kakhulu icandelo lokukhanyisa nokubonisa ngenxa yokusebenza kwayo okuphezulu ngokubhekiselele ekusebenzeni kakuhle, ukuzinza kunye nobukhulu besixhobo. Ii-LED zihlala ziyinqwaba yeefilimu ezincinci ze-semiconductor ezinemilinganiselo esecaleni yeemilimitha, ezincinci kakhulu kunezixhobo zemveli ezifana neebhalbhu ze-incandescent kunye neetyhubhu ze-cathode. Nangona kunjalo, usetyenziso oluvelayo lwe-optoelectronic, olufana ne-virtual kunye ne-augmented reality, zifuna ii-LED ezinobukhulu bee-microns okanye ngaphantsi. Ithemba kukuba ii-LED (µleds) ezincinci okanye ezingaphantsi kwe-micromicron ziyaqhubeka zineempawu ezininzi eziphezulu esele zinazo ii-LED zemveli, ezifana nokukhupha okuzinzileyo, ukusebenza kakuhle kunye nokukhanya okuphezulu, ukusetyenziswa kwamandla aphantsi kakhulu, kunye nokukhupha okugcweleyo, ngelixa zincinci ngokuphindwe kasigidi kwindawo, okuvumela ukubonisa okuncinci ngakumbi. Ezi chips ze-LED zinokuvula indlela yeesekethe ze-photonic ezinamandla ngakumbi ukuba zinokukhuliswa i-single-chip kwi-Si kwaye zidityaniswe ne-electronics ze-complementary metal oxide semiconductor (CMOS).
Nangona kunjalo, ukuza kuthi ga ngoku, ezi µleds azikafumaneki lula, ingakumbi kuluhlu lwe-wavelength eluhlaza ukuya kubomvu. Indlela yendabuko ye-led µ-led yinkqubo ephezulu apho iifilimu ze-InGaN quantum well (QW) zifakwa kwizixhobo ezincinci ngenkqubo yokukrola. Ngelixa ii-thin-film InGaN QW-based tio2 µleds zitsale ingqalelo enkulu ngenxa yeempawu ezininzi ezintle ze-InGaN, ezinje ngokuthuthwa kokuthwala okusebenzayo kunye nokulungiswa kwe-wavelength kulo lonke uluhlu olubonakalayo, kude kube ngoku ziye zahlushwa yimicimbi efana nomonakalo wokugqwala kodonga olusecaleni oqhubeka uba mandundu njengoko ubungakanani besixhobo buncipha. Ukongeza, ngenxa yokubakho kwamasimi e-polarisation, anokungazinzi kwe-wavelength/color. Kule ngxaki, izisombululo ze-InGaN kunye ne-photonic crystal cavity ezingezizo ze-polar kunye ne-semi-polar ziye zacetyiswa, kodwa azanelisi okwangoku.
Kwiphepha elitsha elipapashwe kwiLight Science and Applications, abaphandi abakhokelwa nguZetian Mi, uprofesa kwiYunivesithi yaseMichigan, uAnnabel, baphuhlise i-submicron green LED iii – nitride eyoyisa le miqobo kube kanye. Ezi µleds zenziwe yi-selective regional plasma-assisted molecular beam epitaxy. Ngokwahlukileyo kwindlela yendabuko yokuphuma phezulu ukuya ezantsi, i-µled apha inee-nanowires ezininzi, nganye inobubanzi obuyi-100 ukuya kwi-200 nm, ezahlulwe ngamashumi ee-nanometers. Le ndlela yokuphuma ezantsi ukuya phezulu ngokuyintloko ithintela umonakalo wokubola kodonga olusecaleni.
Inxalenye ekhupha ukukhanya kwesi sixhobo, eyaziwa ngokuba yi-active region, yenziwe ngezakhiwo ze-core-shell multiple quantum well (MQW) ezibonakaliswa yi-nanowire morphology. Ngokukodwa, i-MQW iqulathe i-InGaN well kunye ne-AlGaN barrier. Ngenxa yokwahluka kokufuduka kwe-atom efakwe kwi-Group III elements indium, gallium kunye ne-aluminium kwiindonga ezisecaleni, sifumanise ukuba i-indium yayingekho kwiindonga ezisecaleni ze-nanowires, apho i-GaN/AlGaN shell yayisonga i-MQW core njenge-burrito. Abaphandi bafumanise ukuba umxholo we-Al wale shell ye-GaN/AlGaN wehla kancinci ukusuka kwicala le-electron injection ye-nanowires ukuya kwicala le-hole injection. Ngenxa yokwahluka kwiindawo zangaphakathi ze-polarization ze-GaN kunye ne-AlN, i-volume gradient yomxholo we-Al kumaleko we-Al ibangela ii-electron zasimahla, ezilula ukungena kwi-MQW core kwaye zinciphise ukungazinzi kombala ngokunciphisa i-polarization field.
Enyanisweni, abaphandi bafumanise ukuba kwizixhobo ezingaphantsi kwe-micron enye ububanzi, ubude bomphezulu we-electroluminescence, okanye ukukhutshwa kokukhanya okubangelwa ngumbane, kuhlala kungaguquki ngokomlinganiselo wotshintsho kwi-current injection. Ukongeza, iqela likaNjingalwazi Mi ngaphambili liphuhlise indlela yokukhulisa ii-GaN coatings ezikumgangatho ophezulu kwi-silicon ukuze kukhuliswe ii-nanowire leds kwi-silicon. Ngoko ke, i-µled ihlala kwi-substrate ye-Si ilungele ukudityaniswa nezinye izixhobo ze-elektroniki ze-CMOS.
Le µled inezicelo ezininzi ezinokubakho. Iqonga lesixhobo liya komelela ngakumbi njengoko ubude bomda wokubonisa i-RGB edibeneyo kwi-chip bukhula bube bomvu.
Ixesha lokuposa: Jan-10-2023