Tsis ntev los no, pab pawg tshawb fawb ntawm Sun Haiding thiab Long Shibing ntawm Lub Tsev Kawm Ntawv ntawm Microelectronics ntawm University of Science thiab Technology ntawm Tuam Tshoj tau ua tiav hauv qhov kev vam meej tseem ceeb ntawm UV LED luminescence kev ua tau zoo nrog rau kev siv sapphire substrate chamfer angle tswj quantum zoo kom ua tiav peb-dimensional cab kuj kaw.
Txawm hais tias ultraviolet rays suav rau tsuas yog 5% ntawm lub zog hauv tshav ntuj, lawv tau siv dav hauv tib neeg lub neej. Tam sim no, lub teeb ci ultraviolet tau siv dav hauv dej huv, kho lub teeb, ua kom tsis muaj menyuam thiab tua kab mob. Cov khoom siv hluav taws xob ultraviolet feem ntau siv lub xeev zoo siab ntawm mercury vapor paug los tsim hluav taws xob ultraviolet, uas muaj ntau qhov tsis xws xws li tsim hluav taws xob loj, siv hluav taws xob siab, teb qeeb, lub neej luv, thiab muaj kev phom sij txaus ntshai. Qhov sib sib zog nqus-ultraviolet lub teeb tshiab siv lub teeb ci-emitting diode (LED) txoj cai, uas muaj ntau yam zoo dua li cov tsoos mercury teeb. Ntawm lawv, qhov txiaj ntsig tseem ceeb tshaj plaws yog tias nws tsis muaj cov tshuaj mercury lom. Kev siv ntawm" Minamata Convention" kwv yees hais tias kev siv cov teeb ci uas muaj mercury-muaj ultraviolet yuav raug txwv tsis pub siv rau xyoo 2020. Yog li ntawd, kev tsim cov khoom lag luam-tshiab-ib puag ncig-phooj ywg, ua kom muaj txiaj ntsig ultraviolet lub teeb tau dhau los ua qhov nyuaj rau cov tib neeg.
Raws li qhov tshwm sim, nqus ultraviolet lub teeb-emitting diodes (UV LEDs) raws qhov dav-bandgap semiconductor cov ntaub ntawv (gallium nitride, aluminium gallium nitride) tau dhau los ua qhov kev xaiv zoo tshaj plaws rau daim ntawv thov tshiab no. Txhua qhov khoom siv hauv lub xeev lub teeb pom kev zoo yog qhov ua tau zoo, me me, thiab muaj lub neej ntev. Nws tsuas yog ib qho nti me me ntawm tus ntiv tes xoo npog thiab tuaj yeem tso lub teeb ci ultraviolet muaj zog dua li lub teeb mercury. Qhov tsis meej nyob ntawm no feem ntau yog nyob ntawm cov khoom sib txuas ncaj qha cov khoom siv hluav taws xob ntawm III-nitride: thaum cov hluav taws xob hauv cov kab sib txuas ua ke sib txuas nrog qhov nyob hauv cov pab pawg valence, cov duab tau tsim. Lub zog ntawm photon nyob ntawm qhov sib txawv ntawm cov khoom, yog li cov kws tshawb fawb tuaj yeem hloov kho qhov sib xyaw ua ke hauv ternary sib xyaw ntawm aluminium gallium nitride (AlGaN) kom ua tiav qhov sib txawv nthwv dej ntawm lub teeb tso tawm. Txawm li cas los xij, nws tsis yog qhov yooj yim kom ua tiav lub teeb pom kev zoo ntawm UV LEDs. Cov kws tshawb fawb tau tshawb pom tias thaum cov hluav taws xob thiab lub qhov sib sau ua ke, photons tsis tau tsim ib txwm. Qhov kev ua tau zoo no hu ua Internal quantum efficiency (IQE).
Sib txawv los ntawm cov qauv UV LED ib txwm muaj, tuab tuab ntawm qhov muaj peev xwm zoo thiab muaj peev xwm tiv thaiv txheej txheej ntawm cov teeb pom kev zoo ntawm cov txheej txheem tshiab no, ntau txheej quantum zoo (MQW), tsis zoo li qub. Nrog kev pab los ntawm kev daws teeb meem siab lub tshuab hluav taws xob me me, cov kws tshawb fawb muaj peev xwm txheeb xyuas cov txheej txheem zoo ntawm tsuas yog ob peb nanometers ntawm qhov ntsuas me me. Cov kev tshawb fawb tau pom tias gallium (Ga) atoms yuav sib sau ua ke ntawm cov theem hauv qab, uas ua rau nqaim ntawm cov pab pawg siv hluav taws xob hauv cheeb tsam, thiab raws li zaj duab xis loj hlob, Ga-nplua nuj thiab AI-nplua nuj cheeb tsam yuav txuas ntxiv mus rau DUV LED Qhov saum npoo yog tsis sib haum thiab khoov hauv qhov chaw peb-seem kom tsim tau peb-seem ntau yam quantum zoo qauv. Cov kws tshawb fawb hu qhov xwm txheej tshwj xeeb no: theem sib cais ntawm AI thiab Ga cov ntsiab lus thiab kev hloov chaw ntawm cov neeg nqa khoom. Nws yog qhov tsim nyog taw qhia tias nyob hauv indium gallium nitride (lnGaN) -based xiav LED system, ln thiab Ga tsis yog 100% tsis raug, ua rau ln-nplua nuj thiab Ga-nplua nuj thaj tsam hauv cov khoom, ua rau lub xeev hauv cheeb tsam thiab txhawb nqa chaw thau khoom Radiation recombination ntawm currents. Tab sis hauv AlGaN cov khoom siv, theem sib cais ntawm Al thiab Ga tsis tshua pom. Ib lub ntsiab lus tseem ceeb ntawm txoj haujlwm no yog txhawm rau txhawm rau kho qhov kev loj hlob ntawm cov khoom, txhawb qib sib cais, thiab yog li zoo heev txhim kho lub teeb pom kev zoo ntawm cov cuab yeej.
Qhov kev tshawb fawb no yuav muab cov tswv yim tshiab rau kev tshawb fawb thiab kev txhim kho kom muaj txiaj ntsig zoo ntawm txhua lub zog-lub xeev UV teeb pom kev zoo. Lub tswv yim no tsis xav tau cov qauv txheej txheem kim thiab cov txheej txheem kev loj hlob epitaxial. Kev cia siab tsuas yog hloov kho ntawm lub kaum sab xis bevel ntawm substrate thiab sib txuam thiab ua kom zoo dua ntawm epitaxial kev loj hlob tsis, nws cia siab tias cov yam ntxwv luminous ntawm UV LEDs tuaj yeem txhim kho rau qhov siab piv rau ntawm xiav LEDs, tso kev sim rau daim ntawv thov loj ntawm lub zog loj sib sib zog nqus UV LEDs. Thiab theoretical hauv paus.
