Isifinyezo: Isakhiwo esiyisisekelo kanye nesimiso sokusebenza se-avalanche photodetector (Isitholi sezithombe se-APD) ziyaqaliswa, inqubo yokuziphendukela kwemvelo yesakhiwo sedivayisi iyahlaziywa, isimo socwaningo lwamanje siyafingqwa, futhi intuthuko yesikhathi esizayo ye-APD ifundwa ngendlela eqhubekayo.
1. Isingeniso
I-photodetector iyithuluzi eliguqula izimpawu zokukhanya zibe izimpawu zikagesi.isitholi sesithombe se-semiconductor, isithwali esikhiqizwe ngesithombe esivuswe yi-photon yesigameko singena kwisekethe yangaphandle ngaphansi kwe-voltage ye-bias esetshenzisiwe futhi sakha i-photocurrent elinganisekayo. Ngisho noma isabela kakhulu, i-PIN photodiode ingakhiqiza kuphela amabhangqa amabili e-electron-hole okungenani, okuyidivayisi engenanzuzo yangaphakathi. Ukuze kuphenduleke kakhulu, i-avalanche photodiode (APD) ingasetshenziswa. Umphumela wokukhulisa we-APD ku-photocurrent usekelwe kumphumela wokushayisana kwe-ionization. Ngaphansi kwezimo ezithile, ama-electron asheshisiwe kanye nezimbobo zingathola amandla anele okushayisana ne-lattice ukukhiqiza amabhangqa amasha e-electron-hole. Le nqubo iyindlela yokusabela kweketanga, ukuze amabhangqa amabili e-electron-hole akhiqizwe ukumuncwa kokukhanya angakhiqiza inani elikhulu lamabhangqa amabili e-electron-hole futhi akhe i-photocurrent yesibili enkulu. Ngakho-ke, i-APD inokusabela okuphezulu kanye nenzuzo yangaphakathi, okuthuthukisa isilinganiso sesignali-kuya-kumsindo sedivayisi. I-APD izosetshenziswa kakhulu ezinhlelweni zokuxhumana ze-fiber ye-optical ezikude noma ezincane ezineminye imikhawulo emandleni optical atholiwe. Njengamanje, ochwepheshe abaningi bamadivayisi optical banethemba elikhulu ngamathuba e-APD, futhi bakholelwa ukuthi ucwaningo lwe-APD luyadingeka ukuze kuthuthukiswe ukuncintisana kwamazwe ngamazwe emikhakheni ehlobene.
2. Intuthuko yobuchwepheshe yeumshini wokuthola izithombe we-avalanche(Isitholi sezithombe se-APD)
2.1 Izinto Zokusebenza
(1)Isitholi sezithombe
Ubuchwepheshe bezinto ezibonakalayo be-Si buwubuchwepheshe obuvuthiwe obusetshenziswa kabanzi emkhakheni we-microelectronics, kodwa abufaneleki ukulungiswa kwamadivayisi asezingeni lobude be-wavelength elingu-1.31mm no-1.55mm amukelwa kabanzi emkhakheni wokuxhumana kwe-optical.
(2)Ge
Nakuba impendulo ye-spectral ye-Ge APD ifanelekela izidingo zokulahlekelwa okuphansi kanye nokusabalala okuphansi ekudlulisweni kwe-optical fiber, kunezinkinga ezinkulu enkambisweni yokulungiselela. Ngaphezu kwalokho, isilinganiso se-electron kanye ne-hole ionization rate sikaGe siseduze no-() 1, ngakho-ke kunzima ukulungiselela amadivayisi e-APD asebenza kahle kakhulu.
(3)Ku-0.53Ga0.47As/InP
Kuyindlela ephumelelayo yokukhetha i-In0.53Ga0.47Njengoba ungqimba lokumunca ukukhanya lwe-APD ne-InP luyingqimba yokuphindaphinda. Isilinganiso sokumunca sezinto ze-In0.53Ga0.47As singu-1.65mm, ubude be-1.31mm, 1.55mm cishe singu-104cm-1 high absorption coefficient, okuyizinto ezikhethwayo zengqimba yokumunca yesitholi sokukhanya okwamanje.
(4)Isitholi sezithombe se-InGaAs/Ngaphakathiumshini wokuthola izithombe
Ngokukhetha i-InGaAsP njengesendlalelo esimunca ukukhanya kanye ne-InP njengesendlalelo esiphindaphindayo, i-APD enobude besikhathi bokuphendula obungu-1-1.4mm, ukusebenza kahle kwe-quantum ephezulu, ugesi omnyama ophansi kanye nokwanda kwe-avalanche ephezulu kungalungiswa. Ngokukhetha izingxenye ezahlukene ze-alloy, ukusebenza okuhle kakhulu kwama-wavelength athile kufinyelelwa.
(5)Ama-InGaA/Ama-InAlA
Izinto ze-In0.52Al0.48As zinegebe lebhendi (1.47eV) futhi azimunci ebangeni lamaza angu-1.55mm. Kunobufakazi bokuthi ungqimba oluncane lwe-In0.52Al0.48As epitaxial lungathola izici zokuzuza ezingcono kune-InP njengengqimba ye-multiplicator ngaphansi kwesimo sokufakwa kwe-electron emsulwa.
(6)InGaAs/InGaAs (P) /InAlAs kanye nama-InGaAs/In (Al) GaAs/InAlAs
Izinga lokushintshashintsha kwe-ionization yezinto liyisici esibalulekile esithinta ukusebenza kwe-APD. Imiphumela ikhombisa ukuthi izinga lokushintshashintsha kwe-ionization kwesendlalelo sokuphindaphinda lingathuthukiswa ngokwethula izakhiwo ze-InGaAs (P) /InAlAs kanye ne-In (Al) GaAs/InAlAs superlattice. Ngokusebenzisa isakhiwo se-superlattice, ubunjiniyela be-band bungalawula ngokwenziwa ukungaguquki komphetho webhendi okungalingani phakathi kwebhendi yokuqhuba kanye namanani ebhendi ye-valence, futhi kuqinisekiswe ukuthi ukungaguquki kwebhendi yokuqhuba kukhulu kakhulu kunokungaguquki kwebhendi ye-valence (ΔEc>>ΔEv). Uma kuqhathaniswa nezinto eziningi ze-InGaAs, izinga lokushintshashintsha kwe-electron electron well (a) le-InGaAs/InAlAs quantum well (a) likhuphuka kakhulu, futhi ama-electron kanye nezimbobo zithola amandla engeziwe. Ngenxa ye-ΔEc>>ΔEv, kungalindelwa ukuthi amandla atholwe ama-electron akhulisa izinga lokushintshashintsha kwe-electron kakhulu kunomnikelo wamandla embobo kwizinga lokushintshashintsha kwe-ionization yembobo (b). Isilinganiso (k) sezinga lokushintshashintsha kwe-electron kwizinga lokushintshashintsha kwe-ionization yembobo siyanda. Ngakho-ke, umkhiqizo we-gain-bandwidth ephezulu (GBW) kanye nokusebenza komsindo ophansi kungatholakala ngokusebenzisa izakhiwo ze-superlattice. Kodwa-ke, lesi sakhiwo se-InGaAs/InAlAs quantum well APD, esingakhuphula inani le-k, kunzima ukusisebenzisa kuma-optical receivers. Lokhu kungenxa yokuthi isici sokuphindaphinda esithinta ukuphendula okuphezulu sinqunyelwe ugesi omnyama, hhayi umsindo wokuphindaphinda. Kulesi sakhiwo, ugesi omnyama ubangelwa kakhulu umphumela we-tunneling wengqimba yomthombo we-InGaAs ene-band gap encane, ngakho-ke ukwethulwa kwe-quaternary alloy ye-wide-band gap, njenge-InGaAsP noma i-InAlGaAs, esikhundleni se-InGaAs njengengqimba yomthombo wesakhiwo somthombo we-quantum kungacindezela ugesi omnyama.
Isikhathi sokuthunyelwe: Novemba-13-2023