Umgaqo kunye nemeko yangoku yei-avalanche photodetector (Isixhobo sokufota seAPD) Icandelo lesiBini
2.2 Isakhiwo se-chip ye-APD
Isakhiwo se-chip esifanelekileyo sisiqinisekiso esisisiseko sezixhobo zokusebenza eziphezulu.Uyilo lwesakhiwo se-APD ikakhulu luqwalasela ixesha le-RC elingaguqukiyo, ukubanjwa kwemingxuma kwi-heterojunction, ixesha lokuhamba kwe-carrier ngommandla wokunciphisa njalo njalo.Uphuhliso lwesakhiwo sayo lushwankathelwa ngezantsi:
(1) Isakhiwo esisisiseko
Isakhiwo esilula se-APD sisekelwe kwi-PIN photodiode, ummandla we-P kunye nommandla we-N ugxininiswe kakhulu, kwaye i-N-type okanye i-P-uhlobo lwe-double-repellant ingingqi yaziswa kwindawo ekufutshane ye-P okanye i-N ummandla wokuvelisa ii-electron zesibini kunye nomngxuma. izibini, ukuze uqonde ulwandiso lwefotocurrent yokuqala.Kwizinto zochungechunge lwe-InP, ngenxa yokuba i-coefficient ye-ionization yempembelelo yomngxuma inkulu kune-coefficient ye-ionization yempembelelo ye-electron, ummandla wokufumana i-N-uhlobo lwe-doping idla ngokubekwa kwingingqi ye-P.Kwimeko efanelekileyo, imingxuma kuphela ijojowe kwindawo yokuzuza, ngoko esi sakhiwo sibizwa ngokuba yi-hole-injected structure.
(2) Ukufunxa kunye nokuzuza kuyahlula
Ngenxa yeempawu ze-gap ezibanzi ze-InP (i-InP yi-1.35eV kunye ne-InGaAs yi-0.75eV), i-InP idla ngokusetyenziswa njengesixhobo sokufumana indawo kunye ne-InGaAs njengemathiriyeli yendawo yokufunxa.
(3) Ulwakhiwo lokufunxa, ukuthambeka kunye nokuzuza (SAGM) luyacetywa ngokulandelelanayo
Okwangoku, izixhobo ezininzi ze-APD zorhwebo zisebenzisa izinto ze-InP / InGaAs, i-InGaAs njengoluhlu lwe-absorption, i-InP phantsi kwendawo yombane ephezulu (> 5x105V / cm) ngaphandle kokuphuka, ingasetyenziselwa njengento yokuzuza indawo.Kulo mbandela, uyilo lwale APD kukuba inkqubo ye-avalanche yenziwe kwi-N-uhlobo lwe-InP ngokungqubana kwemingxuma.Ukuqwalasela umahluko omkhulu kwi-gap yebhendi phakathi kwe-InP kunye ne-InGaAs, umehluko wenqanaba lamandla malunga ne-0.4eV kwi-valence band yenza imingxuma eyenziwe kwi-InGaAs yokuxutywa kwe-absorption layer ivalwe kwi-heterojunction edge ngaphambi kokufikelela kwi-multiplier layer ye-InP kunye nesantya kakhulu. kuncitshiswe, okukhokelela kwixesha elide lokuphendula kunye ne-bandwidth emxinwa yale APD.Le ngxaki ingasombululwa ngokongeza i-InGaAsP yenguqu yomaleko phakathi kwezinto ezimbini.
(4) Ukufunxa, ukuthambeka, ukuhlawuliswa kunye nokuzuza (i-SAGCM) izakhiwo ziyacetywa ngokulandelelanayo.
Ukuze ulungelelanise ngakumbi ukuhanjiswa kwentsimi yombane yomaleko wokufunxa kunye nomgangatho wokuzuza, umaleko wentlawulo ungeniswa kuyilo lwesixhobo, esiphucula kakhulu isantya sesixhobo kunye nokuphendula.
(5) Ulwakhiwo lwe-SAGCM olwandisiweyo (RCE).
Kuyilo olulolona lungentla lwezichongi zemveli, kufuneka sijongane nenyaniso yokuba ubukhulu bomaleko wokufunxa yinto ephikisanayo yesantya sesixhobo kunye nempumelelo yomyinge.Ubunzima obuncinci boluhlu olufunxayo lunokunciphisa ixesha lokuhamba lomthwali, ngoko ke i-bandwidth enkulu inokufumaneka.Nangona kunjalo, kwangaxeshanye, ukuze ufumane ukusebenza kakuhle komyinge ophezulu, umaleko wokufunxa kufuneka ube nobukhulu obaneleyo.Isisombululo sale ngxaki sinokuba yi-resonant cavity (RCE) isakhiwo, oko kukuthi, i-Bragg Reflector esasazwayo (i-DBR) yenzelwe phantsi nangaphezulu kwesixhobo.Isibuko se-DBR sineentlobo ezimbini zezixhobo ezinesalathisi esisezantsi se-refractive kunye ne-high refractive index kwisakhiwo, kwaye ezimbini zikhula ngokutshintshana, kwaye ubukhulu boluhlu ngalunye budibana nesiganeko sokukhanya kwe-1/4 kwi-semiconductor.Isakhiwo se-resonator se-detector sinokuhlangabezana neemfuno zesantya, ubukhulu bomgca wokufunxa bunokwenziwa buncinci kakhulu, kwaye ukusebenza kwe-quantum ye-electron kwandiswa emva kokubonakaliswa okuninzi.
(6) Ubume bomda obudityanisiweyo be-waveguide (WG-APD)
Esinye isisombululo sokusombulula ukuchasana kweziphumo ezahlukeneyo zokufunxa umaleko wokutyeba kwisantya sesixhobo kunye nokusebenza kakuhle komyinge kukwazisa ubume be-waveguide obudityanisiweyo.Esi sakhiwo singena ekukhanyeni ukusuka kwicala, ngenxa yokuba umaleko wokufunxa ude kakhulu, kulula ukufumana ukusebenza kakuhle kwe-quantum, kwaye kwangaxeshanye, umaleko wokufunxa unokwenziwa ube mncinci kakhulu, unciphise ixesha lokuhamba lomthwali.Ke ngoko, esi sakhiwo sisombulula ukuxhomekeka okwahlukileyo kwe-bandwidth kunye nokusebenza kakuhle kwingqimba ye-absorption layer, kwaye kulindeleke ukuba kufezekiswe izinga eliphezulu kunye ne-APD ephezulu ye-quantum.Inkqubo ye-WG-APD ilula kunaleyo ye-RCE APD, ephelisa inkqubo enzima yokulungiselela isibuko se-DBR.Ke ngoko, inokwenzeka ngakumbi kwintsimi esebenzayo kwaye ifanelekile kuqhagamshelo lwe-optical yendiza eqhelekileyo.
3. Isiphelo
Ukuphuhliswa kwe-avalancheifotodetectorizixhobo kunye nezixhobo zijongwa kwakhona.Amazinga e-electron kunye nomgodi wokungqubuzana kwe-ionization yezinto ze-InP zisondele kwezo ze-InAlAs, ezikhokelela kwinkqubo ephindwe kabini yee-symbions ze-carrier carrier, eyenza ixesha lokwakha i-avalanche lide kwaye ingxolo yanda.Xa kuthelekiswa nezinto ezicocekileyo ze-InAlAs, i-InGaAs (P) /InAlAs kunye ne-In (Al) GaAs/InAlAs izakhiwo ze-quantum zequla zinenani elongezelelweyo lokungqubana kwe-ionization coefficients, ngoko ukusebenza kwengxolo kunokutshintshwa kakhulu.Ngokumalunga nesakhiwo, i-resonator eyandisiweyo (RCE) isakhiwo se-SAGCM kunye ne-edge-coupled waveguide structure (WG-APD) ziphuhliswa ukuze kulungiswe ukuphikisana kwemiphumo eyahlukeneyo ye-absorption layer thickness kwi-speed yesixhobo kunye nokusebenza kakuhle kwe-quantum.Ngenxa yokuntsonkotha kwenkqubo, ukusetyenziswa ngokupheleleyo kwezi zakhiwo zibini kufuneka kuphononongwe ngakumbi.
Ixesha lokuposa: Nov-14-2023