Uhlobo lweidivayisi ye-photodetectorisakhiwo
Isithwebuli sezithombeiyidivayisi eguqula isignali ye-optical ibe isignali kagesi, ukwakheka kwayo kanye nezinhlobonhlobo, ingahlukaniswa ikakhulukazi ngezigaba ezilandelayo:
(1) I-Photoconductive photodetector
Uma amadivaysi e-photoconductive evezwa ekukhanyeni, inkampani yenethiwekhi ekhiqizwe izithombe inyusa ukusebenza kwayo futhi inciphise ukumelana kwayo. Abathwali abajabulile ekushiseni kwegumbi bahamba ngendlela eqondisayo ngaphansi kwesenzo sensimu kagesi, ngaleyo ndlela bakhiqize umsinga. Ngaphansi kwesimo sokukhanya, ama-electron ajabule futhi ukuguquka kwenzeka. Ngesikhathi esifanayo, bahamba ngaphansi kwesenzo senkundla kagesi ukuze benze i-photocurrent. Izithwali ezikhiqizwe ngezithombe eziwumphumela zandisa ukuqhutshwa kwedivayisi futhi ngaleyo ndlela zinciphise ukumelana. Ama-Photoconductive photodetectors ngokuvamile abonisa ukuzuza okuphezulu nokusabela okukhulu ekusebenzeni, kodwa awakwazi ukuphendula kumasiginali we-optical frequency, ngakho-ke isivinini sokuphendula sihamba kancane, okukhawulela ukusetshenziswa kwamadivayisi e-photoconductive kwezinye izici.
(2)I-PN photodetector
Isitholi sesithombe se-PN sakhiwe ukuxhumana phakathi kwempahla ye-semiconductor yohlobo lwe-P kanye ne-N-type semiconductor material. Ngaphambi kokwakhiwa kokuxhumana, izinto ezimbili zisesimweni esihlukile. Ileveli ye-Fermi ku-semiconductor yohlobo lwe-P iseduze konqenqema lwebhendi ye-valence, kuyilapho ileveli ye-Fermi ku-semiconductor yohlobo lwe-N iseduze nomphetho webhendi yokuqhuba. Ngesikhathi esifanayo, izinga le-Fermi lezinto zohlobo lwe-N emaphethelweni ebhendi yokuqhuba lihanjiswa ngokuqhubekayo kuze kube yilapho izinga le-Fermi lezinto ezimbili lisesimweni esifanayo. Ukuguqulwa kwesikhundla sebhendi yokuqhuba kanye nebhendi ye-valence nakho kuhambisana nokugoba kwebhendi. I-PN junction iyalingana futhi inezinga elifanayo le-Fermi. Kusukela kusici sokuhlaziywa kwenkampani yenethiwekhi, iningi lezinkampani zokushaja ezintweni zohlobo lwe-P ziyizimbobo, kuyilapho iningi labathwali beshaja ezintweni zohlobo lwe-N zingama-electron. Lapho izinto ezimbili zithintana, ngenxa yomehluko ekugxiliseni kwenkampani yenethiwekhi, ama-electron akuzinto zohlobo lwe-N azosabalalisa ohlotsheni lwe-P, kuyilapho ama-electron akuzinto zohlobo lwe-N azosakazeka ngokuphambene nezimbobo. Indawo enganxeshezelwanga eshiywe ukusabalalisa kwama-electron kanye nezimbobo izokwakha insimu kagesi eyakhelwe ngaphakathi, futhi inkambu kagesi eyakhelwe ngaphakathi izothambekela ukukhukhuleka kwe-carrier, futhi isiqondiso se-Drift siphambene nje nendawo yokusabalalisa, okusho ukuthi ukwakheka kwenkundla kagesi eyakhelwe ngaphakathi kuvimbela ukusabalala kwabathwali, futhi kukhona kokubili ukuhlakazeka nokukhukhuleka ngaphakathi kwendawo yokuhlangana ye-PN kuze kube yilapho izinhlobo ezimbili zokunyakaza zilingana, ukuze ukugeleza kwenkampani yenethiwekhi emile kube yiziro. Ibhalansi eguqukayo yangaphakathi.
Lapho ukuhlangana kwe-PN kuvezwa emisebeni yokukhanya, amandla e-photon adluliselwa kusithwali, futhi isithwali sesithombe esikhiqizwe, okungukuthi, ipheya ye-photogenerated electron-hole, iyakhiqizwa. Ngaphansi kwesenzo senkambu kagesi, i-electron kanye nembobo drift iye endaweni engu-N kanye nesifunda esingu-P ngokulandelanayo, futhi ukukhukhuleka okuqondile kwenkampani yenethiwekhi ekhiqizwe izithombe kukhiqiza i-photocurrent. Lona umgomo oyisisekelo we-PN junction photodetector.
(3)I-PIN photodetector
I-Pin photodiode iyimpahla yohlobo lwe-P kanye nempahla yohlobo lwe-N phakathi kongqimba lwe-I, ungqimba lwe-I lwento ngokuvamile luyi-intrinsic noma i-low-doping material. Indlela yayo yokusebenza ifana ne-PN junction, lapho ukuhlangana kwe-PIN kuvezwa emisebeni yokukhanya, i-photon idlulisela amandla ku-electron, ikhiqiza izithwali zokushaja ezenziwe ngezithombe, futhi inkambu kagesi yangaphakathi noma inkambu kagesi yangaphandle izohlukanisa imbobo ye-electron-photogenerated. amapheya kungqimba yokuncipha, futhi abathwali beshaja abakhukhulekayo bazokwakha i-current kusekethe yangaphandle. Indima edlalwa ungqimba I ukukhulisa ububanzi bongqimba lokuwohloka, futhi ungqimba ngizoba ngokuphelele ungqimba lokuncipha ngaphansi kwe-voltage enkulu yokuchema, futhi amapheya e-electron-hole akhiqiziwe azohlukaniswa ngokushesha, ngakho-ke isivinini sokuphendula I-PIN junction photodetector ivamise ukushesha kunaleso se-PN junction detector. Izithwali ezingaphandle kwesendlalelo se-I nazo ziqoqwa yisendlalelo sokuncipha ngokunyakaza kokusabalalisa, kwakheka i-diffusion current. Ugqinsi lwe-I layer ngokuvamile luncane kakhulu, futhi inhloso yalo ukuthuthukisa ijubane lokuphendula lomtshina.
(4)I-APD photodetectori-avalanche photodiode
Indlela yei-avalanche photodiodeiyafana naleyo ye-PN junction. Isithwebuli sesithombe se-APD sisebenzisa ukuhlangana kwe-PN ene-doped kakhulu, i-voltage yokusebenza esekelwe ekutholweni kwe-APD inkulu, futhi uma ukuchema okuhlanekezela okukhulu kwengezwa, ukungqubuzana kwe-ionization nokuphindaphindeka kwe-avalanche kuzokwenzeka ngaphakathi kwe-APD, futhi ukusebenza komtshina kukhula i-photocurrent. Uma i-APD ikumodi ye-reverse bias, inkambu kagesi isendlalelo sokuwohloka izoba namandla kakhulu, futhi izithwali ezenza izithombe ezikhiqizwe ukukhanya zizohlukaniswa ngokushesha futhi zikhukhulwe ngokushesha ngaphansi kwesenzo senkambu kagesi. Kukhona ithuba lokuthi ama-electron azoshayisana neletisi phakathi nale nqubo, okubangele ukuthi ama-electron akulethisi abe ionized. Le nqubo iyaphindwa, futhi ama-ion ionized ku-lattice aphinde angqubuzane ne-lattice, okwenza inani labathwali be-charge ku-APD likhule, okuholela ekubeni khona kwamanje okukhulu. Yile ndlela eyingqayizivele yomzimba ngaphakathi kwe-APD lapho izitholi ezisekelwe ku-APD ngokuvamile zibe nezici zesivinini sokuphendula esisheshayo, ukuzuza kwenani elikhulu lamanje kanye nokuzwela okuphezulu. Uma kuqhathaniswa ne-PN junction kanye ne-PIN junction, i-APD inesivinini sokuphendula esisheshayo, okuyisivinini sokuphendula esisheshayo phakathi kwamashubhu amanje azwelayo.
(5) Isithwebuli sesithombe se-Schottky junction
Isakhiwo esiyisisekelo se-photodetector ye-Schottky junction yi-diode ye-Schottky, izici zayo zikagesi zifana nalezo ze-PN junction ezichazwe ngenhla, futhi inokuqhutshwa kwe-unidirectional ene-positive conduction kanye ne-reverse cut-off. Lapho insimbi enomsebenzi ophezulu kanye ne-semiconductor enokuxhumana kwefomu lomsebenzi ophansi, isithiyo se-Schottky siyakhiwa, futhi ukuhlangana okubangelwayo kuba ukuhlangana kwe-Schottky. Indlela eyinhloko icishe ifane ne-PN junction, ithatha ama-semiconductors ohlobo lwe-N njengesibonelo, lapho izinto ezimbili zenza ukuxhumana, ngenxa yokugxila okuhlukene kwama-electron wezinto ezimbili, ama-electron aku-semiconductor azosakazekela ohlangothini lwensimbi. Ama-electron ahlakazekile anqwabelana ngokuqhubekayo ekugcineni kwensimbi, ngaleyo ndlela acekele phansi ukungathathi hlangothi kukagesi kwasekuqaleni kwensimbi, akhe insimu kagesi eyakhelwe ngaphakathi esuka ku-semiconductor iye ensimbi endaweni yokuxhumana, futhi ama-electron azokhukhuleka ngaphansi kwesenzo se-electronics. inkambu kagesi yangaphakathi, kanye nokunyakaza kokusabalalisa nokukhukhuleka komthwali kuzokwenziwa ngesikhathi esisodwa, ngemva kwesikhathi esithile ukuze kufinyelele ukulingana okuguquguqukayo, futhi ekugcineni kwakhiwe ukuhlangana kwe-Schottky. Ngaphansi kwezimo zokukhanya, isifunda sokuvimbela sidonsa ngokuqondile ukukhanya futhi sikhiqize amapheya e-electron-hole, kuyilapho abathwali bezithombe abakhiqizwe izithombe ngaphakathi kwendawo yokuhlangana ye-PN badinga ukudlula endaweni yokusabalalisa ukuze bafinyelele endaweni yokuhlangana. Uma kuqhathaniswa ne-PN junction, i-photodetector esekelwe ku-Schottky junction inesivinini sokuphendula esisheshayo, futhi isivinini sokuphendula singafinyelela ngisho nezinga lika-ns.
Isikhathi sokuthumela: Aug-13-2024