Uhlobo lweidivayisi yokubona izithombeisakhiwo
Isitholi sezithombeiyidivayisi eguqula isignali yokukhanya ibe isignali kagesi, isakhiwo sayo kanye nokuhlukahluka kwayo, ingahlukaniswa kakhulu ngezigaba ezilandelayo:
(1) Isitholi se-photoconductor esisebenza nge-photoconductor
Uma amadivayisi asebenzisa i-photoconductor evezwa ekukhanyeni, isithwali esikhiqizwa yi-photoconductor sandisa ukuhanjiswa kwawo futhi sinciphise ukumelana kwawo. Abathwali abakhuthazwa ekushiseni kwegumbi bahamba ngendlela eqondisiwe ngaphansi kwesenzo sensimu kagesi, ngaleyo ndlela bakhiqize ugesi. Ngaphansi kwesimo sokukhanya, ama-electron ayakhuthazwa futhi kwenzeka ushintsho. Ngesikhathi esifanayo, azulazula ngaphansi kwesenzo sensimu kagesi ukuze akhe ugesi we-photocurrent. Abathwali abakhiqizwa yi-photoconductor abaphumayo bandisa ukuhanjiswa kwedivayisi futhi ngaleyo ndlela banciphise ukumelana. Ama-photodetector e-Photoconductor avame ukubonisa inzuzo ephezulu kanye nokuphendula okukhulu ekusebenzeni, kodwa awakwazi ukuphendula ezimpawini ezibonakalayo ezivame kakhulu, ngakho-ke ijubane lokuphendula lihamba kancane, okunciphisa ukusetshenziswa kwamadivayisi asebenzisa i-photoconductor kwezinye izici.
(2)Isitholi sezithombe se-PN
I-PN photodetector yakhiwa ukuxhumana phakathi kwezinto ze-semiconductor zohlobo lwe-P nezinto ze-semiconductor zohlobo lwe-N. Ngaphambi kokuba kuhlanganiswe ukuxhumana, izinto ezimbili zisesimweni esihlukile. Izinga le-Fermi ku-semiconductor yohlobo lwe-P liseduze nomngcele webhendi ye-valence, kuyilapho izinga le-Fermi ku-semiconductor yohlobo lwe-N liseduze nomngcele webhendi yokuqhuba. Ngesikhathi esifanayo, izinga le-Fermi lezinto ze-N ezisemaphethelweni ebhendi yokuqhuba liyaqhubeka lishintsha liye phansi kuze kube yilapho izinga le-Fermi lezinto ezimbili lisesimweni esifanayo. Ukushintsha kwesikhundla sebhendi yokuqhuba kanye nebhendi ye-valence nakho kuhambisana nokugoba kwebhendi. I-PN junction isezingeni elilinganayo futhi inezinga le-Fermi elifanayo. Kusukela esicini sokuhlaziywa kwe-charge carrier, iningi le-charge carrier ezintweni ze-P ziyimigodi, kuyilapho iningi le-charge carrier ezintweni ze-N zingama-electron. Lapho izinto ezimbili zixhumana, ngenxa yomehluko ekugxilweni kwe-carrier, ama-electron ezintweni ze-N azosakazeka aye ku-P, kuyilapho ama-electron ezintweni ze-N azosakazeka ngendlela ephambene nemigodi. Indawo engakhokhelwa eshiywe ukusabalala kwama-electron kanye nezimbobo izokwakha insimu kagesi eyakhelwe ngaphakathi, kanti insimu kagesi eyakhelwe ngaphakathi izothambekela ekukhukhuleni komthwali, futhi isiqondiso sokukhukhuleka siphambene nesiqondiso sokukhukhuleka, okusho ukuthi ukwakheka kwensimu kagesi eyakhelwe ngaphakathi kuvimbela ukusabalala kwabathwali, futhi kukhona kokubili ukusabalala kanye nokukhukhuleka ngaphakathi kwe-PN junction kuze kube yilapho izinhlobo ezimbili zokunyakaza zilinganisiwe, ukuze ukugeleza komthwali omile kube zero. Ibhalansi yangaphakathi enamandla.
Uma indawo yokuhlangana kwe-PN ivezwa emisebeni yokukhanya, amandla e-photon adluliselwa endaweni yokuphatha, bese kukhiqizwa indawo yokuphatha evezwa yi-photo, okungukuthi, i-photogenerated electron-hole pair. Ngaphansi kwesenzo sensimu kagesi, i-electron kanye ne-hole kuya esifundeni se-N kanye nesifunda se-P ngokulandelana, kanti ukuzulazula okuqondiswayo kwendawo yokuphatha evezwa yi-photo kukhiqiza i-photocurrent. Lesi yisimiso esiyisisekelo se-PN junction photodetector.
(3)Isitholi sesithombe se-PIN
I-Pin photodiode iyinto yohlobo lwe-P kanye nezinto zohlobo lwe-N phakathi kwesendlalelo i-I, ungqimba lwe-I lwale nto ngokuvamile luyinto yangaphakathi noma ephansi kokusebenzisa i-doping. Indlela yayo yokusebenza ifana nokuhlangana kwe-PN, lapho ukuhlangana kwe-PIN kuvezwe emisebeni yokukhanya, i-photon idlulisela amandla ku-electron, ikhiqize izithwali zokushaja ezikhiqizwa yi-photo, futhi insimu kagesi yangaphakathi noma insimu kagesi yangaphandle izohlukanisa amabhangqa e-electron-hole akhiqizwa yi-photo kulesendlalelo sokuncipha, futhi izithwali zokushaja ezikhukhulekile zizokwakha ugesi kusekethe yangaphandle. Indima edlalwa ungqimba I ukwandisa ububanzi besendlalelo sokuncipha, kanti ungqimba I luzoba ungqimba lokuncipha ngokuphelele ngaphansi kwe-voltage enkulu ye-bias, futhi amabhangqa e-electron-hole akhiqizwayo azohlukaniswa ngokushesha, ngakho-ke isivinini sokuphendula se-PIN junction photodetector ngokuvamile sishesha kunesomshini wokuthola i-PN junction. Izithwali ezingaphandle kwesendlalelo i-I nazo ziqoqwa ungqimba lokuncipha ngokuhamba kokusabalalisa, zakha ugesi wokusabalalisa. Ubukhulu besendlalelo i-I ngokuvamile buncane kakhulu, futhi inhloso yaso ukuthuthukisa isivinini sokuphendula se-detector.
(4)Isitholi sezithombe se-APDi-photodiode yeqhwa
Indlela yokusebenzai-photodiode yeqhwaifana neye-PN junction. I-APD photodetector isebenzisa i-PN junction exutshwe kakhulu, i-voltage yokusebenza esekelwe ekutholakaleni kwe-APD inkulu, futhi lapho kufakwa i-reverse bias enkulu, i-collision ionization kanye nokuphindaphinda kwe-avalanche kuzokwenzeka ngaphakathi kwe-APD, futhi ukusebenza kwe-detector kuyanda i-photocurrent. Uma i-APD ikumodi ye-reverse bias, insimu kagesi esendlalelo sokuncipha izoba namandla kakhulu, futhi abathwali abakhiqizwa yi-photogenerated abakhiqizwe ukukhanya bazohlukaniswa ngokushesha futhi bashelele ngokushesha ngaphansi kwesenzo sensimu kagesi. Kukhona amathuba okuthi ama-electron azongena ku-lattice phakathi nale nqubo, okubangela ukuthi ama-electron ase-lattice abe yi-ionized. Le nqubo iyaphindwa, futhi ama-ion afakwe ku-lattice nawo angqubuzane ne-lattice, okubangela ukuthi inani labathwali be-charge ku-APD lande, okuholela ku-current enkulu. Yile ndlela eyingqayizivele yomzimba ngaphakathi kwe-APD ukuthi abatholi abasekelwe ku-APD ngokuvamile banezici zesivinini sokuphendula okusheshayo, inzuzo enkulu yamanje kanye nokuzwela okuphezulu. Uma kuqhathaniswa ne-PN junction kanye ne-PIN junction, i-APD inesivinini sokuphendula esisheshayo, okuyisivinini sokuphendula esisheshayo phakathi kwamashubhu amanje azwela ukukhanya.
(5) I-Schottky junction photodetector
Isakhiwo esiyisisekelo se-Schottky junction photodetector yi-Schottky diode, enezici zayo zikagesi ezifana neze-PN junction echazwe ngenhla, futhi inokuhambisa amandla okuqondisa okukodwa okunokuhambisa okuhle kanye nokunqamula emuva. Lapho insimbi enomsebenzi ophezulu kanye ne-semiconductor enomsebenzi ophansi wokusebenza yakha ukuxhumana, kwakheka isithiyo se-Schottky, futhi ukuhlangana okuphumelayo kuyi-Schottky junction. Indlela eyinhloko ifana kancane ne-PN junction, kuthathwa ama-semiconductor ohlobo lwe-N njengesibonelo, lapho izinto ezimbili zakha ukuxhumana, ngenxa yokugxila okuhlukile kwama-electron kwezinto ezimbili, ama-electron ku-semiconductor azosakazeka ohlangothini lwensimbi. Ama-electron asakazekile aqoqana njalo ekugcineni kwensimbi, ngaleyo ndlela abhubhise ukungathathi hlangothi kukagesi kokuqala kwensimbi, akha insimu kagesi eyakhelwe ngaphakathi kusuka ku-semiconductor kuya ensimbi ebusweni bokuxhumana, futhi ama-electron azokhukhuleka ngaphansi kwesenzo sensimu kagesi yangaphakathi, futhi ukusabalalisa kanye nokunyakaza kokuthwala kuzokwenziwa ngesikhathi esisodwa, ngemva kwesikhathi esithile ukuze kufinyelelwe ukulingana okuguquguqukayo, futhi ekugcineni kwakheke i-Schottky junction. Ngaphansi kwezimo zokukhanya, isifunda esivimbelayo simunca ngqo ukukhanya futhi sikhiqize ama-electron-hole pair, kuyilapho izithwali ezikhiqizwa nge-photogenerated ngaphakathi kwe-PN junction zidinga ukudlula esifundeni sokusabalalisa ukuze zifinyelele esifundeni se-junction. Uma kuqhathaniswa ne-PN junction, i-photodetector esekelwe ku-Schottky junction inesivinini sokuphendula esisheshayo, futhi isivinini sokuphendula singafinyelela ngisho nasezingeni le-ns.
Isikhathi sokuthunyelwe: Agasti-13-2024