Uhlobo lweisixhobo sokufotaisakhiwo
Isikhangeli seefotosisixhobo esiguqula isignali ye-optical ibe ngumqondiso wombane, ubume bayo kunye neentlobo ezahlukeneyo, zinokwahlulwa ikakhulu kwezi ndidi zilandelayo:
(1) Ifotoconductive photodetector
Xa izixhobo ze-photoconductive zibonakaliswe ekukhanyeni, i-carrier ye-photogenerated carrier iyakwandisa ukuqhutyelwa kwayo kwaye iyancipha ukuxhathisa. Abathwali abanomdla kwiqondo lokushisa kwegumbi bahamba ngendlela ehambelanayo phantsi kwesenzo sentsimi yombane, ngaloo ndlela bavelisa okwangoku. Ngaphantsi kwemeko yokukhanya, ii-electron ziyavuya kwaye utshintsho lwenzeka. Kwangaxeshanye, bakhukuliseka phantsi kwesenzo sebala lombane ukwenza i-photocurrent. Abathwali beefoto ezibangelwayo zonyusa i-conductivity yesixhobo kwaye ngaloo ndlela banciphisa ukuxhathisa. Iifotoconductive photodetectors zihlala zibonisa inzuzo ephezulu kunye nokuphendula okukhulu ekusebenzeni, kodwa azikwazi ukuphendula kwiimpawu ze-optical high-frequency, ngoko ke isantya sokuphendula sicotha, esithintela ukusetyenziswa kwezixhobo ze-photoconductive kwezinye iinkalo.
(2)PN ifotodetector
I-photodetector ye-PN yenziwe ngoqhagamshelwano phakathi kwe-P-type semiconductor material kunye ne-N-type semiconductor material. Ngaphambi kokuba uqhagamshelwano lwenziwe, izixhobo ezimbini zikwimeko eyahlukileyo. Inqanaba leFermi kwi-P-type semiconductor isondele kumda webhendi ye-valence, ngelixa inqanaba leFermi kwi-N-type semiconductor lisondele kumda webhendi yokuqhuba. Kwangaxeshanye, inqanaba leFermi lezinto zohlobo lwe-N kumda webhendi yokuqhuba iqhubeka ishenxiswa ukuya ezantsi de inqanaba leFermi lezinto ezimbini likwindawo enye. Utshintsho lwesikhundla sebhendi yokuqhuba kunye nebhendi ye-valence nayo ihamba kunye nokugoba kwebhendi. I-PN junction ikwi-equilibrium kwaye inomgangatho ofanayo weFermi. Ukusuka kwinkalo yokuhlalutya umthwali wentlawulo, uninzi lwabathwali bentlawulo kwizinto zohlobo lwe-P ziyimingxuma, ngelixa uninzi lwabathwali bentlawulo kwizinto zohlobo lwe-N ziyi-electron. Xa izinto ezimbini zidibene, ngenxa yokwahlukana kwi-concentration carrier, i-electrons kwi-N-type materials iya kusasazeka kwi-P-uhlobo, ngelixa i-electrons kwizinto zohlobo lwe-N ziya kusasazeka kwicala elichasene nemingxuma. Indawo engahlawulwanga eshiywe kukusasazwa kwee-elektroni kunye nemingxuma iya kwenza indawo yombane eyakhelweyo, kwaye indawo yombane eyakhelweyo iya kuqhuba i-carrier drift, kwaye isalathiso se-drift sichasene necala lokusasazwa, okuthetha ukuba Ukwakhiwa kwendawo yombane eyakhelweyo kuthintela ukusasazwa kwabathwali, kwaye kukho zombini ukusasazwa kunye nokukhukuliseka ngaphakathi kwe-PN junction de zibe zimbini iintlobo zentshukumo zilinganiswe, ukuze ukuhamba kwe-static carrier kube ngu-zero. Ibhalansi eguqukayo yangaphakathi.
Xa i-PN junction ibonakaliswe kwi-radiation ekhanyayo, amandla e-photon adluliselwa kumthwali, kwaye i-carrier ye-photogenerated carrier, oko kukuthi, i-photogenerated electron-hole pair, yenziwe. Ngaphantsi kwesenzo sommandla wombane, i-electron kunye ne-hole drift ukuya kummandla we-N kunye nommandla we-P ngokulandelanayo, kunye ne-directional drift ye-carrier ye-photogenerated yenza i-photocurrent. Lo ngumgaqo osisiseko we-PN ye-punction photodetector.
(3)I-PIN yokufota
I-Pin photodiode yimathiriyeli yohlobo lwe-P kunye nohlobo lwe-N phakathi kwe-I layer, umaleko we-I wemathiriyeli ngokuqhelekileyo yinto engaphakathi okanye ephantsi-doping. Indlela yokusebenza kwayo ifana ne-PN junction, xa i-PIN ye-junction ibonakaliswe kwi-radiation yokukhanya, i-photon idlulisela amandla kwi-electron, ivelisa abathwali bentlawulo ye-photogenerated, kunye nentsimi yombane yangaphakathi okanye indawo yombane yangaphandle iya kwahlula i-electron-hole ye-photogenerated. izibini kwi-depletion layer, kunye ne-drifted charge carriers ziya kwenza i-current in the circuit yangaphandle. Indima edlalwe ngumaleko I kukwandisa ububanzi bomgangatho wokuncipha, kwaye umaleko ndiya kuba ngokupheleleyo ngumaleko wokuncipha phantsi kombane omkhulu we-bias, kwaye izibini ezenziwe nge-electron-hole ziya kwahlulwa ngokukhawuleza, ngoko isantya sokuphendula I-PIN junction photodetector ikhawuleza kakhulu kunaleyo ye-PN junction detector. Abathwali abangaphandle kwe-I layer nabo baqokelelwa ngumaleko wokunciphisa ngokunyuka kwe-diffusion motion, okwenza i-diffusion current. Ubukhulu be-I layer buncinci kakhulu, kwaye injongo yayo kukuphucula isantya sokuphendula se-detector.
(4)Isixhobo sokufota seAPDi-avalanche photodiode
Inkqubo yei-avalanche photodiodeiyafana naleyo ye-PN junction. I-photodetector ye-APD isebenzisa i-PN junction edibeneyo, i-voltage yokusebenza esekelwe kwi-APD yokufumanisa inkulu, kwaye xa i-bias enkulu yongezwayo yongezwa, i-ionization ye-collision kunye nokuphindaphinda kwe-avalanche kuya kwenzeka ngaphakathi kwe-APD, kwaye ukusebenza komtshina kunyuswe photocurrent. Xa i-APD ikwimo ye-bias ye-reverse, intsimi yombane kwi-depletion layer iya kuba yomelele kakhulu, kwaye abathwali be-photogenerated abaveliswa kukukhanya baya kuhlukana ngokukhawuleza kwaye baqhube ngokukhawuleza phantsi kwesenzo sombane wombane. Kukho amathuba okuba ii-electron ziya kungqubeka kwi-lattice ngexesha lale nkqubo, okubangela ukuba ii-electron kwi-lattice zibe ionized. Le nkqubo iphinda iphindwe, kwaye i-ion ionized in the lattice iphinda idibanise ne-lattice, ebangela ukuba inani labathwali bentlawulo kwi-APD linyuke, libangele umbane omkhulu. Yile ndlela ekhethekileyo yomzimba ngaphakathi kwe-APD ukuba ii-detectors ezisekelwe kwi-APD ngokubanzi zineempawu zesantya sokuphendula ngokukhawuleza, inzuzo enkulu yangoku kunye novakalelo oluphezulu. Xa kuthelekiswa ne-PN junction kunye ne-PIN junction, i-APD inesantya sokuphendula ngokukhawuleza, eyona nto isantya sokuphendula ngokukhawuleza phakathi kweetyhubhu ze-photosensitive zangoku.
(5) I-schottky junction photodetector
Isakhiwo esisisiseko se-Schottky junction photodetector yi-diode ye-Schottky, eneempawu zombane ezifana nezo ze-PN junction echazwe ngasentla, kwaye ine-conductivity ye-unidirectional kunye ne-positive conduction kunye ne-reverse cut-off. Xa isinyithi esinomsebenzi ophezulu kunye ne-semiconductor enoqhagamshelwano oluphantsi lwefomu yomsebenzi, umqobo we-Schottky wenziwa, kwaye ukudibanisa okubangelwa yi-junction ye-Schottky. Eyona ndlela iphambili ifana nje ne-PN junction, ithatha i-N-type semiconductors njengomzekelo, xa izinto ezimbini zenza uqhagamshelwano, ngenxa yobuninzi bee-electron ezahlukeneyo zezinto ezimbini, i-electron kwi-semiconductor iya kusasaza kwicala lesinyithi. Ii-electron ezisasazekileyo ziqokelela ngokuqhubekayo kwelinye icala lesinyithi, ngaloo ndlela zitshabalalisa ukungathathi hlangothi kombane kwentsimbi, zenza indawo yombane eyakhelweyo ukusuka kwi-semiconductor ukuya kwintsimbi kumphezulu woqhagamshelwano, kwaye ii-electron ziya kukhukuliseka phantsi kwesenzo sombane. intsimi yombane yangaphakathi, kunye ne-carrier's diffusion kunye ne-drift motion iya kuqhutywa ngaxeshanye, emva kwexesha elithile lokufikelela kwi-equilibrium eguquguqukayo, kwaye ekugqibeleni wenze i-junction ye-Schottky. Ngaphantsi kweemeko zokukhanya, ummandla wesithintelo uthatha ngokuthe ngqo ukukhanya kwaye uvelise izibini ze-electron-hole, ngelixa abathwali be-photogenerated ngaphakathi kwe-PN junction kufuneka badlule kummandla we-diffusion ukufikelela kummandla we-junction. Xa kuthelekiswa ne-PN junction, i-photodetector esekelwe kwi-Schottky junction inesantya sokuphendula ngokukhawuleza, kwaye isantya sokuphendula sinokufikelela kwinqanaba le-ns.
Ixesha lokuposa: Aug-13-2024