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-electron kunye nemingxuma iya kwenza intsimi yombane eyakhelwe-ngaphakathi, kwaye intsimi yombane eyakhelwe-ngaphakathi iya kuhamba phambili kwi-carrier drift, kwaye i-drift ye-drift ichasene nje necala lokusasazwa, okuthetha ukuba ukwakheka kwendawo yombane eyakhelwe-ngaphakathi kuthintela ukusasazwa kwabathwali, kwaye kukho zombini i-dift drift ngaphakathi. intshukumo ilungelelene, ukwenzela ukuba 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 ekhanyayo, i-photon idlulisela amandla kwi-electron, ivelisa abathwali bentlawulo ye-photogenerated, kunye nentsimi yombane yangaphakathi okanye intsimi yombane yangaphandle iya kwahlula i-electron-hole pairs kwi-depletion layer, kunye ne-drifted charge carriers kwi-carrier carriers yangaphandle iya kwenza i-carrier carriers. Indima edlalwe ngumaleko I kukwandisa ububanzi umaleko wokuncipha, kwaye umaleko ndiya kuba ngokupheleleyo umaleko wokuncipha phantsi kombane omkhulu othambekele ekuthandeni, kwaye izibini eziveliswayo ze-electron-hole ziya kwahlulwa ngokukhawuleza, ngoko ke isantya sokuphendula se-PIN isiphambuka se-photodetector ngokuqhelekileyo sikhawuleza ngaphezu kweso se-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 ezixubileyo ziqokelela ngokuqhubekayo kwelinye icala lesinyithi, ngaloo ndlela zitshabalalisa ukungathathi hlangothi kombane kwentsimbi, zenza intsimi yombane eyakhelweyo ukusuka kwi-semiconductor ukuya kwintsimbi kumphezulu woqhagamshelwano, kwaye ii-electron ziya kukhukuliseka phantsi kwesenzo sentsimi yombane yangaphakathi, kwaye ukusasazwa komthwali kunye nokuhamba ngexesha elifanayo kuya kuqhutywa emva kwexesha elihambayo. ukulingana, kwaye ekugqibeleni wenze isiphambuka seSchottky. 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