Isixhobo sokubona i-avalanche se-SPAD esine-photon enye

I-SPADisixhobo sokubona i-avalanche esine-photon enye

Xa kwaqaliswa okokuqala izinzwa ze-SPAD photodetector, zazisetyenziswa kakhulu kwiimeko zokufumanisa ukukhanya okuphantsi. Nangona kunjalo, ngokukhula kokusebenza kwazo kunye nophuhliso lweemfuno zendawo,Isixhobo sokubona ifoto se-SPADIzinzwa ziye zasetyenziswa ngakumbi kwiimeko zabathengi ezifana neerada zeemoto, iirobhothi, kunye neenqwelo-moya ezingenabantu. Ngenxa yobuntununtunu bayo obuphezulu kunye neempawu zengxolo ephantsi, isinzwa se-SPAD photodetector siye saba lukhetho olufanelekileyo lokufikelela ekuqondeni ubunzulu obuphezulu kunye nemifanekiso engaphantsi kokukhanya.

Ngokungafaniyo nezinzwa zemifanekiso zeCMOS zemveli (CIS) ezisekelwe kwiindibano zePN, isakhiwo esiphambili seSPAD photodetector yi-avalanche diode esebenza kwimo yeGeiger. Ngokwembono yeendlela ezibonakalayo, ubunzima beSPAD photodetector buphezulu kakhulu kunobo bezixhobo zePN junction. Oku kubonakala kakhulu kwinto yokuba phantsi kwe-high reverse bias, kusenokwenzeka ukuba ibangele iingxaki ezifana nokufakwa kwezithwali ezingalinganiyo, iziphumo ze-thermal electron, kunye nemisinga ye-tunneling encediswa ziimeko ze-defect. Ezi mpawu ziyenza ijongane nemingeni enzima kumanqanaba oyilo, inkqubo, kunye nolwakhiwo lwesekethe.

Iiparameters zokusebenza eziqhelekileyoIsixhobo sokubona i-avalanche ye-SPADziquka Ubungakanani bePixel (Ubungakanani bePixel), ingxolo yokubala emnyama (DCR), amathuba okubona ukukhanya (PDE), ixesha elifileyo (Ixesha elifileyo), kunye nexesha lokuphendula (Ixesha lokuphendula). Ezi parameters zichaphazela ngokuthe ngqo ukusebenza kwe-SPAD avalanche photodetector. Umzekelo, izinga lokubala emnyama (DCR) liyiparameter ephambili yokuchaza ingxolo yokubala, kwaye i-SPAD kufuneka igcine i-bias ephezulu kunokwahlulwa ukuze isebenze njenge-single-photon detector. Amathuba okubona ukukhanya (PDE) amisela uvakalelo lwe-SPAD.isixhobo sokubona ifoto se-avalanchekwaye ichaphazeleka bubunzulu kunye nokusasazwa kwentsimi yombane. Ukongeza, i-DeadTime lixesha elifunekayo ukuze i-SPAD ibuyele kwimeko yayo yokuqala emva kokuba iqaliswe, nto leyo echaphazela izinga eliphezulu lokubhaqwa kwe-photon kunye nobubanzi obuguqukayo.

Kwindlela yokusebenza kakuhle kwezixhobo ze-SPAD, ubudlelwane phakathi kwemilinganiselo yokusebenza ephambili ngumceli mngeni omkhulu: umzekelo, i-pixel miniaturization ikhokelela ngokuthe ngqo ekuncipheni kwe-PDE, kwaye ukuxinana kwamacandelo ombane omda okubangelwa yi-miniaturization yobukhulu kuya kubangela ukwanda okukhulu kwe-DCR. Ukunciphisa ixesha elifileyo kuya kubangela ingxolo emva kokuphazamiseka kwaye konakalise ukuchaneka kwexesha. Ngoku, isisombululo esiphambili sifikelele kwinqanaba elithile lokuphucula ngokubambisana ngeendlela ezifana ne-DTI/protection loop (ukunciphisa i-crosstalk kunye nokunciphisa i-DCR), ukulungiswa kwe-pixel optical, ukungeniswa kwezinto ezintsha (i-SiGe avalanche layer enhancing infrared response), kunye neesekethe ezisebenzayo ezihlanganisiweyo ezinemilinganiselo emithathu.