Chowunikira zithunzi cha SPAD single-photon avalanche

SPADchowunikira zithunzi cha avalanche cha single-photon

Pamene masensa a SPAD photodetector anayamba kugwiritsidwa ntchito, ankagwiritsidwa ntchito makamaka pazochitika zodziwika bwino. Komabe, chifukwa cha kusintha kwa magwiridwe antchito awo komanso kukula kwa zofunikira pa malo,Chowunikira zithunzi cha SPADMasensa akhala akugwiritsidwa ntchito kwambiri pazochitika za ogula monga ma radar a magalimoto, maloboti, ndi magalimoto amlengalenga opanda anthu. Chifukwa cha mphamvu zake zogwira ntchito komanso phokoso lochepa, sensa ya SPAD photodetector yakhala chisankho chabwino kwambiri chofikira kuzindikira kwakuya kolondola komanso kujambula zithunzi zopepuka.

Mosiyana ndi masensa achikhalidwe a CMOS (CIS) ozikidwa pa ma PN junctions, kapangidwe kake ka SPAD photodetector ndi avalanche diode yomwe imagwira ntchito mu Geiger mode. Kuchokera pamalingaliro a njira zakuthupi, zovuta za SPAD photodetector ndizokwera kwambiri kuposa za zida za PN junction. Izi zimawonekera makamaka chifukwa chakuti pansi pa reverse bias yayikulu, nthawi zambiri zimayambitsa mavuto monga kulowetsa zonyamulira zosalinganika, zotsatira za ma elekitironi otentha, ndi mafunde a tunneling omwe amathandizidwa ndi zilema. Makhalidwe amenewa amachititsa kuti ikumane ndi zovuta zazikulu pakupanga, njira, ndi kapangidwe ka ma circuit.

Magawo ofanana a magwiridwe antchito aChowunikira chithunzi cha SPAD avalanchekuphatikiza Kukula kwa Pixel (Kukula kwa Pixel), phokoso la mdima (DCR), kuthekera kozindikira kuwala (PDE), Nthawi yakufa (Nthawi Yomwalira), ndi Nthawi Yoyankha (Nthawi Yoyankha). Magawo awa amakhudza mwachindunji magwiridwe antchito a SPAD avalanche photodetector. Mwachitsanzo, mdima wowerengera (DCR) ndi gawo lofunikira kwambiri pofotokozera phokoso la detector, ndipo SPAD iyenera kukhala ndi kusiyana kwakukulu kuposa kusweka kuti igwire ntchito ngati detector ya single-photon. Kuthekera kozindikira kuwala (PDE) kumatsimikizira kukhudzidwa kwa SPAD.chowunikira zithunzi cha chipale chofewandipo imakhudzidwa ndi mphamvu ndi kufalikira kwa mphamvu ya magetsi. Kuphatikiza apo, DeadTime ndi nthawi yomwe imafunika kuti SPAD ibwerere ku mkhalidwe wake woyamba itatha kuyatsidwa, zomwe zimakhudza kuchuluka kwa kuzindikira kwa photon ndi dynamic range.

Pakukonza magwiridwe antchito a zida za SPAD, ubale woletsa pakati pa magawo ofunikira a magwiridwe antchito ndi vuto lalikulu: mwachitsanzo, kuchepera kwa pixel kumapangitsa kuti PDE ichepetse, ndipo kuchuluka kwa magetsi m'mphepete chifukwa cha kuchepera kwa kukula kudzapangitsanso kuwonjezeka kwakukulu kwa DCR. Kuchepetsa nthawi yotayika kudzayambitsa phokoso pambuyo pa kugwedezeka ndikuchepetsa kulondola kwa nthawi. Tsopano, yankho lamakono lakwaniritsa kukhathamiritsa kogwirizana kudzera mu njira monga DTI/protection loop (kuletsa crosstalk ndi kuchepetsa DCR), kukhathamiritsa kwa pixel optical, kuyambitsa zipangizo zatsopano (SiGe avalanche layer enhancing infrared response), ndi ma three-dimensional stacked active quenching circuits.