Kev Siv Tshuab Los Tsim Lub Koob Yees Duab Sensor Hauv Smartphones
Kev tsim cov koob yees duab ntawm xov tooj ntse hauv kaum xyoo dhau los no tau zoo kawg nkaus. Cov duab uas ib zaug tsuas yog "zoo txaus rau kev sau ntawv" tam sim no muaj peev xwm mus txog qhov zoo ntawm cov koob yees duab tshwj xeeb hauv ntau yam xwm txheej. Kev nce qib no tsis yog tsuas yog tsav los ntawm cov software ua cov duab xwb tab sis kuj los ntawm cov thev naus laus zis tsim cov koob yees duab sensors - cov khoom tseem ceeb uas hloov lub teeb mus rau hauv cov teeb liab hluav taws xob. Tom qab lub koob yees duab nyias nyias muaj cov txheej txheem tsim khoom semiconductor nyuaj, raug siab, thiab hloov pauv tas li kom tau raws li cov teeb meem ntawm qhov me me, kev siv hluav taws xob tsawg, thiab cov duab zoo.
1. Lub luag haujlwm ntawm cov sensors thiab cov qauv hauv kev siv tshuab koob yees duab ntawm xov tooj ntawm tes
Cov koob yees duab ntawm lub xov tooj ntse feem ntau yog siv CMOS (Complementary Metal-Oxide Semiconductor). Piv rau cov CCD sensors uas ib zaug nrov, CMOS siv hluav taws xob ntau dua, nyeem tau sai dua, thiab yooj yim dua rau kev sib koom ua ke nrog cov txheej txheem ua haujlwm ntawm tib lub chip. Cov qauv tsav tsheb tsim kho tshiab ntawm lub xov tooj ntse sensor suav nrog: kev daws teeb meem ntau dua (txog li kaum lossis ntau pua megapixels), kev ua haujlwm zoo dua hauv qhov kaj tsawg, kev muaj peev xwm ua yeeb yaj kiab siab, HDR tiag tiag, autofocus ceev, thiab kev txhawb nqa rau kev thaij duab computational.
Tag nrho cov no xav tau cov chaw tsim khoom siv lub zog sensor kom ua kom zoo dua cov qauv pixel, cov ntaub ntawv, cov txheej txheem lithography, cov qauv tsim hluav taws xob, thiab txawm tias txoj kev uas lawv teeb tsa cov khaubncaws sab nraud povtseg kom tswj tau qhov nyias thaum txhim kho kev ua tau zoo.
2. Cov qauv yooj yim ntawm CMOS sensor: los ntawm photons mus rau cov ntaub ntawv
Hais yooj yim xwb, txhua lub pixel ntawm lub CMOS sensor muaj ib cheeb tsam photodiode los ntes lub teeb thiab cov transistors me me los nyeem thiab ua kom lub teeb ci ntsa iab. Thaum cov photons nkag mus, lub photodiode tsim cov electrons (lub zog hluav taws xob) sib npaug rau lub zog ntawm lub teeb. Lub zog no ces nyeem los ntawm lub voj voog nyeem ntawv, hloov mus ua cov ntaub ntawv digital los ntawm ADC (Analog-to-Digital Converter), thiab tom qab ntawd ua tiav rau hauv daim duab.
Txawm li cas los xij, qhov kev tsim qauv siv tau yooj yim dua: txhua lub pixel yuav tsum txo qhov suab nrov, nce qhov ntau thiab tsawg ntawm lub teeb, tiv thaiv kev sib txuas lus (kev xau ntawm lub teeb lossis them rau cov pixels nyob sib ze), thiab tswj hwm qhov rhiab heev txawm tias qhov loj ntawm pixel txuas ntxiv mus.
3. Theem tsim khoom wafer: lub hauv paus ntawm kev tsim khoom sensor
Kev tsim cov koob yees duab sensor pib nrog silicon wafers, ib yam li lwm yam kev lag luam semiconductor. Cov txheej txheem tseem ceeb suav nrog:
1. Kev ua kom tawv nqaij thiab cov zaj duab xis nyias nyias
Lub wafer yog coated nrog ib tug insulating los yog conducting khoom (piv txwv li SiO₂, poly-silicon, tej yam hlau) siv ib tug txheej txheem xws li CVD (Chemical Vapor Deposition) los yog PVD (Physical Vapor Deposition).
2. Kev thaij duab los ntawm duab
Cov qauv ntawm lub voj voog thiab cov qauv pixel yog "luam tawm" siv photoresist thiab raug lub teeb los ntawm lub ntsej muag. Cov txheej txheem thev naus laus zis me dua, qhov tseeb dua ntawm lithography xav tau.
3. Kev kos duab
Qee qhov ntawm cov txheej raug tshem tawm los tsim cov qauv, los ntawm kev etching ntub lossis etching qhuav (plasma).
4. Kev siv tshuaj doping / ion implantation
Qee cov ions raug cog rau hauv silicon los tsim cov cheeb tsam N thiab P, uas yog qhov tsim nyog rau cov photodiodes thiab transistors ua haujlwm raws li cov lus qhia.
5. Kev sib txuas ua ke thiab kev sib txuas
Cov hlau taug kev tau tsim los txuas cov transistors, nco, thiab cov blocks ua haujlwm hauv lub chip.
Hauv cov koob yees duab sensors, kev tsim pixel tsis yog tsuas yog tsom mus rau transistors xwb tab sis kuj tseem tsom mus rau kev ua kom zoo dua cov photodiodes thiab cov qauv micro-optical saum toj no lawv. Qhov kev sib tw yog xyuas kom meej tias cov khoom siv hluav taws xob thiab cov khoom siv kho qhov muag ua haujlwm sib haum xeeb hauv thaj chaw me me.
4. Backside Illumination (BSI): kev hloov pauv hauv kev rhiab heev
Ib qho ntawm cov kev hloov tshiab tseem ceeb hauv cov sensors smartphone yog BSI (Backside Illumination). Hauv cov sensors ib txwm muaj (Frontside Illumination/FSI), lub teeb nkag los ntawm tib sab li cov txheej hlau thiab transistors. Yog li ntawd, qee lub teeb raug thaiv los ntawm cov xov hlau thiab circuitry, txo qhov rhiab heev.
Hauv BSI, cov wafer raug ua kom lub teeb nkag los ntawm "rov qab" (sab tsis muaj kev sib txuas). Qhov no ua tiav los ntawm kev ua kom cov wafer nyias thiab txav cov kab sib txuas mus rau sab tod. Qhov tshwm sim:
- ntau lub teeb mus txog lub photodiode,
- kev ua tau zoo dua thaum tsis muaj teeb pom kev zoo,
- kev ua haujlwm quantum siab dua,
- tsim nyog rau cov pixels me me.
Cov txheej txheem BSI xav tau kev tswj hwm cov khoom siv thiab tshuaj lom neeg nruj thaum lub sijhawm wafer thinning, vim tias qhov tuab dhau tuaj yeem txo cov txiaj ntsig (tus nqi ua tiav ntawm kev tsim khoom) lossis ua rau wafer yooj yim tawg.
5. Stacked CMOS: stacked kom ceev thiab nplua nuj cov haujlwm
Yuav kom nce qhov ceev thiab ntxiv cov yam ntxwv yam tsis nce qhov loj, kev lag luam tab tom siv cov sensors sib dhos. Lub tswv yim: cais cov pixel txheej thiab cov logic txheej rau ntawm cov wafers sib cais, tom qab ntawd txuas lawv siv cov thev naus laus zis sib txuas ua ke heev (piv txwv li, hybrid bonding lossis TSV—Through-Silicon Via).
Cov txiaj ntsig ntawm stacked CMOS:
- Kev nyeem ntawv sai dua, tsim nyog rau cov yeeb yaj kiab ceev ceev, cov duab tawg, thiab txo qhov dov.
- Ntau qhov kev xav thiab lub cim xeeb tuaj yeem ntxiv tau (piv txwv li buffers / DRAM ntawm qee qhov kev tsim qauv) yam tsis muaj kev txi thaj chaw pixel.
- Kev ua haujlwm ntawm on-sensor xws li kev ua haujlwm ntau qhov kev pom HDR sai dua lossis kev ua haujlwm autofocus zoo dua.
Hauv kev tsim khoom, kev sib dhos wafer xav tau qhov tseeb heev. Cov teeb meem tseem ceeb yog kev tswj hwm qhov zoo ntawm kev sib txuas, txo qhov tsis kam, nce cov txiaj ntsig, thiab tswj hwm cov nqi tsim khoom qis.
6. Kev siv tshuab Pixel: micro-lens, CFA, thiab kev cais tawm
Saum toj no lub photodiode, muaj cov khoom siv kho qhov muag me me tseem ceeb heev:
- Microlens: lub lens me me saum toj ntawm txhua pixel kom "sau" lub teeb rau ntawm thaj chaw nquag ntawm photodiode. Ntawm cov xov tooj ntse nrog cov koob yees duab me me, microlenses pab ua kom muaj ntau lub teeb kom ncav cuag lub pixel.
– Xim Lim Array (CFA): ib lub lim xim (feem ntau yog Bayer qauv lossis ntau yam ntawm nws) uas tso cai rau lub sensor kom paub qhov txawv ntawm cov xim. CFAs yog tsim los ntawm kev tso thiab ua qauv ntawm cov khoom siv polymer xim.
– Kev Rho Tawm Qhov Sib Sib Zog (DTI): qhov chaw rho tawm uas muaj cov khoom rwb thaiv kom tiv thaiv kev sib tshuam ntawm cov pixels. DTI tseem ceeb heev thaum qhov loj ntawm pixel txo qis thiab qhov apertures ntawm lub lens nce ntxiv.
Kev sib xyaw ua ke ntawm cov microlenses, CFA, thiab DTI yog tus choj ntawm lub ntiaj teb kho qhov muag thiab lub ntiaj teb hluav taws xob. Cov yuam kev me me hauv qhov tuab ntawm txheej, qhov chaw, lossis kev sib xws tuaj yeem cuam tshuam rau qhov tseeb ntawm xim, qhov ntse, thiab suab nrov.
7. Kev Tshawb Fawb Txog Theem (PDAF) thiab cov pixels tshwj xeeb
Ntau lub xov tooj ntse niaj hnub no siv PDAF (Phase Detection Autofocus) ntawm lub sensor. Qhov no suav nrog cov pixels tshwj xeeb, lossis thaj chaw, uas tau txais lub teeb los ntawm cov qhov tshwj xeeb ntawm lub lens aperture thiab xam qhov sib txawv ntawm theem kom txiav txim siab qhov kev taw qhia thiab qhov dav ntawm kev hloov kho qhov tsom mus rau.
Kev siv PDAF xav tau CFA thiab microlens tsim sib txawv rau cov pixels tshwj xeeb, lossis cov qauv micromasking. Qhov no ntxiv rau qhov nyuaj ntawm kev tsim khoom vim tias tsis yog txhua lub pixels zoo ib yam. Qhov kev sib tw yog xyuas kom meej tias PDAF pixels tsis cuam tshuam rau qhov zoo ntawm daim duab (piv txwv li, qhia txog cov khoom cuav), thaum tswj qhov tseeb ntawm kev tsom mus rau.
8. HDR, kev hloov pauv ob npaug, thiab kev tsim qauv nyeem tawm
Ntxiv rau kev txhim kho "kev ntes lub teeb", kev tsim cov sensor kuj tseem cuam tshuam nrog cov qauv vaj huam sib luag:
- Dual Conversion Gain (DCG) tso cai rau lub sensor hloov ntawm hom kev rhiab heev thiab hom dynamic range siab, nyob ntawm seb lub teeb pom kev zoo li cas.
- Kev siv ntau yam HDR xav tau kev nyeem ntawv sai thiab kev tswj lub sijhawm kom meej.
- Lub kaw lus kaw thoob ntiaj teb (txawm hais tias muaj ntau dua hauv cov koob yees duab kev lag luam) yog ib qho tseem ceeb uas yuav tsum kov yeej lub kaw lus dov, tab sis nws nyuaj dua rau kev siv hauv cov xov tooj ntse vim tias nws xav tau lub capacitor cia hluav taws xob ib pixel lossis tsim qauv ntxiv uas ntxiv thaj chaw thiab qhov nyuaj.
Tag nrho cov yam ntxwv no cuam tshuam rau qhov kev teeb tsa transistor, tus lej ntawm cov txheej hlau, kev siv hluav taws xob, thiab cua sov - cov yam tseem ceeb hauv cov khoom siv nyias nyias uas muaj lub roj teeb tsawg.
9. Kev kuaj, kev kho kom raug, thiab kev koom ua ke ntawm cov module
Thaum cov wafer ua tiav lawm, cov kauj ruam tseem ceeb tom ntej yog:
- Kev kuaj qib Wafer los xyuas cov pixels tuag, suab nrov, kev sib xws, thiab cov yam ntxwv hluav taws xob.
- Txiav ua tej daim me me (txiav cov wafer ua tej daim me me), tom qab ntawd ntim khoom uas tiv thaiv cov chip thiab muab kev sib txuas.
– Kev kho kom raug: suav nrog kev kho cov duab qhia suab nrov, duab ntxoov ntxoo, qhov sib npaug dawb, thiab cov yam ntxwv ntawm lub lens. Muaj ntau yam ntawm kev kho kom raug thaum lub koob yees duab module raug sib dhos thiab sim.
- Kev koom ua ke ntawm module: lub sensor tau txuas nrog lub lens, OIS (optical image stabilization) yog tias muaj, thiab lwm yam khoom txhawb nqa. Kev sib dhos ntawm lub tshuab (tilt, focus distance) cuam tshuam loj heev rau qhov ntse.
Ntawm cov xov tooj ntse, cov koob yees duab modules yuav tsum ua tau raws li qhov kev kam rau siab thaum tseem pheej yig thiab tsim tau ntau.
10. Cov kev taw qhia yav tom ntej: ntau txheej thiab kev suav lej ze rau lub sensor
Yav tom ntej, thev naus laus zis tsim cov sensor ntawm lub xov tooj ntse yuav txav mus rau:
- Kev sib dhos ua ke ntau dua nrog kev sib txuas du thiab cov kab nruj dua.
- On-sensor AI/compute rau kev txo suab nrov, kev tshawb pom qhov chaw, lossis HDR tam sim ntawd nrog qhov latency tsawg kawg nkaus.
- Cov pixels ntse dua nrog lub architecture uas txo cov suab nrov thiab nce dynamic range yam tsis tsuas yog nce megapixels.
- Cov ntaub ntawv tshiab thiab cov qauv uas ua rau kom lub teeb nqus tau zoo dua thiab txo qhov crosstalk hauv cov pixels me me.
Txawm tias kev thaij duab hauv computer los ua tus thawj coj ntau zuj zus los xij, qhov zoo ntawm cov ntaub ntawv raw sensor tseem yog qhov tseem ceeb. Yog li ntawd, kev tsim kho tshiab - los ntawm BSI, DTI, mus rau stacked CMOS - yuav txuas ntxiv mus ua qhov tseem ceeb.
Xaus
Kev tsim cov thev naus laus zis ntawm lub koob yees duab smartphone ua ke nrog kev ua haujlwm semiconductor precision thiab micrometer-scale optical engineering. Txij li wafer lithography thiab doping, mus rau thinning rau BSI, chip stacking rau stacked sensors, mus rau microlens thiab CFA fabrication, txhua txoj kev yog tsim los pab cov sensors me me kom ntes tau lub teeb tau zoo, sai, thiab raug. Qhov tshwm sim yog cov koob yees duab smartphone txhim khu kev qha hauv ntau yam xwm txheej, thaum tab tom paving txoj hauv kev rau cov yam ntxwv tshiab xws li real-time HDR, super-fast autofocus, thiab cov yeeb yaj kiab zoo hauv cov khoom siv uas tseem me me.
Yog tias koj xav tau, kuv tuaj yeem ntxiv: (1) ib daim duab qhia txog cov txheej txheem tsim khoom hauv daim ntawv ntawm cov kauj ruam-rau-kauj ruam, (2) ib tshooj tshwj xeeb sib piv BSI vs FSI vs stacked, lossis (3) daim ntawv teev cov lus (cov lus piav qhia) kom yooj yim dua rau cov neeg nyeem ntawv.
