Dab tsi yog Cov Ntsiab Cai thiab Kev Siv Tus PIN Diodes? (Part 1)

Tus PIN Photodiodeyog ib qho khoom siv semiconductor uas muaj tus PIN hlws ris uas hloov cov teeb liab kho qhov muag rau hauv lub teeb liab hluav taws xob uas hloov pauv raws li lub teeb hloov. Nws yog tsom rau qhov tsis muaj peev xwm ntawm PD dav dav, cov qauv txhim kho, thiab qhov rhiab heev yog siab dua li ntawm PN junction photodiode, thiab nws muaj cov yam ntxwv ntawm kev coj ua ib leeg.

1. Txoj cai thiab qauv ntawm tus PIN diode

Cov diode dav dav yog tsim los ntawm N-hom impurity doped semiconductor cov khoom thiab P-hom impurity doped semiconductor cov khoom ncaj qha los tsim PN kev sib tshuam. Tus PIN diode yog ntxiv ib txheej nyias ntawm cov khoom siv qis-doping Intrinsic semiconductor ntawm P-type semiconductor khoom thiab N-hom semiconductor khoom.

Daim duab kos duab ntawm tus PIN diode yog pom nyob rau hauv daim duab 1 vim hais tias lub intrinsic semiconductor zoo ib yam li qhov nruab nrab, qhov no yog sib npaug rau qhov kev ncua deb ntawm ob lub electrodes ntawm PN hlws ris capacitor, thiaj li hais tias lub hlws ris capacitor ua me me. Qhov thib ob, qhov dav ntawm cov txheej txheem depletion hauv P-hom semiconductor thiab N-hom semiconductor tau nthuav dav nrog qhov nce ntawm qhov rov qab voltage, thiab qhov sib txuas ntawm qhov hluav taws xob kuj tseem me me nrog qhov nce ntawm qhov rov qab tsis zoo. Vim tias muaj cov txheej txheem I, thiab thaj tsam P feem ntau nyias nyias, qhov xwm txheej photon tsuas tuaj yeem nqus tau rau hauv txheej I, thiab qhov rov qab tsis ncaj ncees feem ntau yog nyob rau hauv cheeb tsam I, tsim cov cheeb tsam hluav taws xob siab, thiab cov khoom siv photogenerated. nyob rau hauv lub cheeb tsam kuv accelerates nyob rau hauv qhov kev txiav txim ntawm lub zog hluav taws xob teb, yog li cov cab kuj lub sij hawm hloov mus tas li txo, yog li txhim kho cov zaus teb ntawm lub photodiode. Nyob rau tib lub sijhawm, kev taw qhia ntawm txheej kuv nthuav dav thaj tsam depletion thiab nthuav dav thaj chaw ua haujlwm zoo ntawm photoelectric hloov dua siab tshiab, yog li txhim kho qhov rhiab heev.

Muaj ob lub qauv ntawm tus PIN diode, uas yog, cov qauv ntawm lub dav hlau thiab cov qauv ntawm mesa, raws li qhia hauv daim duab 2. Rau Si-pin133 junction diodes, cov cab kuj concentration ntawm txheej kuv yog tsawg heev (txog 10cm kev txiav txim. ntawm qhov loj), qhov resistivity siab heev (txog k-cm qhov kev txiav txim ntawm qhov loj), thiab lub thickness W yog feem ntau tuab (nruab nrab ntawm 10 thiab 200m); Lub doping concentration ntawm P-hom thiab N-hom semiconductors ntawm ob sab ntawm I txheej feem ntau yog siab heev.

Cov txheej I ntawm ob qho tib si planar thiab mesa cov qauv tuaj yeem tsim los ntawm epitaxy thev naus laus zis, thiab cov txheej txheem doped p ntxiv tuaj yeem tau txais los ntawm thermal diffusion lossis ion implantation technology. Planar diodes tuaj yeem tsim tau yooj yim los ntawm cov txheej txheem planar. Mesa qauv diode kuj yuav tsum tau fabricated (los ntawm etching los yog grooving). Qhov zoo ntawm mesa qauv yog:

① Cov dabtsi yog khoov ntawm lub dav hlau hlws ris raug tshem tawm, thiab qhov chaw tawg hluav taws xob tau zoo dua;

②Cov ntug capacitance thiab inductance raug txo, uas yog qhov tsim nyog rau kev txhim kho kev ua haujlwm zaus.

2. PIN diode ua hauj lwm lub xeev nyob rau hauv txawv bias

① Zoo downward drift

Thaum tus PIN diode siv nrog rau pem hauv ntej voltage, ntau moles nyob rau hauv cheeb tsam P thiab N cheeb tsam yuav raug txhaj rau hauv cheeb tsam I thiab recombined nyob rau hauv cheeb tsam I. Thaum cov tshuaj tua kab mob thiab cov khoom sib xyaw ua ke sib npaug, qhov tam sim no kuv mus txog qhov sib npaug. Lub hauv paus txheej txheem muaj qhov tsis kam tiv thaiv vim qhov sib txuam ntawm ntau tus neeg nqa khoom, yog li thaum tus PIN diode nyob rau pem hauv ntej-txhawj xeeb, nws muaj cov yam ntxwv tsis zoo. Qhov ntau dua qhov kev tsis ncaj ncees rau pem hauv ntej, qhov ntau dua qhov tam sim no txhaj rau hauv I txheej, thiab cov neeg nqa khoom ntau dua hauv I txheej, ua rau nws qhov kev tiv thaiv me me. Daim duab 3 yog qhov sib npaug ntawm daim duab kos nyob rau hauv qhov kev tsis zoo, thiab nws tuaj yeem pom tau tias nws yog qhov sib npaug me me nrog tus nqi tsis kam ntawm 0.1Ω thiab 10Ω.

② Zero deviation

Thaum tsis muaj qhov hluav taws xob siv rau ntawm ob qho kawg ntawm tus PIN diode, vim tias qhov tseeb kuv txheej muaj ib qho me me ntawm P-hom impurities, ntawm IN interface, qhov nyob hauv cheeb tsam I diffuse mus rau thaj tsam N, thiab cov hluav taws xob nyob hauv. N cheeb tsam diffuse mus rau thaj tsam I, thiab tom qab ntawd tsim ib cheeb tsam chaw them nqi. Vim tias cov impurity concentration nyob rau hauv Zone I yog tsawg heev piv nrog rau hauv Zone N, feem ntau ntawm cov depletion cheeb tsam yog yuav luag nyob rau hauv Zone I. Ntawm PI interface, vim lub concentration sib txawv (lub qhov concentration nyob rau hauv lub P cheeb tsam yog ntau npaum li cas loj dua. hais tias nyob rau hauv cheeb tsam kuv), diffusion tsab ntawv tsa suab kuj yuav tshwm sim, tab sis nws cov nyhuv yog npaum li cas me dua qhov uas nyob rau hauv lub interface thiab yuav ignored. Yog li ntawd, ntawm xoom tsis ncaj ncees lawm, tus PIN diode nthuav tawm lub xeev muaj zog tiv thaiv vim tias muaj thaj tsam depletion hauv cheeb tsam I.

③ Reverse downward bias

Qhov rov qab kev tsis ncaj ncees yog zoo ib yam li xoom kev tsis ncaj ncees, tshwj tsis yog tias qhov chaw hluav taws xob built-in tau ntxiv dag zog, thiab cov txiaj ntsig yog kom nthuav dav thaj chaw them nqi ntawm IN junction, feem ntau ntawm thaj tsam I. Lub sijhawm no, tus PIN diode tuaj yeem sib npaug rau qhov kev tiv thaiv ntxiv rau lub peev xwm, qhov kev tawm tsam yog qhov seem hauv cheeb tsam tsis kam, thiab qhov capacitance yog qhov barrier capacitance ntawm cheeb tsam depletion. Daim duab 4 yog daim duab sib npaug sib npaug ntawm tus PIN diode nyob rau hauv qhov kev tsis ncaj ncees, thiab nws tuaj yeem pom tau tias qhov kev tawm tsam yog nyob nruab nrab ntawm 1Ω thiab 100Ω, thiab qhov muaj peev xwm ntawm 0.1pF thiab 10 PF. Thaum qhov rov qab kev tsis ncaj ncees loj dhau lawm, kom qhov chaw depletion puv tag nrho I tsam, kuv qhov kev nkag mus yuav tshwm sim, thiab tus PIN tube yuav tsis ua haujlwm ib txwm.

Cov ntaub ntawv tiv tauj:

Yog tias koj muaj lus nug, thov hu rau peb. Txawm peb cov neeg muas zaub nyob qhov twg thiab peb cov kev xav tau yog dab tsi, peb yuav ua raws li peb lub hom phiaj los muab peb cov neeg siv khoom zoo, tus nqi qis, thiab kev pabcuam zoo tshaj plaws.