Chikamu Chechipiri: Hunhu hwechinoongorora maavalanche (APD photodetector)

Nheyo huru nemamiriro ezvinhu aripo iye zvinochinhu chinoona mafashamo emvura (Chinoongorora mufananidzo cheAPDChikamu Chechipiri

2.2 Chip yakagadzirwa neAPD
Chimiro chechip chinonzwisisika ndicho vimbiso huru yezvishandiso zvinoshanda zvakanaka. Dhizaini yechimiro cheAPD inonyanya kufunga nezvenguva yeRC isingachinji, kubatwa kwemaburi panguva yekubatana, nguva yekufambisa yekutakura kuburikidza nenzvimbo yekupera simba nezvimwewo. Kuvandudzwa kwechimiro chayo kwakapfupikiswa pazasi:

(1) Chimiro chepakutanga
Chimiro cheAPD chakareruka chakavakirwa paPIN photodiode, dunhu reP nenzvimbo yeN zvakanyikwa zvakanyanya, uye dunhu reN-type kana P-type rinodzorwa kaviri rinounzwa munzvimbo iri pedyo yeP kana N kuti rigadzire maerekitironi echipiri nemaburi maviri, kuitira kuti pave nekuwedzera kweprimary photocurrent. Kune zvinhu zveInP series, nekuti hole impact ionization coefficient yakakura kupfuura electron impact ionization coefficient, gain region yeN-type doping inowanzoiswa munzvimbo yeP. Mumamiriro ezvinhu akanaka, maburi chete ndiwo anopinzwa munzvimbo yegain, saka chimiro ichi chinonzi hole-injected structure.

(2) Kunwa uye kuwana zvinoonekwa
Nekuda kwehunhu hweInP hwakafara (wide band gap) (InP i1.35eV uye InGaAs i0.75eV), InP inowanzo shandiswa sezvinhu zvegain zone uye InGaAs sezvinhu zveabsorption zone.

(3) Maumbirwo ekunyudzwa, kukwira uye kuwanikwa (SAGM) anotsanangurwa zvichiteerana
Parizvino, michina yakawanda yeAPD yekutengeserana inoshandisa zvinhu zveInP/InGaAs, InGaAs sechikamu chekunyudza, InP pasi pesimba remagetsi rakawanda (>5x105V/cm) pasina kuputsika, inogona kushandiswa senzvimbo yekuwana gain. Pachinhu ichi, dhizaini yeAPD iyi ndeyekuti maitiro ekudonha kwevhu anoumbwa muN-type InP nekusangana kwemaburi. Tichifunga nezvemusiyano mukuru uripo pakati peInP neInGaAs, musiyano wesimba weinenge 0.4eV mubhandi revalence unoita kuti maburi anogadzirwa muInGaAs absorption layer avharidzike pamucheto weheterojunction asati asvika paInP multiplier layer uye kumhanya kunoderedzwa zvakanyanya, zvichikonzera nguva refu yekupindura uye bandwidth yakamanikana yeAPD iyi. Dambudziko iri rinogona kugadziriswa nekuwedzera InGaAsP transition layer pakati pezvinhu zviviri izvi.

(4) Maumbirwo ekunyudzwa, kukwira, kuchaja uye kuwana (SAGCM) anotsanangurwa zvichiteerana
Kuti tigadzirise zvakanyanya kugoverwa kwemagetsi kwechikamu chekunyudza uye chikamu chekukwira, chikamu chekuchaja chinoiswa mukugadzirwa kwemudziyo, izvo zvinovandudza zvikuru kumhanya kwemudziyo uye kupindura kwawo.

(5) Kugadziriswa kweSAGCM (Resonator) kwakasimbiswa (RCE)
Mukugadzirwa kwakanakisa kwema detector echinyakare, tinofanira kutarisana nechokwadi chekuti ukobvu hwe absorption layer chinhu chinopesana nekumhanya kwemudziyo uye kushanda zvakanaka kwe quantum. Ukobvu hwakatetepa hwe absorption layer hunogona kuderedza nguva yekufambisa ye carrier, saka bandwidth yakakura inogona kuwanikwa. Zvisinei, panguva imwe chete, kuti uwane kushanda zvakanaka kwe quantum, absorption layer inofanirwa kuve nehukobvu hwakakwana. Mhinduro yedambudziko iri inogona kuve chimiro che resonant cavity (RCE), ndiko kuti, distributed Bragg Reflector (DBR) yakagadzirwa pasi nepamusoro pemudziyo. DBR mirror ine mhando mbiri dzezvinhu zvine low refractive index uye high refractive index muchimiro, uye zviviri izvi zvinokura zvichichinjana, uye ukobvu hwe layer yega yega hunosangana ne incident light wavelength 1/4 mu semiconductor. Chimiro che resonator che detector chinogona kusangana nezvinodiwa zvekumhanya, ukobvu hwe absorption layer hunogona kuitwa hutete kwazvo, uye kushanda zvakanaka kwe quantum kwe electron kunowedzerwa mushure mekuratidzira kwakawanda.

(6) Chimiro cheguide yewave chakabatana nemucheto (WG-APD)
Imwe mhinduro yekugadzirisa kupesana kwemhedzisiro dzakasiyana dzekukora kwechikamu chekunyudzwa pakumhanya kwemudziyo uye kushanda zvakanaka kwe quantum ndeyekuisa chimiro che waveguide chakabatana nemucheto. Chimiro ichi chinopinda muchiedza kubva parutivi, nekuti chikamu chekunyudzwa chakareba kwazvo, zviri nyore kuwana kushanda zvakanaka kwe quantum, uye panguva imwe chete, chikamu chekunyudzwa chinogona kuitwa chakatetepa, zvichideredza nguva yekufambisa yemutakuri. Naizvozvo, chimiro ichi chinogadzirisa kutsamira kwakasiyana kwe bandwidth uye kushanda zvakanaka pakukora kwechikamu chekunyudzwa, uye chinotarisirwa kuwana APD yekukurumidza uye kushanda zvakanaka kwe quantum. Maitiro eWG-APD ari nyore pane eRCE APD, ayo anobvisa maitiro akaoma ekugadzirira eDBR mirror. Nokudaro, zvinogoneka zviri nyore mumunda wekushanda uye zvakakodzera kubatana kwe common plane optical.

3. Mhedziso
Kukura kwemafashamo emvuramudziyo wekuona fotozvinhu nemidziyo zvinoongororwa. Mwero we ionization ye electron ne hole collision yezvinhu zveInP wakafanana neweInAlAs, izvo zvinotungamira kune maitiro maviri e carrier symbions, izvo zvinoita kuti nguva yekuvaka avalanche irebe uye ruzha rwakawedzera. Zvichienzaniswa nezvinhu zveInAlAs zvakachena, InGaAs (P) /InAlAs uye In (Al) GaAs/InAlAs quantum well structures dzine chiyero chakawedzerwa che collision ionization coefficients, saka mashandiro eruzha anogona kuchinjwa zvakanyanya. Panyaya yechimiro, resonator enhanced (RCE) SAGCM structure uye edge-coupled waveguide structure (WG-APD) zvakagadzirwa kuitira kugadzirisa kupesana kwemhedzisiro dzakasiyana dzekunyudzwa kwe layer thickness pakumhanya kwemudziyo uye kushanda kwe quantum. Nekuda kwekuoma kwemaitiro acho, kushandiswa kwakazara kwezvivakwa izvi zviviri kunofanirwa kuongororwa zvakanyanya.