Ama-Photodetector nama-wavelength anqunyelwe

Ama-Photodetectorskanye nama-wavelength anqunyelwe

Lesi sihloko sigxile ezintweni zokwakha kanye nezimiso zokusebenza zama-photodetector (ikakhulukazi indlela yokusabela esekelwe kumbono webhendi), kanye namapharamitha ayisihluthulelo kanye nezimo zokusetshenziswa kwezinto ezahlukene ze-semiconductor.
1. Isimiso esiyinhloko: I-photodetector isebenza ngokusekelwe kumphumela we-photoelectric. Ama-photon ahilelekile adinga ukuthwala amandla anele (angaphezu kobubanzi be-bandgap Eg yezinto ezibonakalayo) ukuze avuse ama-electron kusuka ku-valence band aye ku-conduction band, okwenza isignali kagesi etholakala. Amandla e-photon alingana ngokuphambene nobude be-wavelength, ngakho-ke i-detector ine-"cut-off wavelength" (λ c) - ubude be-wavelength obuphezulu obungaphendula, ngaphezu kwalokho obungenakukwazi ukuphendula ngempumelelo. Ububanzi be-wavelength obunqamukile bungalinganiswa kusetshenziswa ifomula λ c ≈ 1240/Eg (nm), lapho i-Eg ilinganiswa khona ku-eV.
2. Izinto ezibalulekile ze-semiconductor kanye nezici zazo:
I-Silicon (Si): ububanzi be-bandgap obungaba ngu-1.12 eV, ubude be-cutoff obungaba ngu-1107 nm. Ifaneleka ukuthola ubude be-wavelength obufushane njengo-850 nm, evame ukusetshenziswa ekuxhumekeni kwe-fiber optic ye-multimode emfushane (njengezikhungo zedatha).
I-Gallium arsenide (GaAs): ububanzi be-bandgap obungu-1.42 eV, ubude be-cutoff obungaba ngu-873 nm. Ifanelekela ibhendi ye-wavelength engu-850 nm, ingahlanganiswa nemithombo yokukhanya ye-VCSEL yezinto ezifanayo ku-chip eyodwa.
I-Indium gallium arsenide (InGaAs): Ububanzi be-bandgap bungalungiswa phakathi kuka-0.36~1.42 eV, kanti ubude be-cutoff wavelength bumboza u-873~3542 nm. Yinto esetshenziswa kakhulu ukuthola amafasitela okuxhumana ngefayibha angu-1310 nm kanye no-1550 nm, kodwa idinga i-substrate ye-InP futhi iyinkimbinkimbi ukuyihlanganisa namasekethe asekelwe ku-silicon.
I-Germanium (Ge): enobubanzi be-bandgap obungaba ngu-0.66 eV kanye nobude be-cutoff obungaba ngu-1879 nm. Ingamboza kusukela ku-1550 nm kuya ku-1625 nm (i-L-band) futhi iyahambisana ne-silicon substrates, okwenza kube yisisombululo esisebenzayo sokwandisa impendulo kuma-band amade.
I-silicon germanium alloy (njenge-Si0.5Ge0.5): ububanzi be-bandgap obungaba ngu-0.96 eV, ubude be-cutoff obungaba ngu-1292 nm. Ngokufaka i-germanium ku-silicon, ubude be-response bungandiswa kuma-band amade ku-substrate ye-silicon.
3. Ukuhlanganiswa kwesimo sesicelo:
Ibhendi engu-850 nm:Izitholi zesithombe ze-siliconnoma ama-photodetector e-GaAs angasetshenziswa.
Ibhendi engu-1310/1550 nm:Izitholi zezithombe ze-InGaAszisetshenziswa kakhulu. Ama-photodetector e-germanium ahlanzekile noma i-silicon germanium alloy angahlanganisa lolu hlu futhi abe nezinzuzo ezingaba khona ekuhlanganisweni okusekelwe ku-silicon.

Sekukonke, ngemiqondo eyinhloko yethiyori yebhendi kanye nobude be-cutoff, izici zohlelo lokusebenza kanye nobubanzi bokumbozwa kobude be-wavelength bezinto ezahlukene ze-semiconductor kuma-photodetectors kubuyekezwe ngokuhlelekile, futhi ubudlelwano obuseduze phakathi kokukhethwa kwezinto, ifasitela lobude be-wavelength yokuxhumana kwe-fiber optic, kanye nezindleko zenqubo yokuhlanganisa buye bavezwa.