Nā mea ʻike kiʻi a me nā nalu ʻokiʻoki

Nā mea nānā kiʻia me nā nalu ʻokiʻoki

Ke nānā nei kēia ʻatikala i nā mea hana a me nā loina hana o nā photodetectors (ʻoi aku ka ʻano hana pane e pili ana i ke kumumanaʻo band), a me nā palena koʻikoʻi a me nā hiʻohiʻona noi o nā mea semiconductor like ʻole.
1. Kumumanaʻo koʻikoʻi: Hana ka photodetector ma muli o ka hopena photoelectric. Pono nā photons incident e lawe i ka ikehu lawa (ʻoi aku ka nui ma mua o ka laulā bandgap Eg o ka mea) e hoʻonāukiuki i nā electrons mai ka valence band a i ka conduction band, e hana ana i kahi hōʻailona uila hiki ke ʻike ʻia. He kūlike ʻole ka ikehu photon i ka nalu, no laila he "wavelength cut-off" (λ c) ka mea ʻike - ʻo ia ka nalu kiʻekiʻe loa e hiki ke pane, ma ʻō aku o ia mea ʻaʻole hiki ke pane maikaʻi. Hiki ke kuhi ʻia ka nalu cutoff me ka hoʻohana ʻana i ke ʻano λ c ≈ 1240/Eg (nm), kahi i ana ʻia ai ʻo Eg ma eV.
2. Nā mea semiconductor koʻikoʻi a me ko lākou mau ʻano:
Silicon (Si): ka laulā o ka bandgap ma kahi o 1.12 eV, ka nalu ʻokiʻoki ma kahi o 1107 nm. Kūpono no ka ʻike ʻana i nā nalu pōkole e like me 850 nm, i hoʻohana pinepine ʻia no ka hoʻopili ʻana o ka fiber optic multimode pōkole (e like me nā kikowaena ʻikepili).
ʻO Gallium arsenide (GaAs): ka laulā o ka bandgap o 1.42 eV, ka nalu ʻokiʻoki ma kahi o 873 nm. Kūpono no ke kaula nalu 850 nm, hiki ke hoʻohui ʻia me nā kumu kukui VCSEL o ka mea like ma kahi chip hoʻokahi.
ʻO Indium gallium arsenide (InGaAs): Hiki ke hoʻololi ʻia ka laulā o ka bandgap ma waena o 0.36 ~ 1.42 eV, a ʻo ka nalu ʻoki e uhi ana i 873 ~ 3542 nm. ʻO ia ka mea ʻike nui no nā puka makani kamaʻilio fiber 1310 nm a me 1550 nm, akā koi ʻia kahi substrate InP a he paʻakikī ke hoʻohui me nā kaapuni e pili ana i ka silicon.
ʻO Germanium (Ge): me ka laulā bandgap o kahi o 0.66 eV a me kahi nalu cutoff o kahi o 1879 nm. Hiki iā ia ke uhi i 1550 nm a i 1625 nm (L-band) a kūpono me nā substrates silicon, e lilo ia i hopena kūpono no ka hoʻonui ʻana i ka pane i nā kaula lōʻihi.
ʻO ka hui ʻana o Silicon germanium (e like me Si0.5Ge0.5): ka laulā o ka bandgap ma kahi o 0.96 eV, ka nalu ʻokiʻoki ma kahi o 1292 nm. Ma ka hoʻohui ʻana i ka germanium i loko o ka silicon, hiki ke hoʻonui ʻia ka nalu pane i nā kaula lōʻihi ma ka substrate silicon.
3. Hoʻohui ʻana i ke ʻano noi:
850 nm ka huila:Nā mea ʻike kiʻi Silicona i ʻole hiki ke hoʻohana ʻia nā mea ʻike kiʻi GaAs.
1310/1550 nm ka hui:Nā mea ʻike kiʻi InGaAshoʻohana nui ʻia. Hiki i nā photodetectors germanium maʻemaʻe a i ʻole silicon germanium alloy ke uhi i kēia pae a loaʻa nā pono kūpono i ka hoʻohui ʻana ma muli o ka silicon.

Ma keʻano holoʻokoʻa, ma o nā manaʻo koʻikoʻi o ke kumumanaʻo band a me ka cutoff wavelength, ua loiloi ʻia nā ʻano noi a me ka laulā uhi wavelength o nā mea semiconductor like ʻole i nā photodetectors, a ua kuhikuhi ʻia ka pilina pili ma waena o ke koho ʻana i nā mea, ka puka makani wavelength kamaʻilio fiber optic, a me ke kumukūʻai o ke kaʻina hana hoʻohui.