Nā Kumu Kumu o ka Fisika Semiconductor
ʻO ke kino semiconductor kahi lālā o ke kino e aʻo ana i ke ʻano a me nā ʻano o nā mea semiconductor. He mea koʻikoʻi kēia mea i ka ʻenehana hou, ʻoiai ʻo nā semiconductors nā mea nui i hoʻohana ʻia i ke kūkulu ʻana i nā mea uila e like me nā transistors, diodes, a me nā kaapuni i hoʻohui ʻia (ICs). Ma kēia ʻatikala, e uhi mākou i nā kumu o ke kino semiconductor, me ke ʻano atomika, ke kumumanaʻo band, ka doping, a me nā noi kūpono.
1. ʻAno ʻAtomika o nā Semiconductors
ʻO nā semiconductors he mau mea me nā waiwai conductivity uila e hāʻule ana ma waena o nā conductors (e like me ke keleawe) a me nā insulators (e like me ke aniani). ʻO nā mea semiconductor i hoʻohana pinepine ʻia ʻo silicon (Si) a me germanium (Ge). Loaʻa i nā mea ʻelua nā ʻano crystalline maʻamau kahi i hoʻopaʻa ʻia ai ko lākou mau ʻātoma kekahi i kekahi ma ke ʻano kūlike.
Hoʻopilikia nui ke ʻano atomika o kahi semiconductor i nā waiwai uila o ka mea. ʻO nā ʻātoma Silicon, no ka laʻana, he ʻehā mau electrons valence e hiki ke hana i nā pilina covalent me nā ʻātoma silicon ʻē aʻe i loko o kahi ʻano kristal tetrahedral. Hoʻopaʻa ʻia kēlā me kēia ʻātoma silicon i loko o ke kristal i ʻehā mau ʻātoma e pili ana, e hana ana i kahi pūnaewele ʻekolu-dimensional paʻa.
2. Kumumanaʻo o ka Hui Pūʻulu
I mea e maopopo ai pehea e hana ai nā semiconductors, pono mākou e hoʻomaopopo i ke kumumanaʻo band, kahi e wehewehe ana i ka hoʻolaha ʻana o ka ikehu electron i loko o kahi mea. I ke kumumanaʻo band, ua hōʻike ʻia ka ikehu o nā electrons i loko o kahi mea e ʻelua ʻano o nā kāʻei ikehu: ka valence band a me ka conduction band.
– Valence Band: ʻO kēia ka pūʻulu ikehu i noho ʻia e nā electrons ma lalo o nā kūlana maʻamau. Hoʻopaʻa paʻa ʻia nā electrons ma ka valence band i ka ʻātoma a ʻaʻole hiki ke neʻe manuahi.
– Kaʻahele Hoʻoili: ʻO kēia ka ʻaʻahele ikehu ma luna o ka ʻaʻahele valence hiki ke noho ʻia e nā electrons me ka ikehu lawa. Loaʻa i nā electrons i loko o ka ʻaʻahele hoʻoili ke kūʻokoʻa o ka neʻe ʻana, e ʻae ana iā lākou e pāʻani i kahi kuleana i ka hoʻoili uila.
Ma waena o ke kāʻei valence a me ke kāʻei conduction aia kahi hakahaka ikehu i kapa ʻia ʻo Energy Gap a i ʻole Band Gap. I loko o nā alakaʻi, he liʻiliʻi loa kēia hakahaka band a ʻaʻole paha, e ʻae ana i nā electrons e neʻe maʻalahi mai ke kāʻei valence a i ke kāʻei conduction. I loko o nā insulators, he nui loa kēia hakahaka band, no laila he kakaikahi wale nō nā electrons e hiki i ke kāʻei conduction.
Ma ka ʻaoʻao ʻē aʻe, he wahi hakahaka waena ko nā semiconductors. Hiki i nā electrons ke neʻe mai ka valence band a i ka conduction band inā hāʻawi ʻia ka ikehu lawa, no ka laʻana ma o ka wela a i ʻole nā photons (mālamalama).
3. Hoʻohana ʻia ka lāʻau lapaʻau
ʻO kekahi ala e kāohi ai i ka conductivity o kahi semiconductor ma o ka doping ʻana. ʻO ka doping ke kaʻina hana o ka hoʻohui ʻana i nā haumia a i ʻole nā ʻātoma o nā mea ʻē aʻe i kahi semiconductor maʻemaʻe e hoʻololi i kona mau waiwai conductivity.
– ʻO ka doping ʻano-N: Pili i ka hoʻohui ʻana i kahi mea i loaʻa nā electrons valence ʻoi aku ma mua o ka semiconductor kumu. No ka laʻana, inā mākou e hoʻohui i ka phosphorus (P) i ka silicon, hāʻawi mākou i nā electrons hou e hiki ke hoʻonui i ka conductivity uila. Ua kapa ʻia kēia he semiconductor ʻano-n ma muli o nā electrons maikaʻi ʻole keu.
– ʻO ka doping ʻano-P: Pili i ka hoʻohui ʻana o kahi mea nona nā electrons valence liʻiliʻi ma mua o ka semiconductor kumu. No ka laʻana, inā mākou e hoʻohui i ka boron (B) i ka silicon, hana mākou i nā "lua" i loko o ke ʻano kristal e hana ma ke ʻano he mau mea lawe uku maikaʻi. Ua kapa ʻia kēia he semiconductor ʻano-p ma muli o ke alo o nā lua maikaʻi.
4. Ka mea lawe ukana a me ka neʻe ʻana
I loko o nā semiconductors, ʻo nā ʻano nui ʻelua o nā mea lawe ukana he mau electrons a me nā lua. He mau ʻāpana i hoʻopiʻi maikaʻi ʻole ʻia nā electrons, ʻoiai ʻo nā lua ke kumumanaʻo o nā hakahaka electron e hiki ke neʻe i loko o ke ʻano kristal.
– Ka Neʻe ʻana o ka Electron: Ke ana i ka wikiwiki o ka neʻe ʻana o nā electrons ma o kahi semiconductor ke hoʻopili ʻia ke au uila.
– Ka Neʻe ʻana o ka Hole: Ke ana i ka wikiwiki o ka neʻe ʻana o nā lua ma o kahi semiconductor.
ʻO ka neʻe ʻana o ka mea lawe ukana e pili ana i kekahi mau kumu, me ka mahana a me ke ʻano o ka dopant i hoʻohana ʻia. I nā mahana kiʻekiʻe, hiki i ka ikehu wela ke hoʻonui i ka neʻe ʻana o nā mea lawe ukana akā hoʻonui pū i ka pilina ma waena o nā mea lawe ukana a me nā ʻātoma i loko o ke kristal, hiki ke kāohi i ko lākou neʻe ʻana.
5. hui pn (Hui pn)
ʻO ka hui ʻana ma waena o nā ʻano semiconductors ʻelua, ʻo ke ʻano-p a me ke ʻano-n, he ʻano koʻikoʻi ia i nā mea semiconductor e like me nā diodes, transistors, a me nā photovoltaics. Loaʻa i ka hui p-n ka waiwai kū hoʻokahi o ka ʻae ʻana i ke au uila e kahe i hoʻokahi ʻaoʻao akā ʻaʻole ma ke ʻaoʻao ʻē aʻe, e lilo ia i mea nui i ka hoʻoponopono ʻana i ke au uila.
– Diode: He ʻāpana e ʻae ai i ke au e kahe i hoʻokahi wale nō ʻaoʻao. Ke hoʻopili ʻia kahi voltage i mua i kahi diode (kahi voltage e hoʻolilo i ka ʻaoʻao-p i ʻoi aku ka maikaʻi ma mua o ka ʻaoʻao-n), hiki ke kahe ke au. I ka ʻaoʻao ʻē aʻe, ke hoʻopili ʻia kahi voltage hoʻohuli i kahi diode, ʻaʻohe kahe o ke au.
– Transistor: He mea hana e hoʻonui a hoʻololi paha i ke au. I loko o kahi transistor, aia ʻelua ʻano o nā hui p-n i hoʻonohonoho ʻia e kāohi i ke kahe o nā electrons.
6. Nā noi Semiconductor
He mea nui nā semiconductors i nā mea uila hou. ʻO kekahi o kā lākou mau noi koʻikoʻi:
– Nā Kaapuni Hoʻohui ʻia (IC): Kapa ʻia hoʻi he microchips, ʻo IC he mau hōʻiliʻili o nā transistors he nui a me nā ʻāpana uila ʻē aʻe i hui pū ʻia ma kahi chip hoʻokahi. ʻO lākou ke kumu o nā kamepiula, nā kelepona akamai, a me nā mea uila like ʻole.
– Nā Diode Hoʻopuka Mālamalama (LED): Hoʻohana nā LED i nā mea semiconductor e hana i ka mālamalama ke hoʻopili ʻia kahi au uila. He mālama pono loa lākou i ka ikehu a hoʻohana ʻia i nā ʻano hana like ʻole, mai ka kukui home a i nā pale hōʻike.
– Photovoltaic (PV): Hoʻohana nā pūnaewele PV, a i ʻole nā kelepona solar, i nā semiconductors e hoʻololi pololei i ka ikehu māmā i ikehu uila. Ke paʻi nā photons mai ka lā i ka semiconductor, hāʻawi lākou i ka ikehu lawa no nā electrons e lele ma waena o ka band gap, e hana ana i kahi au uila.
7. Nā Pilikia a me nā Noiʻi e Hiki Mai Ana
Ke hoʻomau nei ka noiʻi e ʻimi i nā mea semiconductor hou i ʻoi aku ka maikaʻi, emi ke kumukūʻai, a loaʻa nā waiwai i makemake ʻia no nā noi kikoʻī. No ka laʻana, hāʻawi nā semiconductors i hoʻokumu ʻia ma ka gallium nitride (GaN) a i ʻole graphene i ka hiki ke loaʻa nā mea uila wikiwiki a ʻoi aku ka maikaʻi i ka wā e hiki mai ana.
ʻO nā pilikia ʻē aʻe e pili ana i ka mālama ʻana i ke kūpaʻa a me ka hana o nā mea semiconductor ma nā mahana kiʻekiʻe a me nā kūlana kaiapuni koʻikoʻi, a me ka lanakila ʻana i nā palena o nā mea laha ʻole i hoʻohana ʻia i ka doping.
Ka hopena
He kahua koʻikoʻi a paʻakikī hoʻi ka physics semiconductor, e pili ana i ka hapa nui o ka ʻenehana uila hou. Ma ka hoʻomaopopo ʻana i nā manaʻo kumu e like me ke ʻano atomika, ke kumumanaʻo band, ka doping, a me nā noi hana, hiki iā mākou ke mahalo a hoʻomohala i nā ʻenehana e hiki mai ana e hilinaʻi nei i nā semiconductors. ʻO ka hoʻomau ʻana o ka noiʻi a me ka hana hou i nā mea semiconductor e hoʻomau i ka hoʻokuke ʻana i nā palena o ka mea hiki ke hana i nā mea uila.
