ʻO ke kumumanaʻo mālamalama o ka LED

A pauke kukui hana hiki ke hoʻouka hou ʻia, kukui hoʻomoana lawe limaa mekukui poʻo hana he nuie hoʻohana i ke ʻano kukui LED. No ka hoʻomaopopo ʻana i ke kumumanaʻo o ka diode led, e hoʻomaopopo mua i ka ʻike kumu o nā semiconductors. Aia nā waiwai alakaʻi o nā mea semiconductor ma waena o nā alakaʻi a me nā insulators. ʻO kona mau hiʻohiʻona kūikawā: ke hoʻoulu ʻia ka semiconductor e nā kūlana mālamalama a me ka wela o waho, e loli nui kona hiki ke alakaʻi; ʻO ka hoʻohui ʻana i nā mea haumia liʻiliʻi i kahi semiconductor maʻemaʻe e hoʻonui nui i kona hiki ke alakaʻi i ka uila. ʻO Silicon (Si) a me germanium (Ge) nā semiconductors i hoʻohana nui ʻia i nā mea uila hou, a ʻehā ko lākou mau electrons waho. Ke hana nā ʻātoma silicon a germanium paha i kristal, e launa pū nā ʻātoma e pili ana me kekahi i kekahi, i kaʻana like ʻia nā electrons waho e nā ʻātoma ʻelua, kahi e hana ai i ke ʻano pilina covalent i loko o ke kristal, he ʻano molekala me ka liʻiliʻi o ka hiki ke kāohi. Ma ka mahana o ka lumi (300K), e hana ka hoʻonāukiuki wela i kekahi mau electrons waho e loaʻa ka ikehu e uhaki ai mai ka pilina covalent a lilo i mau electrons manuahi, ua kapa ʻia kēia kaʻina hana intrinsic excitation. Ma hope o ka wehe ʻia ʻana o ka electron e lilo i electron manuahi, waiho ʻia kahi hakahaka i loko o ka pilina covalent. Ua kapa ʻia kēia hakahaka he lua. ʻO ke ʻano o ka lua he hiʻohiʻona nui ia e hoʻokaʻawale i kahi semiconductor mai kahi alakaʻi.

Ke hoʻohui ʻia kahi liʻiliʻi o ka haumia pentavalent e like me ka phosphorus i ka semiconductor intrinsic, e loaʻa iā ia kahi electron keu ma hope o ka hoʻokumu ʻana i kahi pilina covalent me nā ʻātoma semiconductor ʻē aʻe. Pono wale kēia electron keu i ka ikehu liʻiliʻi loa e hoʻopau ai i ka pilina a lilo i electron manuahi. Ua kapa ʻia kēia ʻano semiconductor haumia he semiconductor uila (N-type semiconductor). Eia naʻe, ʻo ka hoʻohui ʻana i kahi liʻiliʻi o nā haumia elemental trivalent (e like me boron, etc.) i ka semiconductor intrinsic, no ka mea, he ʻekolu wale nō electrons ma ka papa waho, ma hope o ka hoʻokumu ʻana i kahi pilina covalent me nā ʻātoma semiconductor a puni, e hana ia i kahi hakahaka i loko o ke kristal. Ua kapa ʻia kēia ʻano semiconductor haumia he semiconductor lua (P-type semiconductor). Ke hui pū ʻia nā semiconductors N-type a me P-type, aia kahi ʻokoʻa i ka nui o nā electrons manuahi a me nā lua ma ko lākou hui ʻana. Hoʻolaha ʻia nā electrons a me nā lua i ka nui haʻahaʻa, e waiho ana i nā ion i hoʻopiʻi ʻia akā paʻa ʻole e hoʻopau i ka neutrality uila mua o nā ʻāpana N-type a me P-type. ʻO kēia mau ʻāpana i hoʻopiʻi ʻia i neʻe mau ʻia ua kapa pinepine ʻia he mau uku lewa, a ua hoʻopili ʻia lākou ma kahi kokoke i ka pilina o nā ʻāpana N a me P e hana i kahi ʻāpana lahilahi loa o ka uku lewa, i ʻike ʻia ʻo ka PN junction.

Ke hoʻopili ʻia kahi voltage bias forward i nā wēlau ʻelua o ka PN junction (voltage maikaʻi i kekahi ʻaoʻao o ke ʻano P), neʻe nā lua a me nā electrons manuahi a puni kekahi i kekahi, e hana ana i kahi kahua uila kūloko. A laila hui hou nā lua i hoʻokomo hou ʻia me nā electrons manuahi, i kekahi manawa e hoʻokuʻu ana i ka ikehu keu ma ke ʻano o nā photons, ʻo ia ke kukui a mākou e ʻike ai i hoʻopuka ʻia e nā leds. He haiki iki kēlā ʻano spectrum, a no ka mea he ʻokoʻa ka band gap o kēlā me kēia mea, ʻokoʻa nā nalu o nā photons i hoʻopuka ʻia, no laila ua hoʻoholo ʻia nā kala o nā leds e nā mea kumu i hoʻohana ʻia.