バンドギャップが小さい極めて薄い層をバンドギャップが大きい層で挟み込ん

バンドギャップが小さい極めて薄い層をバンドギャップが大きい層で挟み込んだ構造のこと。バンドギャップが小さい層のポテンシャルは周囲（バンドギャップが大きい層）よりも低く，ポテンシャルの井戸（量子井戸）ができている。LEDや半導体レーザなどにおいて，量子井戸構造を光を放射する活性層に用いている。量子井戸を複数重ねた構造は多重量子井戸（MQW：multi quantum well）と呼ぶ。

青色LEDなどは，量子井戸構造といったGaN系結晶層の層構造を改良することで発展してきた。GaN系LEDはMIS（metal-insulatorsemiconductor）構造，pn 接合型ダブルヘテロ構造，単一量子井戸を採用したダブルヘテロ構造，多重量子井戸を採用したダブルヘテロ構造となるにつれ，輝度や色純度が高まる。MIS構造の青色LEDは，p型GaN膜が作製できない時期に，開発・製品化されていた。光度が数百mcdしか得られないという欠点があった。その後，p型GaN膜を作製できるようになったため，pn接合型ダブルヘテロ構造を採用した青色LEDが実現可能になった。MIS構造に比べて約10倍の発光輝度である1cdを達成できた。多重量子井戸構造で置き換えると発光光度がさらに増し，さらに色純度が高まる（発光スペクトルの半値幅が狭くなる）。

ダブルヘテロ構造とは，LEDや半導体レーザなどにおいて，活性層の両側に活性層よりもエネルギー・ギャップが大きいクラッド層を設けた構造のこと。電子と正孔を活性層内に閉じ込める効果がある。このため，発光素子にダブルヘテロ構造を採用すると光出力を高められる。なお，活性層の片側にのみエネルギー・ギャップが大きいクラッド層を設けた構造をシングルヘテロと呼ぶ。

ผลลัพธ์ (อังกฤษ) 1:

That small band gap is extremely thin layers sandwiched between larger band gap layers structure. The potential of small band gap layers lower than surrounding (larger band gap layers), potential well (quantum well) is ready. Using active layer to emit light LEDs and semiconductor lasers, quantum-well structure. Multiple quantum wells （ MQW：multi quantum well ） call hovers over multiple quantum well structures.

As blue LEDs,On improving the structure of series Crystal Gan quantum-well structures, layer has evolved. As Gan-would be MIS （ metal-insulatorsemiconductor ）, pn junction type double hetero structure, adopted the single quantum well double hetero structure, double-heterojunction structure employing multiple quantum wells, increasing brightness and color purity. MIS blue LED is during p-type GaN films cannot be prepared, developed and commercialized is had. Had the disadvantage that get hundreds of mcd luminous intensity. After that,blue LEDs for p-type GaN films you have prepared, adopted the pn junction type double hetero structure became feasible. We MIS structure compared to the luminance of about 10 times in 1 cd. Replace in multiple quantum well structures and luminous intensity increases further, even more color purity （ narrowing spectrum emission FWHM ）.

And double-heterojunction structures, LED and laser diodes,It established the energy gap is larger than the active-layer cladding layer on both sides of the active layer structure. To be effective in the active layer to confine the electron and hole. For this reason, adopt double-heterojunction structure light-emitting devices with enhanced light output. Called single-hetero structure, with large energy gap cladding layer on only one side of the active layer.

ผลลัพธ์ (อังกฤษ) 2:

That the structure is sandwiched between layers having a larger band gap and a very thin layer has a small band gap. Potential of the layers having a smaller band gap is lower than the (layer band gap is large) around, has been able to (quantum well) the potential well. In such a semiconductor laser or LED, is used for the active layer for emitting light quantum well structure. Referred to as: (multi quantum well MQW) multiple quantum well structure is overlaid multiple quantum well. And blue LED has been developed by improving the layer structure of GaN-based crystal layer and the quantum well structure. As it goes to the double heterostructure employing double heterostructure employing MIS (metal-insulatorsemiconductor) structure, pn junction type double hetero structure, a single quantum well, a multiple quantum well, the color purity and brightness increases the GaN-based LED. A time when p-type GaN layer can not be made, a blue LED of the MIS structure have been developed and commercialized. There is a problem only several hundred mcd not be obtained intensity. Since then, was able to produce a p-type GaN layer, a blue LED employing a pn junction-type double hetero structure becomes feasible. It was achieved 1cd which is a light-emitting luminance of about 10 times compared to the MIS structure. Luminous intensity increases further and replaced with a multiple quantum well structure, the color purity is further increased (full width at half maximum of the emission spectrum is narrowed). A double heterostructure, such as in a semiconductor laser or LED, that the structure in which a cladding layer energy gap larger than that of the active layer on both sides of the active layer. Has the effect of confining in the active layer electrons and holes. Therefore, it is increased the light output by adopting a double heterostructure light emitting element. In addition, I call the single hetero structure provided with a cladding layer energy gap is large only on one side of the active layer.

ผลลัพธ์ (อังกฤษ) 3:

Layer sandwiched between the big structure of small band gap band gap layer is very thin. The surrounding small potential layer is larger in band gap layer (lower than the band gap ， potential well (well). In the semiconductor laser ， LED is used as the active layer and the quantum well structure for radiating light. Multiple quantum well structure in which a plurality of quantum well layers (multi quantum well MQW). The LED ， too blueDeveloped by improving the structure of the GaN system crystal layer, such as a quantum well structure. The system GaN LED (metal insulator semiconductor structure MIS) ， double PN junction type double hetero structure ， ， single quantum well is adopted as the ， multiple quantum wells by adopting the double heterojunction structure increases the brightness and color purity. Blue LED MIS structure at the time of ， p-type GaN film can not be produced by ， developed and commercialized. The light intensity is not obtained was only a few hundred MCD. Then ，For ， can be made to the p-type film GaN double PN junction type structure is adopted, which can be realized LED blue. Compared with the MIS structure can achieve a CD with the light emission luminance is about 10 times. In the multiple quantum well structure with increased emission intensity and improved color purity ， half-width of spectrum becomes narrower. ， too and the double heterojunction structure in ， semiconductor laser and LEDIt is provided with the structure of the active layer is larger than the energy gap of the cladding layer on both sides of the active layer. Electron trap effect, and there is a hole in the active layer. This ， for enhanced light output to adopt a double heterostructure light emitting element. In ， only on one side of the active layer is provided with a large energy gap and the clad layer is called a single hetero structure. Too