研究了调制掺杂AlxGa1-xN/GaN异质结中与二维电子气 (2DEG) 有关的光致发光,发现温度40 K时Al0.22Ga0.78N/GaN 异质结中2DEG 与光激发空穴复合形成的发光峰位于3.448 eV, 低于GaN 自由激子峰45 meV.由于AlxGa1-xN/GaN 界面极强的压电极化场的影响,光激发空穴很快扩散进GaN 平带区,导致2DEG 与光激发空穴复合几率很低.在GaN 中接近Al0.22Ga0.78N/GaN 界面处插入Al0.12Ga0.88N 限制层用于抑制光激发空穴的扩散,从而大大增强了2DEG发光峰的强度.还研究了2DEG发光峰随温度和光激发强度的变化.
Photoluminescence (PL) of modulation-doped Al0.22Ga0.78N/GaN heterostructures was investigated. The PL peak related to recombination between the two-dimensional electron gases (2DEG) and photoexcited holes is located at 3.448 eV at 40 K, which is 45 meV below the free exciton (FE) emission in GaN. The intensity of the 2DEG PL peak is enhanced significantly by incorporating a thin Al0.12Ga0.88N layer into the GaN layer near the heterointerface to suppress the diffusion of photoexcited holes.
参考文献
| [1] | Yuan Y R;Mohammed K et al.[J].Applied Physics Letters,1984,45(07):739. |
| [2] | Yuan Y;Pudensi M A A et al.[J].Journal of Applied Physics,1985,58(01):397. |
| [3] | Bernardini F.;Vanderbilt D.;Fiorentini V. .SPONTANEOUS POLARIZATION AND PIEZOELECTRIC CONSTANTS OF III-V NITRIDES[J].Physical Review.B.Condensed Matter,1997(16):10024-10027. |
| [4] | Bergman J P;Monemar B;Amano H et al.[J].Applied Physics Letters,1996,69(23):3456. |
| [5] | Yu ET;Sullivan GJ;Asbeck PM;Wang CD;Qiao D;Lau SS;TIANJIN UNIV DEPT APPL PHYS TIANJIN 300072 PEOPLES R CHINA. .Measurement of piezoelectrically induced charge in GaN/AlGaN heterostructure field-effect transistors[J].Applied physics letters,1997(19):2794-2796. |
| [6] | Kovalev;Averboukh B et al.[J].Physical Review B,1996,54(04):2518. |
| [7] | Ploog K;Dohler G H .[J].Advances in Physics,1983,32:285. |
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