PHOTOLUMINESCENCE STUDY ON Hg1-xCdxTe THIN FILM IMPLANTED WITH As ION

Photoluminescence spectra of a series of MBE-grown Hg_1-xCd_xTe samples with the same mole fraction of about x≈0.39 have been measured at different temperatures from 5 to 100 K. By aid of the temperature and exciting laser power dependence of photoluminescence peak energy and relative intensity, as well as of the comparison with other measurements, four main structures dominating in the photoluminescence spectra are attributed to band to band, D^oX, A^oX and D^oA^o transitions. A deep donor state level located at about 8.5meV below the bottom of the conduction band has been observed and is determined to be due to the arsenic-occupied mercury vacancies. Two acceptor levels located at about 14.5 meV and about 31.5 meV above the top of the valance band have also been found from the measuements, which are identified as the mercury vacancies and As in anion site, respectively.     

PHOTOLUMINESCENCE PROPERTIES OF NANO-SIZE CRYSTALLINE SILICON FILMS

Photoluminescence (PL) at low temperature is reported for nc-Si:H films grown by PECVD. A characteristic luminescence peak was observed in the wavelength range of 1.1-1.2μm. The temperature dependence of PL has been studied in the temperature range of 4.2-180 K. The PL mechanism of nc-Si:H films is discussed. The emission peak at 1.1-1.2 μm is attributed to the interface atoms between grains, and the emission peak around 0.9μm is due to a little amount of amorphous component.     

a—Si_xC_(1-x):H的光致发光和光电导低温光诱导效应

报道在相同曝光条件下,a-Si_xC_(1-x):H薄膜的光致发光(PL)和光电导(PC)的低温光诱导效应。实验结果表明:PL和PC在曝光初期迅速下降,然后各自趋于稳定;PL光谱的形状及其峰值能量位置在曝光后没有变化;低温光诱导效应经室温退火即可消除。还讨论了光诱导效应机理,导出了与实验结果符合很好的光诱导效应动力学方程。     

退火对a-SixC1-x:H薄膜带尾态的影响

本文研究了退火后的a-Si_xC_1-x:H薄膜的光致发光光谱,采用发光光谱的峰值能量与测量温度之间的关系判别带尾宽度的大小。实验表明,发光峰值能量随退火温度的升高而移向低能。用指数带尾模型计算了带尾宽度。结果表明,随着退火温度的上升带尾变小。文中对这些结果进行了讨论。 关键词：     

调制掺杂的应变In0.60Ga0.40As/In0.52Al0.48As多量子阱结构的光致发光谱研究

报道了调制掺杂的应变In_0.60Ga_0.40As/In_0.52Al_0.48As多量子阱中室温光致发光光谱.观察到n=1和2电子子带到n=1重空穴子带的强发光峰.在低温下可以观察到n=1电子子带到n=1轻空穴弱发光肩胛.通过对发光强度随激发功率及温度依赖关系以及理论模型的分析研究,认为该调制掺杂量子阱中辐射复合效率降低的主要机制是应变失配位错对载流子的陷阱作用.界面上的失配位错是陷阱的主要来源.并用静态的光致发光理论模型 关键词：     

退火对a-Si_xC_(1-x):H薄膜光学性质的影响

研究了退火对α-Si_xC_(1-x):H薄膜红外吸收和光致发光性质的影响.实验结果表明:低温退火使与氢有关的红外吸收和积分发光强度增加;而高温退火使与氢有关的红外吸收和积分发光强度减弱;同时,随着退火温度升高,光致发光光谱的峰值能量位置移向低能.文中对退火引起红外吸收和光致发光性质的变化机理进行了讨论。     

PHOTOLUMINESCENCE STUDY ON Hg1-xCdxTe THIN FILM IMPLANTED WITH As ION

Photoluminescence spectra of a series of MBE-grown Hg_1-xCd_xTe samples with the same mole fraction of about x≈0.39 have been measured at different temperatures from 5 to 100 K. By aid of the temperature and exciting laser power dependence of photoluminescence peak energy and relative intensity, as well as of the comparison with other measurements, four main structures dominating in the photoluminescence spectra are attributed to band to band, D^oX, A^oX and D^oA^o transitions. A deep donor state level located at about 8.5meV below the bottom of the conduction band has been observed and is determined to be due to the arsenic-occupied mercury vacancies. Two acceptor levels located at about 14.5 meV and about 31.5 meV above the top of the valance band have also been found from the measuements, which are identified as the mercury vacancies and As in anion site, respectively.     

调制掺杂的应变In_(0.60)Ga_(0.40)As/In_(0.52)Al_(0.48)As多量子阱结构的光致发光谱研究

报道了调制掺杂的应变In_(0.60)Ga_(0.40)As/In_(0.52)Al_(0.48)As多量子阱中室温光致发光光谱.观察到n=1和2电子子带到n=1重空穴子带的强发光峰.在低温下可以观察到n=1电子子带到n=1轻空穴弱发光肩胛.通过对发光强度随激发功率及温度依赖关系以及理论模型的分析研究,认为该调制掺杂量子阱中辐射复合效率降低的主要机制是应变失配位错对载流子的陷阱作用.界面上的失配位错是陷阱的主要来源.并用静态的光致发光理论模型对实验结果进行了解释.     

半绝缘InP的铁能级研究

本文用光致发光光谱及光激电流瞬态谱研究了掺铁半绝缘InP中的铁能级,发现被测样品可分成两类,它们分别存在着 FeI(Fe~3+/Fe~+)和 Fell(Fe~(4+)/Fe~(3+))两种不同的铁能级.这可能是由于它们分别对应于浅施主和浅受主补偿的InP半绝缘材料,亦说明有争议的Fe~(4+)是在有些半绝缘InP 中存在的     

δ掺杂的赝配HEMTAlGaAs／InGaAs／GaAs结构的光电流谱

本文首次报道了δ掺杂的赝配高电子迁移率晶体管结构（ＨＥＭＴＳ）Ａｌ０．３０Ｇａ０．７０Ａｓ／Ｉｎ０．１５Ｇａ０．８５Ａｓ／ＧａＡｓ的光电流谱研究．实验观察到了ｎ＝１重空穴子带到ｎ＝１电子子带和ｎ＝２电子子带的激子吸收峰以及ＧａＡｓ本征吸收相位变化所引起的光电流结构，并对光电流谱随温度和偏压变化的行为进行了讨论．