硒化鋅薄膜光激螢光穩定性之研究

Study on stability of photoluminescence of ZnSe thin films

林錦政(Jin-Jheng Lin)

指導教授 ： 王智祥

中原大學/理學院/物理研究所/碩士(2012年)

https://doi.org/10.6840/cycu201200946

摘要

此實驗的4種樣品是以分子束磊晶法在砷化鎵(001) 的基板成長有無摻雜氯和晶格有無鬆弛的硒化鋅薄膜，從室溫光激螢光光譜發現摻雜氯的硒化鋅薄膜近能隙發光強度比沒有摻雜氯的硒化鋅薄膜近能隙發光強度大，摻雜氯的硒化鋅薄膜在能量1.72~2.55 eV有一個大範圍的訊號，文獻說明這是深層能階發光。用功率密度6.1 W/cm2的雷射光照4種樣品2個小時的劣化實驗，在照光前後量測了室溫光激螢光光譜，照光2小時期間，也記錄樣品的近能隙發光或深層能階發光峰值位置的強度衰減變化，發現有摻雜氯的樣品光激螢光強度衰減比無摻雜氯的樣品小，證明把氯摻雜在硒化鋅薄膜中可以改善光激螢光的穩定度；也觀察到有應力的樣品光激螢光強度衰減比沒有應力的樣品大。

關鍵字

應力 ； 臨界厚度 ； 光激螢光 ； 晶格鬆弛 ； 非輻射復合中心 ； 劣化 ； 硒化鋅

並列摘要

Four samples of ZnSe thin films (strained films with/without Cl doping, lattice relaxed films with/without Cl doping) on semi-insulating (001) GaAs substrates grown by molecular beam epitaxy were employed to investigate the stability of photoluminescence (PL) of ZnSe thin films. Room temperature PL spectra showed that the near-band-edge emission intensity of Cl-doped ZnSe thin films is much stronger than that of undoped ZnSe thin films. A deep-level emission at around 1.72~2.55 eV with a large full width at half maximum is observed in the Cl-doped samples. Our PL degradation experiments revealed that photon irradiation with a wavelength of 401 nm and a power density of 6.1 W/cm2 cause PL degradation and the generation of nonradiative centers by photon irradiation can be greatly suppressed by incorporating Cl dopant. Besides, the samples with compressive strain showed a stronger effect on PL degradation than the samples with lattice relaxation.

並列關鍵字

ZnSe ； nonradiative center ； stress ； lattice relaxation ； critical thickness ； photoluminescence ； degradation

參考文獻

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