非晶掺氧氮化硅薄膜中N-Si-O发光缺陷态的研究

发布时间：2018-04-19 04:23

  本文选题：光致发光 + a-SiNx∶O薄膜　； 参考：《南京大学学报(自然科学)》2017年03期

【摘要】：在室温下利用等离子体增强化学气相淀积(PECVD)方法制备出非晶掺氧氮化硅(a-SiN_x∶O)薄膜.通过改变硅烷(SiH_4)和氨气(NH_3)流量比R,可实现薄膜光致发光(PL)峰位在2.06~2.79eV可见光能量范围内的波长调制.光吸收谱中光吸收峰位与PL峰位重叠,表明薄膜发光来源于光吸收边以下0.65eV左右处的缺陷态.通过对傅里叶变换红外光谱(FTIR)的键浓度分析和X射线光电子能谱(XPS)Si 2p峰的分峰拟合,发现薄膜PL强度的增强与N-Si-O键合浓度的升高紧密相关.R=1∶4时,PL强度与N-Si-O键合浓度同时达到最大.进一步证明了a-SiN_x∶O薄膜中的发光缺陷态与N-Si-O键合结构密切相关.此外,PL峰位随流量比R的增大而发生红移的现象可能源自于N-Si-O组态转变造成的缺陷态密度最大位置处的能级偏移和光学带隙变窄引起的价带顶上移.
[Abstract]:Amorphous silicon nitride doped silicon nitride (a-SiN x x O) thin films were prepared by plasma enhanced chemical vapor deposition (PECVD) at room temperature.By changing the flow ratio of SiH4) and NH3), the wavelength modulation of photoluminescence peak of thin film can be realized in the range of visible energy of 2.06~2.79eV.The optical absorption peaks overlap with the PL peaks in the optical absorption spectra, which indicates that the photoluminescence originates from the defect states around 0.65eV below the optical absorption edge.By analyzing the bond concentration of Fourier transform infrared spectroscopy (FTIR) and fitting the X ray photoelectron spectroscopy (XPS) with the peak of XPSN Si 2p,It is found that the enhancement of PL intensity is closely related to the increase of N-Si-O bonding concentration.It is further proved that the luminescent defects in a-SiN_x:O films are closely related to the N-Si-O bonding structure.In addition, the redshift of PL peak position with the increase of flow ratio R may be due to the energy level shift at the maximum position of defect state density caused by the N-Si-O configuration transition and the upward shift of the valence band caused by the narrowing of the optical band gap.
【作者单位】： 南京理工大学泰州科技学院;南京大学电子科学与工程学院;南京大学固体微结构物理国家重点实验室;
【基金】：江苏省高校自然科学研究面上项目(14KJB510014) 南京大学固体微结构物理国家重点实验室开放课题基金(M29026) 江苏省“青蓝工程”
【分类号】：TB383.2;TQ127.2
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本文编号：1771573