氮气分压比对硼碳氮薄膜的组分及光学带隙的影响

Influence of N2 partial pressure on composition and optical band gapof boron carbon nitride thin films

采用射频磁控溅射方法以不同的氮气分压比（1/10-2/3）制备出一组硼碳氮薄膜.傅里叶变换红外光谱（FTIR）和X射线光电子能谱（XPS）测量发现样品的组成原子之间均实现了原子级化合.XPS测量结果表明,所有样品中的B、N原子比近似为1∶1,其化学配比为BCxN（0.16〈x〈1.46）.紫外/可见/近红外分光光度计用于测量样品的吸收光谱.由吸收谱线在低能区域（2.0-3.0 eV）的光吸收,利用关系作图法求出光学带隙Eopt范围为0.17-0.83 eV.氮气分压比对薄膜的组分和光学带隙有很大影响,其通过改变薄膜组分而影响光学带隙,并且碳原子数小的样品具有较宽的光学带隙.以氮气分压比为1/3条件下制备的样品中碳原子数最小,它的光学带隙最宽为0.83 eV.

Boron carbon nitride thin films were deposited by RF magnetron sputtering at different N2 partial pressure（1/10～2/3）.Fourier transform infrared spectroscopy（FTIR） and X-ray photoelectron spectroscopy（XPS） results suggested that the films were atomic-level hybrids composed of B,C and N atoms.The compositions and absorption properties of samples were measured by XPS and a UV/VIS/NIR spectrometer,respectively.XPS measurements indicate the atomic ratio of B and N in the thin films is always near 1∶1.And the compositions of samples classified by stoichiometry are BCxN（0.16〈x〈1.46）.Their optical band gaps obtained from absorption properties（2.0～3.0 eV） were in the range of 0.17 ～ 0.83 eV.The N2 partial pressure was shown to have important effect on the compositions and optical band gap of boron carbon nitride thin films,whichis determined by changing compositions.And the lower the atomic number of C in the thin films,the wider the optical band gap.The boron carbon nitride thin films that were deposited at the N2 partial pressure of 1/3,possessed the lowest atomic number of C and the widest optical band gap of 0.83 eV.