沉积温度、压力对CVDZnS晶粒尺寸及性能的影响

Effects of Deposition Temperature and Pressure on Grain Size and Properties of CVDZnS

通过控制H2S流量(2±1)L/min、氩气流量(35±2)L/min,在不同沉积温度[(650±10)、(670±10)、(700±10)℃]、不同沉积压力[(5000±200)、(7000±200)、(9000±200)Pa]工艺条件下采用化学气相沉积法制备出原生ZnS(CVDZnS)样品。利用X射线衍射、金相显微镜、Spectrμm100 Fourier红外变换光谱仪对CVDZnS样品分别进行了物相分析、微观晶粒形貌观察以及2~15μm波段的红外透过率测试。结果表明:CVDZnS主要以立方相形式存在,有少量六方相,沉积生长的优先取向为s(111);金相分析表明在沉积压力为(5000±200)和(7000±200)Pa时,随着温度的升高平均晶粒尺寸有增大趋势,最大平均纵向晶粒尺寸值为15.5μm。平均纵向晶粒尺寸和平均横向晶粒尺寸的比值越接近"1",对于提高材料弯曲强度越有利。确定了在沉积温度为(670±10)℃、沉积压力为(7000±200)Pa工艺条件下,制备的CVDZnS可以有效提高2~5、7~10μm的平均透过率(~72.15%),降低6.0μm左右的吸收。

CVDZnS samples were prepared by a chemical vapor deposition method at different deposition temperatures(i.e.,(650±10),(670±10),(700±10)℃)and pressures(i.e.,(5000±200),(7000±200),(9000±200))Pa as well as a H2S flowrate of(2±1)L/min and an argon flowrate of(35±2)L/min.The CVDZnS samples were analyzed by X-ray diffraction,metallographic microscopy and Fourier transform infrared spectroscopy,microscopic grain morphology and infrared transmittance measurement at 2–15μm.Based on the XRD characterization,CVDZnS mainly exists in the form of cubic phase with a small amount of hexagonal phase and the preferential orientation of deposition growth is s(111).The metallographic analysis indicates that the average grain size increases with the increase of temperature when the deposition pressure is(5000±200)and(7000±200)Pa,and the maximum average longitudinal grain size is 15.5μm.The bending strength test data show that the ratio of average longitudinal grain size to average transverse grain size is closer to"1",which is more advantageous to increase the bending strength of materials.In addition,the CVDZnS prepared at(670±10)℃and(7000±200)Pa can effectively improve the average transmittance of 2–5 and 7–10μm(i.e.,72.15%)and reduce the absorption at 6.0μm.