High density lanthanum hexaboride(LaB_(6))polycrystalline with(100)preferred orientation was prepared by spark plasma sintering(SPS)using LaB_(6) nanocubes as raw materials in this work.Microstructure and thermionic e...High density lanthanum hexaboride(LaB_(6))polycrystalline with(100)preferred orientation was prepared by spark plasma sintering(SPS)using LaB_(6) nanocubes as raw materials in this work.Microstructure and thermionic electron emission property of LaB_(6) polycrystalline were investigated detailedly.The results show that the LaB_(6) polycrystalline had a relative density of 95.8%,and there was a(100)preferred orientation on its surface normal to SPS pressing direction.The work function of LaB_(6) polycrystalline normal surface was only 2.73 eV,which was almost close to the theoretical work function of LaB_(6)(100)single crystal surface.The reasons for preferential orientation of LaB_(6) polycrystalline were analyzed.展开更多
采用高温直接溅射Cu-In-Ga-Se四元合金靶材工艺制备光吸收层,通过对预溅射层温度和厚度的调控,研究铜铟镓硒(CIGS)预溅射层对直接溅射法制备CIGS薄膜的(220)择优取向调控机理。结果表明,预溅射层沉积温度逐渐降低时,CIGS薄膜X射线衍射(X...采用高温直接溅射Cu-In-Ga-Se四元合金靶材工艺制备光吸收层,通过对预溅射层温度和厚度的调控,研究铜铟镓硒(CIGS)预溅射层对直接溅射法制备CIGS薄膜的(220)择优取向调控机理。结果表明,预溅射层沉积温度逐渐降低时,CIGS薄膜X射线衍射(XRD)I_((220))/I_((112))比值从0.43增大到1.05,晶粒尺寸逐渐变大且均匀。预溅射层厚度从0增加到120 nm时,I_((220))/I_((112))比值从0.48增大到1.12。在溅射温度为室温,预溅射层厚度为80 nm时,最终获得单点10.94%的器件效率。分析预溅射层表面AFM和XPS以及器件HRETM,发现低温预溅射层引入能够显著降低衬底表面电位,电压的振幅只有25 m V,较低的表面电位促进了高温沉积CIGS(220)择优取向,同时(220)择优取向促进了化学水浴工艺时Cd离子的掺杂,最终提升了CIGS器件效率。展开更多
基金Project(51902342)supported by the National Natural Science Foundation of China。
文摘High density lanthanum hexaboride(LaB_(6))polycrystalline with(100)preferred orientation was prepared by spark plasma sintering(SPS)using LaB_(6) nanocubes as raw materials in this work.Microstructure and thermionic electron emission property of LaB_(6) polycrystalline were investigated detailedly.The results show that the LaB_(6) polycrystalline had a relative density of 95.8%,and there was a(100)preferred orientation on its surface normal to SPS pressing direction.The work function of LaB_(6) polycrystalline normal surface was only 2.73 eV,which was almost close to the theoretical work function of LaB_(6)(100)single crystal surface.The reasons for preferential orientation of LaB_(6) polycrystalline were analyzed.
文摘采用高温直接溅射Cu-In-Ga-Se四元合金靶材工艺制备光吸收层,通过对预溅射层温度和厚度的调控,研究铜铟镓硒(CIGS)预溅射层对直接溅射法制备CIGS薄膜的(220)择优取向调控机理。结果表明,预溅射层沉积温度逐渐降低时,CIGS薄膜X射线衍射(XRD)I_((220))/I_((112))比值从0.43增大到1.05,晶粒尺寸逐渐变大且均匀。预溅射层厚度从0增加到120 nm时,I_((220))/I_((112))比值从0.48增大到1.12。在溅射温度为室温,预溅射层厚度为80 nm时,最终获得单点10.94%的器件效率。分析预溅射层表面AFM和XPS以及器件HRETM,发现低温预溅射层引入能够显著降低衬底表面电位,电压的振幅只有25 m V,较低的表面电位促进了高温沉积CIGS(220)择优取向,同时(220)择优取向促进了化学水浴工艺时Cd离子的掺杂,最终提升了CIGS器件效率。
