不同溅射功率制备的Zn_(0.97)Co_(0.03)O薄膜的结构和光学性质研究
|
摘要
采用磁控溅射法在不同射频功率下制备了Zn_(0. 97)Co_(0. 03)O薄膜。利用X射线衍射(XRD)、拉曼光谱(Raman)、紫外-可见光谱和室温光致发光谱对薄膜进行了表征。XRD和Raman结果表明,Zn_(0. 97)Co_(0. 03)O薄膜为六方纤锌矿结构,沿(002)晶面择优取向。随着溅射功率的增大,薄膜的(002)晶面择优取向增强,晶化程度提高,晶粒尺寸增大。不同溅射功率制备的Zn_(0. 97)Co_(0. 03)O薄膜均具有较高的可见光透过率。随溅射功率增加,光学带隙减小,光吸收边红移。光致发光谱表明不同溅射功率制备的Zn_(0. 97)Co_(0. 03)O薄膜均具有较强的带边紫外发光峰。随着溅射功率的增加,该发光峰的峰位发生红移,且峰强度增强。以上研究结果表明,溅射功率对Zn_(0. 97)Co_(0. 03)O薄膜的生长速率、结晶质量及光学性能有明显影响,但不会影响薄膜的成分。
Zn_(0. 97)Co_(0. 03)O thin films were prepared by magnetron sputtering at different RF sputtering power. The films were characterized by X ray diffraction (XRD), Raman spectroscopy (Raman), UV-Vis spectroscopy and room temperature photoluminescence. The results of XRD and Raman showthat the Zn_(0. 97)Co_(0. 03)O thin films possess hexagonal wurtzite structure with preferred orientation of (002) along the c-axis perpendicular to the substrate. With the increase of RF sputtering power,the preferred orientation of (002) crystal faces is obviously enhanced,the degree of crystallization is increased,and the grain size is increased.The Zn_(0. 97)Co_(0. 03)O films prepared with different RF sputtering power have higher visible light transmittance. As the RF sputtering power increases, the optical band gap decreases, and the light absorption edge appears red shift. The room temperature photoluminescence spectrum shows that the Zn_(0. 97)Co_(0. 03)O films prepared by different RF sputtering power have strong band edge ultraviolet emission peak. The peak position is red shifted and the peak intensity increases with the RF sputtering power increases. The above results showthat the sputtering power has a significant effect on the growth rate,crystal quality and optical properties of Zn_(0. 97)Co_(0. 03)O films,but has little effect on the composition of the films.
Zn_(0. 97)Co_(0. 03)O thin films were prepared by magnetron sputtering at different RF sputtering power. The films were characterized by X ray diffraction (XRD), Raman spectroscopy (Raman), UV-Vis spectroscopy and room temperature photoluminescence. The results of XRD and Raman showthat the Zn_(0. 97)Co_(0. 03)O thin films possess hexagonal wurtzite structure with preferred orientation of (002) along the c-axis perpendicular to the substrate. With the increase of RF sputtering power,the preferred orientation of (002) crystal faces is obviously enhanced,the degree of crystallization is increased,and the grain size is increased.The Zn_(0. 97)Co_(0. 03)O films prepared with different RF sputtering power have higher visible light transmittance. As the RF sputtering power increases, the optical band gap decreases, and the light absorption edge appears red shift. The room temperature photoluminescence spectrum shows that the Zn_(0. 97)Co_(0. 03)O films prepared by different RF sputtering power have strong band edge ultraviolet emission peak. The peak position is red shifted and the peak intensity increases with the RF sputtering power increases. The above results showthat the sputtering power has a significant effect on the growth rate,crystal quality and optical properties of Zn_(0. 97)Co_(0. 03)O films,but has little effect on the composition of the films.
引文
[1]Ashrafi A,Jagadish C.Review of zinc blende Zn O:stability of metastable Zn O phases[J].Journal of Applied Physics,2007,102:71101.
[2]Saleh W R,Saeed N M,Twej W A,et al.Synthesis sol-gel derived highly transparent Zn O thin films for optoelectronic applications[J].Advanced M aterials,2012,2:11-16.
[3]Sharma P,Gupta A,Rao K V,et al.Ferromagnetism above room temperature in bulk and transparent thin films of M n-doped Zn O[J].Nature M aterials,2003,2:673-677.
[4]Liang H K,Yu S F,Yang H Y.Zn O random laser diode arrays for stable single-mode operation at high pow er[J].Applied Physics Letters,2010,97:241107.
[5]Paul G K,Ghosh R,Bera S K,et al.Deep level transient spectroscopy of cyanide treated polycrystalline pCu2O/n-Zn O solar cell[J].Chemical Physics Letters,2008,463:117-120.
[6]Maldonado A,Olvera M L,Asomoza R,et al.Characteristics of Zn O:Cr thin films deposited by spray pyrolysis[J].Journal of Vacuum Science&Technology A,2000,18:2098-2101.
[7]Gao W,Li Z.Zn O thin films produced by magnetron sputtering[J].Ceramics International,2004,30:1155-1159.
[8]Jia C H,Wang S,Wu Y H,et al.Epitaxial properties of Zn O thin films on La Al O3substrates by pulsed laser deposition[J].Journal of Crystal Grow th,2015,421:19-22.
[9]Singh S,Srinivasa R S,Major S S.Effect of substrate temperature on the structure and optical properties of Zn Othin films deposited by reactive rf magnetron sputtering[J].Thin Solid Films,2007,515:8718-8722.
[10]Mahdhi H,Ayadi Z B,Gauffier J L,et al.Influence of substrate temperature on the properties of nanostructured Zn O thin films grow n by RF magnetron sputtering[J].Journal of Electronic M aterial,2016,45:557-565.
[11]Jayaraman V K,Kuwabara Y M,Alvarez A M,et al.Importance of substrate rotation speed on the grow th of homogeneous Zn O thin films by reactive sputtering[J].M aterials Letters,2016,169:1-4.
[12]Srinatha N,No Y S,Kamble V B,et al.Effect of RFpow er on the structural,optical and gas sensing properties of RF-sputtered Al doped Zn O thin films[J].RSC Advances,2016,6:9779-9788.
[13]Wong L H,Lai Y S.Effects of radio frequency power on structural,optical,and electronic properties of sputter-deposited Zn O:B thin films[J].Applied Physics A,2018,124:462.
[14]Yoshikawa H,Adachi S.Optical constants of Zn O[J].Japanese Journal of Applied Physics,1997,36:6237-6243.
[15]Kim C E,Moon P,Kim S,et al.Effect of carrier concentration on optical bandgap shift in Zn O:Ga thin films[J].Thin Solid Films,2010,518:6304-6307.
[2]Saleh W R,Saeed N M,Twej W A,et al.Synthesis sol-gel derived highly transparent Zn O thin films for optoelectronic applications[J].Advanced M aterials,2012,2:11-16.
[3]Sharma P,Gupta A,Rao K V,et al.Ferromagnetism above room temperature in bulk and transparent thin films of M n-doped Zn O[J].Nature M aterials,2003,2:673-677.
[4]Liang H K,Yu S F,Yang H Y.Zn O random laser diode arrays for stable single-mode operation at high pow er[J].Applied Physics Letters,2010,97:241107.
[5]Paul G K,Ghosh R,Bera S K,et al.Deep level transient spectroscopy of cyanide treated polycrystalline pCu2O/n-Zn O solar cell[J].Chemical Physics Letters,2008,463:117-120.
[6]Maldonado A,Olvera M L,Asomoza R,et al.Characteristics of Zn O:Cr thin films deposited by spray pyrolysis[J].Journal of Vacuum Science&Technology A,2000,18:2098-2101.
[7]Gao W,Li Z.Zn O thin films produced by magnetron sputtering[J].Ceramics International,2004,30:1155-1159.
[8]Jia C H,Wang S,Wu Y H,et al.Epitaxial properties of Zn O thin films on La Al O3substrates by pulsed laser deposition[J].Journal of Crystal Grow th,2015,421:19-22.
[9]Singh S,Srinivasa R S,Major S S.Effect of substrate temperature on the structure and optical properties of Zn Othin films deposited by reactive rf magnetron sputtering[J].Thin Solid Films,2007,515:8718-8722.
[10]Mahdhi H,Ayadi Z B,Gauffier J L,et al.Influence of substrate temperature on the properties of nanostructured Zn O thin films grow n by RF magnetron sputtering[J].Journal of Electronic M aterial,2016,45:557-565.
[11]Jayaraman V K,Kuwabara Y M,Alvarez A M,et al.Importance of substrate rotation speed on the grow th of homogeneous Zn O thin films by reactive sputtering[J].M aterials Letters,2016,169:1-4.
[12]Srinatha N,No Y S,Kamble V B,et al.Effect of RFpow er on the structural,optical and gas sensing properties of RF-sputtered Al doped Zn O thin films[J].RSC Advances,2016,6:9779-9788.
[13]Wong L H,Lai Y S.Effects of radio frequency power on structural,optical,and electronic properties of sputter-deposited Zn O:B thin films[J].Applied Physics A,2018,124:462.
[14]Yoshikawa H,Adachi S.Optical constants of Zn O[J].Japanese Journal of Applied Physics,1997,36:6237-6243.
[15]Kim C E,Moon P,Kim S,et al.Effect of carrier concentration on optical bandgap shift in Zn O:Ga thin films[J].Thin Solid Films,2010,518:6304-6307.