本工作提出了脉冲激光沉积法生长 Cu2Se 热电材料薄膜中维持较高的激光切削能量密度对于实现薄膜与靶材成分等比例传输的重要性。使用较高的脉冲激光能量生长的Cu2Se薄膜具有纯的a-相,并具有与靶材相近的化学组分。这主要是因为较高的激光能量可以更加有效地引起等离子体对激光-固体直接作用的屏蔽,这可以使得靶材中的铜和硒元素的激光切削量更加接近靶材的化学计量比。由于硒具有较高的蒸汽压,降低激光能量会加强激光与固体的直接作用,从而更有效地切削硒元素,导致所沉积薄膜中产生铜缺陷。进一步讨论了所使用的氩气背景气体压力对于所生长的 Cu2Se 薄膜热电性能的影响。当使用高激光能量低背景气体压力时,所生长的薄膜具有最佳的热电性能。
The importance of the laser ablation fluence in congruent growth of Cu2Se thermoelectric thin films during pulsed laser deposition was shown in this work. By using a larger laser ablation fluence, a more consistent composition between as-grown thin films and the target material has been realized in the pulsed laser deposition of Cu2Se films. This is associated with the enhanced plasma shielding effect, which weakens direct laser-solid interaction when in-creasing laser fluence. Reducing the ablation fluence can obviously increase the amount of the copper deficiencies, due to more effective laser ablation of Se (higher vapor pressure) than that of Cu when the laser direct lasser-solid interac-tion becomes more efficient. Apart from tuning the ablation fluence, thermoelectric performances of as-grown Cu2Se thin films are further optimized as a function of the used argon background gas pressures. The maximum thermoelec-tric performance of the Cu2Se thin film can be obtained when using the highest ablation fluence (~10 J/cm2) and a low argon background pressure(~10-1 Pa).
参考文献
[1] | Huili Liu;Xun Shi;Fangfang Xu.Copper ion liquid-like thermoelectrics[J].Nature materials,20125(5):422-425. |
[2] | Huili Liu;Xun Yuan;Ping Lu;Xun Shi;Fangfang Xu;Ying He;Yunshan Tang;Shengqiang Bai;Wenqing Zhang;Lidong Chen;Yue Lin;Lei Shi;He Lin;Xingyu Gao;Xingmin Zhang;Hang Chi;Ctirad Uher.Ultrahigh Thermoelectric Performance by Electron and Phonon Critical Scattering in Cu_2Se_(1-x)l_x[J].Advanced Materials,201345(45):6607-6612. |
[3] | 陈立东;熊震;柏胜强.纳米复合热电材料研究进展[J].无机材料学报,2010(6):561-568. |
[4] | 詹斌;兰金叻;刘耀春;丁靖轩;林元华;南策文.氧化物热电材料研究进展[J].无机材料学报,2014(3):237-244. |
[5] | G.JEFFREY SNYDER;ERIC S.TOBERER.Complex thermoelectric materials[J].Nature materials,20082(2):105-114. |
[6] | Lv, Yanhong;Chen, Jikun;Zheng, Ren-Kui;Shi, Xun;Song, Junqiang;Zhang, Tiansong;Li, Xiaomin;Chen, Lidong.(001)-oriented Cu2-ySe thin films with tunable thermoelectric performances grown by pulsed laser deposition[J].CERAMICS INTERNATIONAL,20156(6):7439-7445. |
[7] | Jikun Chen;Alexandra Palla-Papavlu;Yulong Li;Lidong Chen;Xun Shi;Max Dobeli;Dieter Stender;Sascha Populoh;Wenjie Xie;Anke Weidenkaff;Christof W. Schneider;Alexander Wokaun;Thomas Lippert.Laser deposition and direct-writing of thermoelectric misfit cobaltite thin films[J].Applied physics letters,201423(23):231907-1-231907-5. |
[8] | Willmott PR.;Huber JR..Pulsed laser vaporization and deposition[J].Reviews of Modern Physics,20001(1):315-328. |
[9] | S. Wicklein;A. Sambri;S. Amoruso;X. Wang;R. Bruzzese;A. Koehl;R. Dittmann.Pulsed laser ablation of complex oxides: The role of congruent ablation and preferential scattering for the film stoichiometry[J].Applied physics letters,201213(13):131601-1-131601-5. |
[10] | Sturm K.;Krebs HU..Quantification of resputtering during pulsed laser deposition[J].Journal of Applied Physics,20012(2):1061-1063. |
[11] | S. Fahler;K. Sturm;H.-U. Krebs.Resputtering during the growth of pulsed-laser-deposited metallic films in vacuum and in an ambient gas[J].Applied physics letters,199924(24):3766-3768. |
[12] | Gonzalo J;Siegel J;Perea A;Puerto D;Resta V;Galvan-Sosa M;Afonso CN.Imaging self-sputtering and backscattering from the substrate during pulsed laser deposition of gold[J].Physical review, B. Condensed matter and materials physics,20073(3):5435-1-5435-7-0. |
[13] | C Xu;S Wicklein;A Sambri;S Amoruso;M Moors;R Dittmann.Impact of the interplay between nonstoichiometry and kinetic energy of the plume species on the growth mode of SrTiO_3 thin films[J].Journal of Physics, D. Applied Physics: A Europhysics Journal,20143(3):034009-1-034009-12. |
[14] | Qinzhuang Liu;Jianjun Liu;Bing Li;Hong Li;Guangping Zhu;Kai Dai;Zhongliang Liu;Peng Zhang;Jianming Dai.Composition dependent metal-semiconductor transition in transparent and conductive La-doped BaSnO_3 epitaxial films[J].Applied physics letters,201224(24):241901-1-241901-5. |
[15] | Pulsed laser deposition of Bi_(2)Te_(3)-based thermoelectric thin films[J].Journal of Applied Physics,20036(6):3907-3918. |
[16] | A. Li Bassi;A. Bailini;C. S. Casari;F. Donati;A. Mantegazza;M. Passoni;V. Russo;C. E. Bottani.Thermoelectric properties of Bi-Te films with controlled structure and morphology[J].Journal of Applied Physics,200912(12):124307-1-124307-9. |
[17] | Deepak Marla;Upendra V. Bhandarkar;Suhas S. Joshi.Critical assessment of the issues in the modeling of ablation and plasma expansion processes in the pulsed laser deposition of metals[J].Journal of Applied Physics,20112(2):021101-1-021101-15. |
[18] | Wu BX;Shin YC.Modeling of nanosecond laser ablation with vapor plasma formation[J].Journal of Applied Physics,20068(8):84310-1-84310-8-0. |
[19] | Fang RR;Zhang DM;Li ZH;Li L;Tan XY;Yang FX.Laser-target interaction during high-power pulsed laser deposition of superconducting thin films[J].Physica Status Solidi, A. Applied Research,200712(12):4241-4248. |
[20] | Wittmaack K.Reliability of a popular simulation code for predicting sputtering yields of solids and ranges of low-energy ions[J].Journal of Applied Physics,20045(5):2632-2637. |
- 下载量()
- 访问量()
- 您的评分:
-
10%
-
20%
-
30%
-
40%
-
50%