摘要
采用基于密度泛函理论的第一性原理平面波赝势的方法,通过搜寻Mg原子在硅Si(220)晶面上的最佳吸附位置,计算Mg/Si(220)体系的吸附能、电子态密度、电子布居和功函数等,系统研究了Mg原子在Si(220)表面的吸附过程.结果表明:Si表面Mg原子的最稳定吸附位置为Si(220)晶面的穴位,此时吸附能最低.同时,Mg/Si(220)体系中Mg原子的2p和3s轨道电子与Si原子的3s和3p轨道电子间的强相互作用使体系的电子布居和功函数发生改变.
The process of Mg adsorption on the Si(220) surface was investigated by calculating the adsorption energies,densities of states(DOS),electron populations and work functions using first-principles based on the density functional theory(DFT)with the plane wave pseudo potential method to search for the optimal adsorption sites of Mg atom on Si(220) crystal surface. The results show that the most stable site of Mg atom on the Si(220) surface is the hollow site of crystal surface,where the system has the lowest adsorption energy. At the same time,the interaction between 2 p,3 s states of Mg atom and 3 s,3 p states of Si atom in the Mg/Si(220) system changes the electron populations and work function of the system.
引文
[1]宋春燕,贵永亮,胡宾生,等.金属硅化物及其复合材料的研究进展[J].材料导报,2009,12(23):101-103.SONG C Y,GUI Y L,HU B S,et al. Research progress of metal silicidebased composites[J]. Materials Review,2009,12(23):101-103(in Chinese).
[2] WANG Y,WANG X N,MEI Z X,et al. Epitaxial orientation of Mg2Si(110)thin film on Si(111)substrate[J]. Journal of Applied Physics,2007,102(12):16965.
[3] XIAO Q,QUAN X,SHEN X,et al. Effects of magnesium film thickness and annealing temperature on formation of Mg2Si films on silicon(111)substrate deposited by magnetron sputtering[J]. Applied Surface Science,2011,257(17):7800-7804.
[4] GALKIN N G,VAVANOVA S V,MASLOV A M,et al. Solid phase growth and properties of Mg2Si films on Si(111)[J]. Thin Solid Films,2007,515(22):8230-8236.
[5] HOSONO T,MATSUZAWA Y,KURAMOTO M,et al. Simple fabrication of Mg2Si thermoelectric generator[J]. Solid State Phenomena,2003,93(5):447-452.
[6] MAHAN J E,VANOMME A,LANGOUCHE G,et al. Semiconducting Mg2Si thin films prepared by molecular-beam epitaxy[J]. Physical Review B,1996,54(23):16965.
[7] YANG M J,ZHANG L,SHEN Q. Synthesis and sintering of Mg2Si thermoelectric generator by spark plasma sintering[J]. Journal of Wuhan University of Technology,2008,23(6):870-873.
[8] WITTMER M,LUTHY W,ALLMEN M. Laser induced reaction of magnesium with silicon[J]. Physical Letters A,1979,75(1/2):127-130.
[9] YING M J,ZHANG P,DU X L. First-principle study of Mg adsorption on Si(111) surfaces[J]. Chinese Physics B,2009,18(1):275-281.
[10] PENG G W,HUAN A C H,TOK E S,et al. Adsorption and diffusion of Co on the Si(001)surface[J]. Physical Review B,2006,74(19):3840-3845.
[11] CHUN Y,CHONG Y,PING H,et al. First-principles study of the adsorption and diffusion of O2on a Si(001)surface[J]. Surface Review&Letters,2012,18(6):315-321.
[12] QIAO L,WANG C,QU C Q,et al. First-principles investigation on the field emission properties of B-doped carbon nanotubes[J]. Diamond&Related Materials,2009,18(4):657-661.
[13] WELLS J C,ZHANG Z,HU T,et al. A comparative first-principles study of the adsorption of a carbon atom on copper and nickel surfaces[J].Physics Letters A,2010,374(44):4563-4567.
[14] QIAO L,WANG S M,ZHANG X M,et al. Adsorptions and diffusions of carbon atoms on the surface and in the subsurface of Co(200):A first-principles density-functional study[J]. Chinese Physics B,2014,221(8):75-80.
[15]赵建华. In、T1在Si(111)面吸附特性的第一性原理研究[D].新乡:河南师范大学,2009.ZHAO J H. First-principles Study on Adsorption Characteristics of In and T1 on Si(111)Surface[D]. Xinxiang:Henan Normal University,2009(in Chinese).
[16] ZHANG W,WU P,LI Z,et al. First-principles thermodynamics of graphene growth on Cu surfaces[J]. Journal of Physical Chemistry C,2011,115(36):17782-17787.
[17]张苗,侯贤华,王基蕴,等. Ag在Si表面吸附的第一性原理研究[J].华南师范大学学报(自然科学版),2014(5):49-53.ZHANG M,HOU X H,WANG J Y,et al. First-principles study of Ag adsorption on Si surfaces[J]. Journal of South China Normal University(Natural Science Edition),2014(5):49-53(in Chinese).