Al掺杂半导体Mg2Si薄膜的制备及电学性质

采用磁控溅射方法和热处理工艺在Si衬底上制备了不同Al质量分数的Mg2Si薄膜,研究了不同Al质量分数对Mg2Si薄膜结构及其电学性质的影响.通过X射线衍射仪(XRD)、扫描电子显微镜(SEM)和四探针测试仪对Al掺杂Mg2Si薄膜的晶体结构、表面形貌和电学性质进行表征和分析.结果表明:采用磁控溅射技术在Si衬底上成功制备了不同Al质量分数的Mg2Si薄膜,样品表面表现出良好的连续性,在Mg2Si (220)面具有择优生长性.随着质量分数的增加,结晶度先增加后降低,晶粒尺寸减小,且在Al质量分数为1.58％时结晶度最好.此外,样品电阻率也随着Al质量分数的增加逐渐降低,表明Al掺杂后的Mg2Si薄膜具有更好的导电性,这对采用Mg2Si薄膜研制半导体器件有着重要的意义.

Preparation and Electrical Properties of Al Doped Semiconductor Mg2Si Thin Films

The Mg2Si thin films doped with different Al mass fractions were prepared on the Si substrates by magnetron sputtering method and heat processing technology.The effects of different Al mass fractions on the structure and electrical properties of the Mg2Si thin films were studied.The crystal structure,surface topography and electrical property of the Mg2Si thin films with different Al mass fractions were characterized and analyzed by X-ray diffractometer (XRD),scanning electron microscope (SEM) and four-point probe.The results show that the Mg2Si thin films with different Al mass fractions are successfully prepared by magnetron sputtering technique on the Si substrate,and the surface of the sample shows good continuity.It is found that the Mg2Si film has only one preferred orientation of Mg2Si (220).With the increase of mass fractions,the crystallinity increases first and then decreases,and the grain size is reduced.The crystallinity is the best with 1.58％ Al mass fractions.The resistivity of the sample also decreases with the increase of Al mass fractions,indicating that Al doped Mg2Si thin films have better electrical conductivity,which is significant to the development of semiconductor devices using Mg2Si thin films.