二维半导体材料的生长和光电性能研究  

Growth and optoelectronic property of two-dimensional semiconductors

作　　者：黎博 魏钟鸣 

机构地区：[1]中国科学院半导体研究所半导体超晶格国家重点实验室,北京100083

出　　处：《科学通报》2017年第33期3829-3837,共9页Chinese Science Bulletin

基　　金：国家自然科学基金优秀青年科学基金(61622406)资助

摘　　要：二维过渡金属硫族化合物纳米材料由于是不同带隙的半导体,同时有些在地球上储量丰富,受到人们广泛的关注.在本文中,介绍了用于二维材料场效应晶体管制备的光刻图形转移技术.该方法可以低成本、简单、有效地获得晶体管,同时对二维材料的损伤较小,可以获得高性能的二维材料晶体管;其次,介绍了Co掺杂MoS_2双层纳米片的生长及电学输运研究,可以通过控制生长过程中硫的浓度来改变纳米片的形貌,随着温度的升高,最终可以获得CoS_2/MoS_2六边形结构,电学测试表明Co掺杂MoS_2双层纳米片显n型,而CoS_2/MoS_2六边形结构具有很高的电导率;还介绍了垂直双层SnS_2/MoS_2异质结的气相生长及光电性能研究,这种异质结具有很大的带阶,能带结构呈现Ⅱ型,在异质结区域,出现了强烈的光致发光谱淬灭,这种异质结与相应的单体材料相比,具有增强的光电性能.最后,对二维材料的未来研究进行一些展望.Two-dimensional （2D） nanosheets of layered transition metal dichalcogenides （TMDs） have received significant attention because some of them are semiconductors with sizable band gaps and are naturally abundant. Here, we report the photolithographic-pattern transfer （PPT） technology used to fabricate FETs of two-dimensional materials. To explore the electrical properties and realize functional optoelectronics and electronics from semiconductors, the fabrication of devices （such as field-effect transistors （FET）, diodes and Hall bars） and integrated circuits is necessary and important. An essential step in fabricating micro-/nanoelectronics is making the metal electrode arrays. Such a PPT method can be used to efficiently design and prepare complicated electrode arrays for electronics and optoelectronics, and is especially suitable for 2D materials. Few-layer MoS2 made by electron beam lithography （EBL）, gold-wire mask moving （GWM）, and this method are used as templates for comparison. The mobility of our thin MoS2 flake is comparable to the results of devices from EBL and better than the results of the GWM method. Further complicated device applications such as a top-gate FET, a Hall bar, and heterostructure transistors could also be easily realized based on such a method. We also report the growth and electric transport of Co doped MoS2 bilayer. As the initial loading of the sulfur increases, the morphology of the CoxMo1-xS2 （0〈x〈1） nanosheets becomes hexagons from David stars step by step at 680℃. We find that Co atoms mainly distribute at the edge of nanosheets. When the temperature increases from 680 to 750℃, high-quality cubic pyrite-type crystal structure CoS2 grows on the surface of CoxMO1-xS2 nanosheet gradually and forms hexagonal film induced by the nanosheet. Electrical transport measurements reveal that the Co,MO1-xS2 nanosheets and CoS2 films exhibit n-type semiconducting transport behavior and half-metallic behavior, respectively. Theoretical calculations of the

关 键 词：二维半导体 二硫化钼 气相生长 光电器件 

分 类 号：TN304[电子电信—物理电子学]