中国科学院半导体研究所机构知识库

低维金属硫族化合物大部分具有类石墨烯的结构，相比石墨烯具有天然的带隙，而且具有独特的电学和光学性质，在电子和光电子领域中具有很大的应用前景。作者通过不同方法生长了几种不同的金属硫族化合物，主要内容如下：

（1）采用钼酸钠和硒粉作为前驱体反应物，通过调节PH值，温度和时间，使用水热法制备了团簇状MoSe₂。扫描电子显微镜（SEM），透射电子显微镜（TEM）和X射线衍射仪（XRD）测试结果显示，所制备的样品是2H-MoSe₂，样品具有花团状结构，直径约为500 nm，元素Se和Mo的平均原子比为2.68。

（2）使用团簇状MoSe₂制备了简易器件，器件具有良好的导电性，首次探测了材料对红光的光响应性质，材料在红光照射下能产生大的光电流，具有可重复性的稳定的光响应性质。当光强密度增加时，红光照射下的光电流同样的增大。另外我们还研究了材料在低温下的性能，在温度低至153 K时器件仍然表现出良好的光响应性质。

（3）通过两步法合成了具有新型的硫化钼微米环，所制备的硫化钼环的高度，宽度和外径的平均值是69 nm，0.3 μm，5.0 μm。拉曼测试结果显示微米环是由硫化钼多晶组成。我们用硫化钼微米环通过电子束曝光制备了一个器件，还测试了其在从293 K到13 K区间的不同温度的电学性质。当温度高于223 K时，电流随温度下降地很快，满足一个简单的幂指数方程。

（4）使用SnO作为前驱物通过（化学气相沉积法）CVD法制备了SnS₂片状结构，显示约10 μm六角或半六角片状结构，拉曼测试，XRD测试结果显示我们所制备的SnS₂结晶质量高。整个SnS₂片状结构的生长过程可分为三个阶段，首先是前驱物SnO沉积在衬底上，然后SnO与S反应生成SnS₂结晶核，最后在晶核上生长SnS₂。之后我们使用机械剥离法得到了100nm左右厚度的薄片，通过光刻制备出了器件，器件的绿光，红光响应测试结果显示材料对绿光反应灵敏，开光比为12.5。

Low dimensional metal chalcogenides most have the graphene-like structure,  compared to graphene, low dimensional metal chalcogenides have natural advantage which has natural band gaps. Low dimensional metal chalcogenides have unique electrical and optical properties, and have great application prospect in the field of electronics and optoelectronics. The author used different ways to grow several different metal chalcogenides, the main content of the dissertation is as follows:

(1) Sodium molybdate and selenium powder were used as precursors of reactions. Flower-like MoSe₂ were prepared by hydrothermal method, by adjusting the value of PH, temperature and time. The samples were measured with scanning electron microscope (SEM), transmission electron microscope (TEM) and X-ray diffraction (XRD). The as-prepared samples is 2H-MoSe₂, and have flower-like structure with an average diameter of about 500 nm. The mean atomic ratio of Se and Mo atoms is 2.68.

(2) An simple device was fabricated using flower-like MoSe₂. The device has good electrical conductivity, Then material was measured that light-response properties to red light for the first time. The samples under red light irradiation could produce large photocurrent, with stable repeatable light response properties. When the density of the light intensity increased, the photocurrent under the red illumination also increased. We also studied the performance of the material at low temperature. When temperature was as low as 153 K, the device still showed good light-response properties.

(3) A new structure of molybdenum sulfide micro-rings was synthesized through a two-step method. Each the mean value of height, width and diameter is 69 nm, 0.3 μm, 5.0 μm. The results of Raman measurement showed that the micro-rings consist of molybdenum sulfide polycrystalline. A device was prepared by electron beam lithography, electrical properties was also measured at different temperature range from 293 K to 13 K. When temperature was higher than 223 K, current decreased rapidly, according with a simple power equation.

(4) SnS₂ plates were sythesized using SnO as the precursor by CVD (chemical vapor deposition method). The samples showed 10 μm hexagonal or half hexagonal plates structure. The results of Raman, XRD measurements show that the crystallization of the as-prepared SnS₂ have high quality. The growth process of SnS₂ plates can be divied three stages: firstly the precursors of SnO were deposited on the substrate; then SnO and S reacted to SnS₂, forming crystal nucleus; at last SnS₂ plates grew based on the crystal nucleus. Mechanical-exfoiled method was used to get thin chips with the thickness of about 100 nm. Then a device was prepared by lithography device with thin chips. The device showed sensitive response to green light, and the ration of On/Off is far more than 12.5.