节点文献
氧化锌薄膜的制备及压敏性质研究
Preparation and Varistor Properties of ZnO Film
【作者】 圣桂金;
【导师】 王维;
【作者基本信息】 沈阳工业大学 , 材料物理与化学, 2007, 硕士
【摘要】 氧化锌具有六角纤锌矿的晶体结构,是一种直接带隙的宽禁带半导体材料,室温下的带隙宽度为3.3eV,激子束缚能高达60meV。ZnO薄膜具有良好的透明导电性、压电性、光电性、气敏性、压敏性等性质,且易于与多种半导体材料实现集成化。因此,在平面显示器、太阳能电池透明电极、压敏元件、气敏元件等光电子器件领域有着广阔的应用前景。由于这些优异的性质,使其具有广泛的用途和许多潜在用途。近年来受到越来越多研究者的注意,成为半导体领域里的一个研究热点。本论文利用溶胶—凝胶法制备透明氧化锌薄膜。通过二水醋酸锌醇解获得不同浓度的溶胶,经过不同速度提拉镀膜,在不同热处理条件下制备不同厚度的薄膜,利用扫描电子显微镜和X射线衍射测试,结果表明薄膜表面平整、具有明显择优取向生长,并讨论不同浓度、提拉速度、预处理温度、热处理温度等对薄膜厚度的影响。通过在溶胶中加入铝盐对其进行掺杂,制备掺杂的薄膜,并对铝掺杂氧化锌薄膜进行电学特性方面的研究。研究发现掺杂铝的氧化锌薄膜,电阻率明显降低,纯氧化锌薄膜几乎不导电,掺铝后使薄膜中载流子浓度提高,薄膜的导电性能大幅度提高。本文讨论不同的掺铝量、薄膜厚度以及退火温度对电阻率的影响,并对薄膜进行扫描电子显微镜和X射线衍射测试,结果表明ZAO薄膜保持着ZnO六角纤锌矿结构,表明Al原子对Zn原子的有效替位。扫描电子显微镜观察到样品表面相对平整、致密,但仍可以看出其表面有不规则的呈较黑的凹陷部分和凸起部分呈白色的衬度,这是因为Al3+与Zn2+的离子半径不同,Al3+代替Zn2+产生的微细孔而形成的多孔结构。利用磁控溅射法在基片上制备底电极,然后用溶胶凝胶法在电极上制备掺铝的氧化锌薄膜,并对其进行压敏测试,研究发现:压敏电压为7.3V,非线性系数为7.9,漏电流为21.3μA。
【Abstract】 Zinc oxide have six angular wurtzite’s crystal structure which is a sort of a direct band-gap semiconductor material.The band gap width of Zinc oxide is 3.3eV in room temperature,and it’s excition binding energy is as high as 60 meV.ZnO film have nice transparent electric conductivity,piezoelectricity,photoelectricity,gas-sensitive,varistor,and it is easy to realize integration with multi-semiconductor material.Therefore,there is wide application prospects to ZnO film in the region of optoelectronic device of panel display, the transparency electrode of solar battery,voltage-sensitive element,gas-sensor and so on..Owing to these outstanding property,ZnO film have comprehensive usage and many potential usage.In recent years,more and more researchers have pay attention to it,and it became a research hotspot in semiconductor region..This paper talks about the preparation of transparent zinc oxide film by sol-gel method.Gain different consistence collosol from two water zinc acetate alcoholysis,and make thin film at the different pulling speed,under different heat treat condition,then gain the preparation of dissimilar thickness film.It proves the film is surfaceing and obviously preferred orientation growth by SEM and X-ray diffraction test.And This paper discuss the influence of film thickness in different consistence,pull rate,pretreatment temper -ature,heat treatment temperature and so on..Adding aluminium salt to collosol to get the preparation of adulterant film,and do researching in respect of electricity characteristic towards it.By research,adulterated aluminous zinc oxide film’s specific resistance obviously decrease,pure zinc oxide film hardly conduct electricity,but after adulterated aluminous,the carrier concentration of film is increased,filmy conduct electricity performance is largely increased too.This paper discuss that the influence of specific resistance by different volume of adulterating aluminum,film thickness as well as annealing temperature,and do Scanning Electron Microscope and X-ray diffraction testing towards the film.The result indicated the ZAO thin film is maintaining the ZnO hexagon spiauterite structure,indicates the Al atom to the Zn atom effective displacement,Carries on the observation surface using the scanning electron microscope to the sample to be relatively smooth,compactly,But still might see its surface to have not not regularly assumes the black hollow part,assumed the white with the bulge part the lining,Because Al3+ and the Zn2+ ionic radius is different,the vesicular structure which Al3+ replaces which Zn2+ to have the micro pore forms.Preparation bottom electrode in substrate by maguetron sputtering method, then,Preparation adulterate aluminum zinc oxide film in pole by sol-gel process method, and do voltage-sensitive testing towards it.by research,the varistor voltage is 7.3 V, non-linear factor is 7.9 and drain current is 21.3μA.