Influences of Inserted Layers and Extra Impurities for Nucleation Enhancement on Film Properties of Transparent Conductive Oxides

我们主要研究了以下三个主题：(1)在ZnO: Al薄膜中插入ZnO层可以得到什么效果。(2)在Zri共沉积的情况下，将Mn、Co、Cr等杂质混入ZnO: A1薄膜中会有什么影响？(3)同时沉积ZnO和In_2O_3可以制备出什么样的薄膜？对于实验对象(1)，额外添加Zn可以有效降低ZnO:Al的薄膜电阻率。这是由于ZnO生长过程中的成核增强，从而提高了Al供体的掺杂效率，同时降低了ZnO:Al微晶晶界处的电位高度。Mn、Co和Cr杂质的影响随着ZnO:Al薄膜电阻率的增大而显现。杂质的加入提高了微晶的晶粒尺寸，但载流子浓度的降低抵消了晶粒尺寸增大所带来的载流子迁移率的提高。晶界处的杂质氧化严重影响ZnO:Al薄膜的电阻率。在(3)中，我们沉积了ZnO-In2O3体系的三元化合物。非晶相出现在较宽的Zn/ in比范围内。非晶相薄膜的电阻率低于同晶相薄膜。在Al的非晶相中发现了掺杂效应，表明三元化合物的非晶相中存在外源掺杂。

We investigated mainly the following 3 thema : (1) What effect can we obtain by the insertion of ZnO layers into ZnO : Al film. (2) What effect can we find in mixing impurities such as Mn, Co and Cr into ZnO : A1 film under the codeposition of Zri. (3) What kind of film can we prepare under the simultaneous deposition of ZnO and In_2O_3.For the subject (1), extra addition of Zn was effective in decreasing the film resistivity of ZnO:Al. This was ascribed to enhanced nucleation in ZnO growth and the resultant increase of doping efficiency of Al donors, and the decrease of potential height at the grain boundaries of ZnO:Al micro crystals. The influence of Mn, Co and Cr impurities appeared as the increase of film resistivity of ZnO:Al. The grain size of micro crystal was improved by impurity adding, but the decrease of carrier concentration cancelled the increase in carrier mobility due to the increased grain size. The impurity oxidization at the grain boundaries influenced severely on the ZnO:Al film resisitivity. In (3), we deposited ternary compounds of ZnO-In2O3 system. Amorphous phase appeared in wide range of Zn/In ratio. Amorphous films showed lower resistivity than homologous crystallized phase film. The doping effect was noticed in the amorphous phase for Al. This result suggests the extrinsic doping in amorphous phase of ternary compounds.