應用於光伏元件之溶膠凝膠法製備矽奈米粒子埋入式摻鋁氧化鋅薄膜之特性研究

Abstract

在我們先前的研究中，以射頻磁控濺鍍方式開發出氧化鋅/矽多層膜結構，形成的矽量子點埋入式氧化鋅薄膜成功地克服了傳統矽量子點薄膜在電性上受限於高阻値矩陣材料的特性。以此製程方式為了得到較好的矽量子點結晶，常需透過高溫的退火來達成，卻也使薄膜出現彎曲的問題，其主要是由退火過程中矽量子點由非晶轉變為結晶結構產生的膜內應力造成，將導致在薄膜與基板介面間出現局部斷路的情形並造成電阻率的增加。 因此在本篇研究中，我們提出以具有低溫製程特性的溶膠凝膠法來沉積出矽奈米粒子埋入式摻鋁氧化鋅薄膜。透過改變不同製程條件及材料參數來分析氧化鋅與摻鋁氧化鋅薄膜的物理、光學及光電特性，並以最佳光電特性的薄膜參數作為後續矽奈米粒子埋入的矩陣材料。接著以夾層方式埋入經蝕刻處理過的矽奈米粒子於摻鋁氧化鋅薄膜內，並研究埋入後薄膜特性及發現到受埋入的矽奈米粒子尺寸分布大及粒子間聚集問題影響，造成薄膜穿透度及光電特性的下降。因此在未來若能解決矽奈米粒子在蝕刻製程上的問題，此裝置將有潛力應用於太陽能電池中。

In our previous work, we developed a Si quantum dots (QDs) embedded in ZnO thin film by using a ZnO/Si multilayer structure by the radio-frequency magnetron sputtering method to overcome the issue of highly resistive nature of the traditional Si QDs embedded in Si-based dielectric matrix materials. For the better crystalline quality of Si QDs formation, a high temperature annealing process is needed. However, the film bending problem can be observed after annealing due to the volume variation from the phase transformation of amorphous to nanocrystalline Si (nc-Si) QDs, producing an interior film stress. It will lead to local broken circuit regions at the interface of film/substrate and significantly increase the resistivity. In this study, we propose to use sol-gel method to deposit the structure of Si NPs embedded in AZO matrix due to the process advantage of relatively low temperature, and analysis the effects of sol-gel derived ZnO and AZO thin films under different process conditions for better electrical properties of the embedded matrix. At last, we embed the treated nc-Si nanoparticles (NPs) in AZO thin films by the layer by layer method and investigate film’s properties and observe the problems of the aggregation and wide size distribution of Si NPs in the thin film, decreasing the film’s transparency and electrical properties. If we solve the problems mentioned above in the future, the device is a promising structure for solar cell applications.