电化学沉积法制备ZnO厚膜工艺研究  

Study on the Process of Preparing ZnO Thick Film by Electrochemical Deposition Method

作　　者：李岗归 黄丹阳 赵小龙[1,2] 蔡亚辉 贺永宁[1,2] LI Ganggui;HUANG Danyang;ZHAO Xiaolong;CAI Yahui;HE Yongning(School of Microelectronics,Xi’an Jiaotong University,Xi’an 710049,China;The Key Lab of Micro-Nano Electronics and System Integration,Xi’an Jiaotong University,Xi’an 710049,China)

机构地区：[1]西安交通大学微电子学院,西安710049 [2]西安交通大学微纳电子与系统集成重点实验室,西安710049

出　　处：《人工晶体学报》2024年第6期1069-1077,共9页Journal of Synthetic Crystals

基　　金：国家自然科学基金(62004158)。

摘　　要：X射线具有较高的光子能量,这使得其在ZnO材料中具有大的穿透深度,因此为了更有效地探测X射线,需要制备出微米甚至百微米厚度的ZnO膜。本文采用电化学沉积法快速制备14.85μm厚的ZnO膜。实验结果表明,沉积电势和电极材料会显著影响ZnO膜的沉积速率与表面形貌。随着沉积电势的升高,ZnO形貌由六角柱状结构变为片状结构,当电势过大时会有大量氢气生成,导致薄膜孔洞增加而无法成膜。使用金属Pt为阳极电极时,溶液会逐渐酸化,导致ZnO在沉积的同时也会溶解,当二者速率相一致时,ZnO膜厚便不再增加,因此不适合生长ZnO厚膜。而使用金属Zn为阳极电极时,溶液的pH值基本保持不变,更适合生长ZnO厚膜。使用金属Zn作为阳极电极,沉积电势为0.65 V,电解液浓度为0.4 mol/L时,实现了1 h生长14.85μm的ZnO厚膜。在5 V偏压下,基于ZnO厚膜的探测器对加速电压为40 kV的X射线的响应度可达66.8μC·Gy^(-1)·cm^(-2)。X-rays have high photon energy,which results in a significant penetration depth in ZnO materials.Therefore,in order to detect X-rays effectively,it is necessary to prepare ZnO films with a thickness of micrometers or hundreds of micrometers.In this paper,a 14.85μm-thick ZnO film was rapidly prepared by electrochemical deposition method.The experimental results show that the deposition potential and electrode material have a significant effect on the deposition rate and surface morphology of ZnO films.With increasing the deposition potential,the morphology of ZnO changes from hexagonal columnar to lamellar structure.When the potential is too high,a large amount of hydrogen is generated,resulting in an increase in the number of holes in the film that prevent it from forming.When using metal Pt as the anode electrode,the solution will gradually acidify,resulting in the dissolution of ZnO as it is deposited,and when the rates of the two coincide,the ZnO film thickness will no longer increase,making it unsuitable for growing ZnO thick films.In contrast,when using metal Zn as the anode electrode,the pH of the solution remains essentially unchanged,which is more suitable for growing ZnO thick films.A ZnO thick film of 14.85μm was grown for 1 h using metallic Zn as the anode electrode with a deposition potential of 0.65 V and an electrolyte concentration of 0.4 mol/L.When biased at 5 V,the ZnO thick film based detector has been shown to achieve a responsivity of 66.8μC·Gy^(-1)·cm^(-2)to X-rays with an accelerating voltage of 40 kV.

关 键 词：ZnO厚膜 电化学沉积法 X射线探测器 沉积电势 Zn电极 沉积速率 

分 类 号：O78[理学—晶体学]