电化学沉积法制备ZnO厚膜工艺研究

人工晶体学报 ›› 2024, Vol. 53 ›› Issue (6): 1069-1077.

电化学沉积法制备ZnO厚膜工艺研究

李岗归^1,2, 黄丹阳^1,2, 赵小龙^1,2, 蔡亚辉^1,2, 贺永宁^1,2

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

收稿日期:2024-01-17 出版日期:2024-06-15 发布日期:2024-06-20
通信作者: 赵小龙,博士,副教授。E-mail:zhaoxiaolong@xjtu.edu.cn
作者简介:李岗归(1997—) ,男,河南省人,硕士研究生。E-mail:liganggui1997@163.com
基金资助:
国家自然科学基金(62004158)

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

LI Ganggui^1,2, HUANG Danyang^1,2, ZHAO Xiaolong^1,2, CAI Yahui^1,2, HE Yongning^1,2

1. School of Microelectronics, Xi’an Jiaotong University, Xi’an 710049, China;
2. The Key Lab of Micro-Nano Electronics and System Integration, Xi’an Jiaotong University, Xi’an 710049, China

Received:2024-01-17 Online:2024-06-15 Published:2024-06-20

摘要/Abstract

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14.85 μm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14.85 μm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66.8 μC·Gy^-1·cm^-2。

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

Abstract: 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 14.85 μm-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 14.85 μm 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 66.8 μC·Gy^-1·cm^-2 to X-rays with an accelerating voltage of 40 kV.

Key words: ZnO thick film, electrochemical deposition method, X-ray detector, deposition potential, Zn electrode, deposition rate

中图分类号:

李岗归, 黄丹阳, 赵小龙, 蔡亚辉, 贺永宁. 电化学沉积法制备ZnO厚膜工艺研究[J]. 人工晶体学报, 2024, 53(6): 1069-1077.

LI Ganggui, HUANG Danyang, ZHAO Xiaolong, CAI Yahui, HE Yongning. Study on the Process of Preparing ZnO Thick Film by Electrochemical Deposition Method[J]. JOURNAL OF SYNTHETIC CRYSTALS, 2024, 53(6): 1069-1077.

参考文献

[1] ZHAO X, HUANG D, LI G, et al. High sensitivity X-ray detector based on a 25 μm-thick ZnO film[J]. Sensors and Actuators A: Physical, 2022, 334(1): 113310.
[2] ENDO H, CHIBA T, MEGURO K, et al. Fabrication and characterization of a ZnO X-ray sensor using a high-resistivity ZnO single crystal grown by the hydrothermal method[J]. Nuclear Inst and Methods in Physics Research, A, 2011, 665: 15-18.
[3] KASAP S, FREY J B, BELEV G, et al. Amorphous and polycrystalline photoconductors for direct conversion flat panel X-ray image sensors[J]. Sensors, 2011, 11(5): 5112-5157.
[4] WELLINGS J, CHAURE N, HEAVENS S, et al. Growth and characterisation of electrodeposited ZnO thin films[J]. Thin Solid Films, 2008, 516(12): 3893-3898.
[5] UNO K, TAUCHI Y, TANAKA I. ZnO thick film growth on n-GaN by photoassisted electrodeposition[J]. Japanese Journal of Applied Physics, 2013, 52(8): 08JE16.
[6] MAROTTI R E, GUERRA D N, BELLO C, et al. Bandgap energy tuning of electrochemically grown ZnO thin films by thickness and electrodeposition potential[J]. Solar Energy Materials & Solar Cells, 2004, 82(1-2):85-103.
[7] XU L F, GUO Y, LIAO Q, et al. Morphological control of ZnO nanostructures by electrodeposition[J]. The Journal of Physical Chemistry B, 2005, 109(28): 13519-13522.
[8] GHASEMPOUR ARDAKANI A, PAZOKI M, MAHDAVI S M, et al. Ultraviolet photodetectors based on ZnO sheets: the effect of sheet size on photoresponse properties[J]. Applied Surface Science, 2012, 258(14): 5405-5411.
[9] CHEN J L, CHEN D, ZHOU Y, et al. Electrochemical deposition of Al-doped ZnO transparent conducting nanowire arrays for thin-film solar cell electrodes[J]. Materials Letters, 2014, 117: 162-164.
[10] XIAO C, SUN S, LAI Q. Direct electrodeposition of ZnO nanosheets film on plastic substrate[J]. IOP Conference Series Materials Science and Engineering, 2020, 761(1): 012008.
[11] SIELMANN C, WALUS K, STOEBER B. Zinc exhaustion in ZnO electrodeposition[J]. Thin Solid Films, 2015, 592: 76-80.
[12] TAUC J, GRIGOROVICI R, VANCU A. Optical properties and electronic structure of amorphous germanium[J]. Physica Status Solidi (b), 1966, 15(2): 627-637.
[13] RAO T P, KUMAR M, ANGAYARKANNI S A, et al. Effect of stress on optical band gap of ZnO thin films with substrate temperature by spray pyrolysis[J]. Journal of Alloys & Compounds, 2009, 485(1-2): 413-417.
[14] BAGNALL D M, CHEN Y F, SHEN M Y, et al. Room temperature excitonic stimulated emission from zinc oxide epilayers grown by plasma-assisted MBE[J]. Journal of Crystal Growth, 1998, 184/185(1/2): 605-609.
[15] SELIM F A, WEBER M H, SOLODOVNIKOV D, et al. Nature of native defects in ZnO[J]. Physical Review Letters, 2007, 99(8): 085502.
[16] TON-THAT C, WESTON L, PHILLIPS M R. Characteristics of point defects in the green luminescence from Zn- and O-rich ZnO[J]. Physical Review B, 2012, 86(11): 115205.
[17] LV J, LI C. Evidences of V_O, V_Zn, and O_i defects as the green luminescence origins in ZnO[J]. Applied Physics Letters, 2013, 103(2013): 232114-1.
[18] CAGLAR Y, CAGLAR M, ILICAN S. XRD, SEM, XPS studies of Sb doped ZnO films and electrical properties of its based Schottky diodes[J]. Optik, 2018, 164: 424-432.
[19] ABDEL-WAHAB M, JILANI A, YAHIA I, et al. Enhanced the photocatalytic activity of Ni-doped ZnO thin films: morphological, optical and XPS analysis[J]. Superlattices and Microstructures, 2016, 94: 108-118.
[20] KABONGO G L, MHLONGO G H, MOTHUDI B M, et al. Structural, photoluminescence and XPS properties of Tm³⁺ ions in ZnO nanostructures[J]. Journal of Luminescence: An Interdisciplinary Journal of Research on Excited State Processes in Condensed Matter, 2017, 187: 141-153.
[21] LIAO Z M, LV Z K, ZHOU Y B, et al. The effect of adsorbates on the space-charge-limited current in single ZnO nanowires[J]. Nanotechnology, 2008, 19(33): 335204.