高浓度掺杂非晶铟镓锌氧化物薄膜的态密度模型研究
Study on Density of States Model of High-Concentration Doped Amorphous Indium Gallium Zinc Oxide Thin-Film
蔡坤林 1谢应涛 1蹇欢 1黄雁琳 1翁嘉明2
作者信息
- 1. 重庆邮电大学电子工程系,重庆 400065
- 2. 上海交通大学电气工程系,上海 200240
- 折叠
摘要
针对背沟道刻蚀(Back Channel Etch,BCE)技术的非晶铟镓锌氧化物(a-IGZO)薄膜晶体管(Thin Film Transistor,TFTs),建立了一种高浓度掺杂态密度模型(High Concentration Doping Density Of States model,HCD-DOS model),并通过数值模拟研究态密度关键参数对器件性能的影响,以此揭示a-IGZO TFTs中制备工艺对导电沟道修复的物理机理.首先,采用结合强度较高的钼/铜双层结构作为栅/源/漏电极,引入BCE方法制备了底栅顶接触(Bottom-Gate Top-Contact,BG-TC)TFTs.其次,建立了适用于BCE技术的a-IGZO TFTs的HCD-DOS模型.随后,基于TCAD(Technology Computer Aided Design)仿真器对态密度关键参数进行数值研究,结果表明,不同态密度参数对a-IGZO TFTs器件转移特性曲线、电学特性以及沟道内部电子浓度分布的影响有所差异.最后,基于HCD-DOS模型探索SiOx钝化层沉积和N2O等离子体处理对器件内部机理的影响.研究发现,N2O等离子体处理对态密度分布和沟道载流子浓度有显著影响,进而导致阈值电压正向漂移.
Abstract
A high-concentration doped density of states model(HCD-DOS model)was established for amorphous in-dium gallium zinc oxide(a-IGZO)thin-film transistors(TFTs)with back-channel etch(BCE)technology.The effect of the key parameters of the density of states on the device performance was also investigated by numerical simulation to reveal the physical mechanism of the preparation process to repair the conductive channel in a-IGZO TFTs.Firstly,the molybde-num/copper bilayer structure with high bonding strength was used as gate/source/drain electrodes,and the bottom-gate top-contact(BG-TC)TFTs was prepared by introducing the BCE method.Secondly,the HCD-DOS model of a-IGZO TFTs suitable for BCE technology was developed.Subsequently,the key parameters of the density of states were investigated nu-merically based on the TCAD(Technology Computer Aided Design)simulator.The results demonstrated that different den-sity of states parameters had different effects on the transfer characteristic curves,electrical characteristics,and electron con-centration distribution inside the channel of the a-IGZO TFTs device.At last,the influence of SiOx passivation-layer deposi-tion and N2O plasma treatment on the internal mechanism of the device was explored based on the HCD-DOS model.It was found that N2O plasma treatment had a significant effect on the density of states distribution and channel carrier concen-tration,which in turn caused the threshold voltage to drift.
关键词
非晶铟镓锌氧化物薄膜晶体管/态密度模型/钝化层沉积/等离子体处理/背沟道刻蚀Key words
amorphous indium gallium zinc oxide thin-film transistors/density of states model/passivation-layer de-position/plasma treatment/back-channel etch引用本文复制引用
基金项目
国家自然科学基金(61804019)
重庆市教委科学技术研究项目(KJZD-K202200607)
重庆市研究生科研创新项目(CYS22441)
出版年
2024
国家科技期刊平台
NSTL
万方数据