高性能增强型Si基ZnO单晶薄膜晶体管的制备与研究

项目名称： 高性能增强型Si基ZnO单晶薄膜晶体管的制备与研究

项目编号： No.61306011

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 无线电电子学、电信技术

项目作者： 梁会力

作者单位： 中国科学院物理研究所

项目金额： 25万元

中文摘要： 作为迅猛发展的透明电子学器件系统的一个核心元器件，ZnO基薄膜晶体管（TFT）具有迁移率高、对可见光透明、电学性能可调范围大、光敏退化性小等优点，具有广阔的应用前景。目前ZnO基TFT的研究主要存在以下问题：沟道层通常为多晶，迁移率无法进一步提升，工作模式为耗尽型，功耗高；非晶InGaZnO的In和Ga储量十分有限、价格非常昂贵，只能作为过渡阶段产品使用。针对这些现状，本项目拟利用独创的界面控制技术，通过分子束外延法在硅衬底上制备高质量的ZnO单晶薄膜作为n型沟道，研究生长温度及薄膜厚度对载流子浓度的影响，获得沟道层的可控制备工艺；研究MgO、BeO及MgZnO等外延薄膜的介电性能，重点研究ZnO沟道和上述绝缘层的界面特性，获得降低界面缺陷密度的方法。进一步通过优化TFT器件结构以及改善欧姆接触，大幅提高器件迁移率、开关比，从而在低能耗增强型ZnO基TFT的研制中获得重大进展。

中文关键词： 薄膜晶体管；界面工程；分子束外延；氧化锌；硅

英文摘要： ZnO thin film transistor (TFT), with the advantages of high field mobility, insensitivity with the visible light and controllable electrical properties, is considered as a core cell in the fast developing transparent electronic systems, which could be applied in a variety of areas. So far, most of the research on ZnO TFT is mainly focusing on poly-crystal ZnO with a low field mobility due to the carriers scattering from the grain boundaries. Besides, the concentration of the background carriers in poly-crystal ZnO is usually very high, resulting in a depletion TFT mode where a gate voltage is necessary to cut off the circuit. Moreover, although IGZO-TFT can improve the device performance, the reserve of In and Ga on the earth is very limited, making it urgent to find out an appropriate new material to replace IGZO. Therefore, in this project, high-quality single-crystal ZnO thin film with high carrier mobility is proposed to substitute IGZO as an active layer in the TFT device structure. In order to combine with the mature Si micro-electronic industry, single-crystal ZnO thin film will be deposited on the Si substrate by the unique interfacial engineered molecular beam epitaxial technique. The influence of the growth temperature and film thickness on the carriers will be investigated in order to find out a repro

英文关键词： thin film transistor；interface engineering；molecular beam epitaxy；ZnO；Si