用于AMOLED 的非晶氧化物薄膜晶体管稳定性的研究

项目名称： 用于AMOLED 的非晶氧化物薄膜晶体管稳定性的研究

项目编号： No.61274082

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 无线电电子学、电信技术

项目作者： 张志林

作者单位： 上海大学

项目金额： 100万元

中文摘要： AM-OLED是平板显示未来的主流,TFT基板是核心。氧化物TFT由于它低成本绿色等优势是即将取代现有的TFT背板技术。而其稳定性是目前阻碍其应用的关键。本项目以氧化物TFT的稳定性为重点。研究正负偏压不稳定性，偏压光照不稳定性，特别是负偏压光照不稳定性等现象，通过各种物理测试、分析其机理及提高稳定性的对策。1) 对于有源层：添加IV族元素减少氧空位减少带间能级及探索新结构和组分的有源层 2）采用ALD等方法研制Al2O3等高介电常数，高绝缘强度绝缘层3）有源层与-绝缘层的界面：用C-V 方法研究其界面，通过加入薄的缓冲层以及各种界面处理来，减少界面缺陷，改善界面。4）封装：对底栅结构，使用etching stopper 及抗水抗氧的钝化层对有源层进行全封闭。研制顶栅结构，有利稳定性。最终研制出性能稳定的有实用价值的2-3英寸单色氧化物TFT-OLED显示屏及其关键工艺。

中文关键词： 原子层沉积；溶液法生长氧化物有源层；氮负离子掺杂；带内能级态密度；负偏压光照稳定性

英文摘要： AM-OLED is the mainstream of flat panel display. The thin film transistor (TFT) backplane is the core of AM-OLED. Oxide TFT is a promise backplane for OLED Due to its better performances, lower cost, green process. In this project, we put the emphases on the stability of Oxide TFT. The device stability is sensitive to bias/current stress, temperature, light illuminating, and water vapor exposure. We will study Bias voltage stress induced instability (the shift of threshold voltage) without light illumination or under light illumination, especially, Negative Bias- light illumination instability: Investigate the dependences of the shift of threshold voltage on the stress time, stress temperature, intensity and wavelength of light illumination , further analyze the mechanism for the instability and adopt the corresponding measures to improve the stability. 1) For channel layer, to incorporate tetravalent elements (Hf4+, Cr4+, Si4+) ,which have high metal-oxygen bonding-strength, into the IZO system can strongly bond with oxygen, resulting in the reduction of oxygen vacancy, which acts as the subgap hole traps, leading to improvement of stability. 2) Fabricate the high K insulator layer with high insulation strength by using Atomic Layer Deposition (ALD) method, such as Al2O3, instead of PECVD. ALD method is parti

英文关键词： atomic layer deposition (ALD)；Combustion solution process；Nitrogen anion doping；Sub-gap density of states；Negative bias illumination stress(NBIS)