Plasma Oxidation/Anodization of Silicon Films for Photovoltaic and Flat Panel Display Applications

用于光伏和平板显示应用的硅薄膜的等离子体氧化/阳极氧化

• 批准号: 9214138
• 负责人: Dennis Hess
• 金额: $ 23.7万
• 依托单位: Lehigh University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-10-15 至 1996-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9214138&HistoricalAwards=false
• 关键词: Plasma; Oxidation; Anodization; Silicon; Films

Research on electronic devices fabricated in thin films of amorphous silicon (a-Si) or polycrystalline silicon (p-Si) has recently gained momentum due to a variety of new applications for these devices. For example, the efficiency of experimental solar cells produced using a-Si films currently exceeds 12%. These efficiencies make such devices attractive for the realization of large area, low cost photovoltaic energy conversion systems. Another example is a-Si and p-Si thin film transistors (TFTs) which have made possible the fabrication of full color, flat panel displays. Such displays can be used in laptop computers and in future high definition TV. In addition to flat panel displays, TFTs fabricated in a- Si or p-Si can be used as switching elements in other large area electronic systems such as lenseless contact-type image sensors and position sensitive detectors. All of these devices (flat panel displays, image sensors and position sensitive detectors) are fabricated on low cost glass substrates; therefore the manufacturing temperatures must be kept below 600 C to avoid glass distortion. In the case of hydrogenated a-Si devices, the process temperatures should be below 450 C to avoid deterioration of the electronic properties of the a-Si. Oxidation of single crystal silicon (c-Si) has been used in the successful development and manufacture of integrated circuits. The importance of silicon oxidation is that thermal oxidation of silicon results in the growth of a high quality insulator and passivation layer with an interface to silicon that has relatively few surface traps which alter device properties and affect device stability. Oxidation temperatures used in the production of silicon integrated circuits is in the range of 800 to 1100 C. An alternative method will be tested in this research, the plasma oxidation or anodization process, in which the grown film is exposed to reactive ions, electron, atomic oxygen, and ultra violet (UV) photons during oxidation. This exposure leads to enhancement of the oxidation rates at low temperatures. Electron cyclotron resonance (ECR) plasmas will be used to oxidize or anodize a-Si and p-Si films. The oxidation kinetics of these processes will be studied as functions of the substrate temperature and plasma process conditions. Electronic devices will be fabricated and their characteristics correlated with growth conditions. This technology could impact the manufacture of low cost, high reliability, flat panel displays and solar cells.***//

非晶硅(a-Si)或多晶硅(p-Si)薄膜电子器件的研究最近由于这些器件的各种新应用而获得了发展势头。例如，使用a-Si薄膜生产的实验太阳能电池的效率目前超过12%。这些效率使这种器件在实现大面积、低成本的光伏能源转换系统方面具有吸引力。另一个例子是a-Si和p-Si薄膜晶体管(TFT)，它们使得制造全彩色平板显示器成为可能。这种显示器可以用于笔记本电脑和未来的高清晰度电视。除了平板显示器，a-Si或p-Si制造的TFT还可以用作其他大面积电子系统的开关元件，如无透镜接触式图像传感器和位置灵敏探测器。所有这些器件(平板显示器、图像传感器和位置灵敏探测器)都是在低成本玻璃基板上制造的；因此，制造温度必须保持在600℃以下，以避免玻璃变形。在氢化a-Si器件的情况下，工艺温度应低于450℃，以避免a-Si的电子性能恶化。单晶硅(c-Si)氧化已成功地应用于集成电路的开发和制造。硅氧化的重要性在于，硅的热氧化导致高质量绝缘层和钝化层的生长，其与硅的界面具有相对较少的表面陷阱，这些表面陷阱改变了器件的特性并影响了器件的稳定性。用于生产硅集成电路的氧化温度在800到1100摄氏度的范围内。在这项研究中将测试另一种方法，等离子体氧化或阳极氧化工艺，在该工艺中生长的薄膜暴露在反应离子，电子，原子氧，以及氧化过程中的紫外线(UV)光子。这种暴露导致了低温下氧化速率的提高。电子回旋共振(ECR)等离子体将用于a-Si和p-Si薄膜的氧化或阳极氧化。这些过程的氧化动力学将作为衬底温度和等离子体工艺条件的函数进行研究。电子器件将被制造出来，其特性与生长条件相关。这项技术可能会影响低成本、高可靠性、平板显示器和太阳能电池的制造。