SBIR Phase I: Fabrication of low-bandgap nano-crystalline SiGeC thin films using the Plasma Enhanced Chemical Vapor Deposition (PECVD) technique

这个小型企业创新研究(SBIR)第一阶段项目将开发光学带隙(Eg)在1.6-1.8 eV范围内的纳米晶Sigec薄膜，并增强吸收特性，从而实现低成本、高效率(20%)的光伏器件。以前提高光伏效率的尝试并不是始终如一和成功的。该方法使用等离子体增强化学气相沉积(PECVD)技术来沉积这些薄膜，通过能够操纵等离子体和电子温度来控制等离子体中的离子密度，并独立控制工艺参数，从而允许更好地控制工艺。这种灵活性在当前使用的技术中不存在。利用所提出的技术，可以在中等温度下在所需的衬底上沉积稳定一致的SiGEC薄膜。如果开发成功，这项技术可以为替代能源市场提供更高效率的太阳能电池。只有在能够证明基本工艺的情况下，才能实现薄膜的高度稳定、高沉积效率和工艺可伸缩性的大规模制造的目标。这项研究的更广泛的影响将在用于发电的低成本光伏(PV)器件上。如果成功完成，这项研究可能会在太阳能电池制造商和设备制造商之间建立强有力的合作伙伴关系，从而带来一个潜在的有利可图的光伏市场。目前，使用现有光伏设备产生的电力比传统电力贵3-4倍。选择的材料(硅、锗和碳)丰富，可以显著降低原材料成本。竞争激烈的市场对太阳能发电的需求已经有了大量的基础知识，这使得开发具有现实性能目标的过程很容易实现。实现这一目标的主要挑战在于能够控制沉积过程以确保稳定和稳健的过程，因为以前的工作未能取得一致的结果。生产三结薄膜太阳能电池的最初目标是值得进行的第一次产品演示，这将证明拟议技术的有效性，并轻松地吸引第三方资金。

This Small Business Innovation Research (SBIR) Phase I project will develop nanocrystalline SiGeC thin films with an optical bandgap (Eg) in the range of 1.6-1.8 eV, and enhanced absorption characteristics, leading to low-cost, high-efficiency (20%) photovoltaic devices. Previous attempts at improving the photovoltaic efficiency have not been consistent and successful. The proposed approach uses plasma-enhanced chemical vapor deposition (PECVD) technique to deposit these films, which allows greater control of the process by being able to manipulate the plasma and electron temperatures to control the ion density in the plasma, with an independent control of the process parameters. This flexibility does not exist in the currently used techniques. With the proposed technique, stable and consistent films of SiGeC can be deposited on the desired substrate at moderate temperatures. If successfully developed, this technique could provide higher efficiency solar cells for the alternative energy market. The goal of highly stable films, high deposition efficiency and process scalability for large-scale manufacturing can only be achieved if the basic process can be proven.The broader impacts of this research will be in the low-cost photovoltaic (PV) devices for power generation market. If successfully completed, this research could lead to a strong partnership between solar cell manufacturers and equipment manufacturers, leading to a potentially lucrative photovoltaics market. Currently, electricity generated with available PV devices is 3-4 times more expensive as the conventional electricity. The selected materials (Si, Ge and C) for the thin film are abundantly available, which can significantly reduce the raw materials costs. A large body of basic knowledge of the requirements of solar electricity for the competitive market already exists, which makes the development of the process with a realistic performance target easy to achieve. The main challenge for achieving this goal lies in being able to control the deposition process to assure a stable and robust process, as the previous work has not been able to achieve consistent results. The initial target of producing a triple-junction thin-film solar cell is a worthy first product demonstration, which will prove the efficacy of the proposed technique, and attract third-party funding with little difficulty.