SGER: An Investigation of Silicon Germanium Terahertz Sources

用分子束外延技术在硅衬底上生长掺硼和掺镓的硅和锗硅薄膜。器件结构将使用光刻结合反应离子刻蚀和金属蒸发来制造。它们的电致发光性能将作为掺杂剂类型和浓度的函数来确定。将使用电气和光学设备建模来帮助解释观测结果。电致发光测量将安装在工作在太赫兹范围内的傅里叶变换红外光谱仪的低温恒温器中的电接触设备上。特别是，发射强度和光谱将根据施加的电流和温度来确定。基于这一结果，我们将从掺杂腔谐振腔的辐射增益和损耗来评估设计基于掺杂跃迁的太赫兹激光器的可能性。由于掺杂态的激发机制和辐射效率尚不清楚，因此建议的研究应该被认为是探索性的和高风险的，并将在本项目中进行探索。这项研究的潜在影响涉及到一种结构简单、与硅集成电路兼容的太赫兹发射设备，具有潜在的低成本和广泛的用途。与计算机芯片集成的紧凑型太赫兹发射器将在以下领域有应用：化学和生物传感、医疗诊断和高带宽通信。SGER赠款将是支持这项工作的适当手段，因为结果将表明是否有理由进行更多的研究，并可用于争取更多的资金。将结合这些研究活动开展教育和外联活动。这些措施将包括研究生参与研究，将研究成果纳入教学，以及继续发展一系列本地学校外展活动。将设计一个适合高中生或大学一年级学生的互动网站(http://www.ece.udel.edu/~kolodzey/terahertztools/terahertztools.htm)，该网站将说明太赫兹频率的特性，并允许学生探索太赫兹吸收和反射现象。

Layers of boron doped and gallium doped Si and SiGe will be grown by molecular beam epitaxy on Si substrates. Device structures will be fabricated using photolithography combined with reactive ion etching and metal evaporation. Their electroluminescent properties will be determined as a function of dopant type and concentration. Electrical and optical device modeling will be used to help interpret the observations. Electroluminescence measurements will be made on electrically contacted devices mounted in a cryostat in a Fourier Transform Infrared Spectrometer that operates in the THz range. In particular, the emission intensity and spectrum will be determined versus the applied current and temperature. Based on the results, the possibility of designing a TeraHertz laser based on dopant transitions will be assessed in terms of the radiative gain and losses from doped cavity resonators.The proposed research should be considered exploratory and high risk because the excitation mechanism of the dopant states and their radiative efficiency is not well understood, and will be explored during this project. The potential impact of this research concerns a TeraHertz emitting device with a simple structure that is compatible with Si integrated circuitry for potential low cost and widespread use. Compact TeraHertz emitters that are integrated with computer chips would have applications in: chemical and biological sensing; medical diagnostics, and high bandwidth communications. An SGER grant would be a suitable means of supporting the work because the results would indicate whether additional research is justified, and may be used to solicit additional funding.Education and outreach activities will be carried out in combination with these research activities. These will include the participation in research of a graduate student, the incorporation of research findings into teaching, and the continued development of a series of local school outreach activities. An interactive web site (http://www.ece.udel.edu/~kolodzey/terahertztools/terahertztools.htm) will be designed suitable for senior high school or freshman college students, which will illustrate the properties of the TeraHertz frequencies, and allow students to explore terahertz absorption and reflectivity phenomena.