Nanostructured absorption and emission layers for thermal infrared detectors and emitters

具有高探测率的快速热红外探测器必须表现出对环境足够高的绝热性以及低热质量（热容）。可以制造厚度小于1 μm的非常薄的检测器元件。然而，需要吸收层或堆叠层系统来确保高吸收率，这导致具有不利的高热容和差的热传导的厚层。初步测试表明，用掠射角沉积（GLAD）制造的非常薄的层在空气和敏感材料之间提供了良好的折射率匹配，因此，联合收割机结合了高吸收率和非常低的层厚度。该层的性质可以特别地受到沉积角度的变化的影响，从而允许制造具有高和宽带吸收行为的层。同时，这些吸收层可以用作热释电传感器中的电极。所有这些关系都应进行建模和实验研究，并应导致设计指南，可用于从给定的技术要求中推导出GLAD技术的工艺参数。然而，它必须在非常高的温度下保持稳定，因为辐射功率会随着工作温度的增加而增加。因此，应在项目的第二部分中对高温材料的GLAD技术和硅技术的集成进行调查。这种具有非常低的热容量的超薄辐射加热器比现有技术的加热器更有效，即具有更低的电功率消耗，并且可以在更高的频率下操作。这将为许多应用带来巨大的优势，并将在演示器上得到证明。

Fast thermal infrared detectors with high detectivity must show a sufficiently high thermal insulation to ambient as well as a low thermal mass (heat capacity). It is possible to manufacture very thin detector elements having a thickness of less than 1 µm. However, absorption layers or stacked layer systems are required to ensure high absorptivity, which leads to thick layers with disadvantageous high heat capacities and poor heat conduction. Preliminary tests showed that very thin layers manufactured with glancing angle deposition (GLAD) provide a good refractive index matching between air and sensitive material and, therefore, combine a high absorptivity with a very low layer thickness. The properties of the layer can be specifically influenced by variation of the deposition angle allowing the manufacturing of layers with high and broadband absorption behavior. At the same time these absorption layers can be used as electrodes in pyroelectric sensors. All those relationships should be modelled and experimentally investigated and should lead to design guidelines, which can be used to derive process parameters of the GLAD-technology from given technical requirements.The layers described above can also be used as thermal emitters. However, it has to be stable at very high temperatures, because the radiated power increases with operating temperature. Therefore, an investigation of the GLAD-technology for high-temperature materials and integration in silicon technology should be carried out in the second part of the project. Such ultra-thin radiant heaters with very low heat capacity are more efficient, i.e. have a lower electrical power consumption, than state of the art heaters and can be operated at higher frequencies. This would lead to tremendous advantages for many applications and is to be proven on demonstrators.