From evaluation to licencing of low-cost miniature conductivity temperature and dissolved oxygen sensor technology

测量水参数在许多行业和环境科学中是必需的。最广泛测量和需要的参数是温度、盐度和溶解氧。这些测量用于多种应用，如天气预报，气候建模，水质评估，污水处理和水产养殖。在许多情况下，需要高精度测量和连续数据。具有高性能的商业传感器已经提供了这些数据，并在这些领域取得了巨大的进步。然而，它们是昂贵的（约10000美元）和大的，防止在高密度数据收集系统中的广泛使用。有更小更便宜的传感器（500美元），但目前对许多应用来说不够准确或精确，南安普顿大学和国家海洋学中心开发了一种独特的超小型高精度盐度温度和溶解氧传感器，用于水分析。这些参数都是在一个小的玻璃芯片（8 × 10 mm）上测量的，该芯片具有图案化的金属轨道以形成传感器。盐度是根据与水接触的四个微电极测量的温度和电导率的组合来计算的。这个芯片被插入到定制的电子设备中，这些电子设备操作芯片，存储数据并与外界通信。整个传感器系统的大小相当于一支记号笔。该技术具有巨大的市场潜力（按2011年费率计算，估计为4.2亿美元），并获得了巨大的商业利益。然而，目前商业化的障碍是长期稳定性的技术问题。这在三个月内仅为0.016 C，但许多应用在三个月内仅需要0.001 C的稳定性。我们已经确定，问题的根源是吸水，这导致我们用于包装和绝缘金属轨道的聚合物的溶胀（1.6体积%）。这种膨胀导致芯片和金属轨道传感器随着时间的推移而弯曲或伸长，从而导致漂移。这会影响温度和电导率的测量，从而影响盐度的准确性。解决方案是用坚硬的防水材料（如氧化硅）代替聚合物绝缘体。氧化硅广泛用于电子领域，其中沉积了非常薄的层（100 nm，万分之一毫米）。在我们的芯片中，我们需要更厚的层> 0.01 mm。挑战在于开发制造这些厚层和新传感器芯片的工艺。一旦解决了这个技术问题，我们将进行短期和长期测试，以验证市场和应用的足够性能。我们将与传感器公司合作，我们希望与他们合作将产品推向市场。该项目的成果应该是与一家公司和一条新的产品线达成许可协议。

Measuring water parameters is required in many industries and in environmental science. The most widely measured and required parameters are temperature, salinity and dissolved oxygen. These measurements are used in multiple applications such as weather forcasting, climate modelling, water quality assessment, sewage processing and aquaculture. In many cases a high precision measurement and continuous data is required. Commercial sensors with high performance have delivered this data and have enabled dramatic advances in these fields. However, they are expensive (~$10000) and large preventing widespread use in high density data collection systems. Smaller and cheaper ($500) sensors are available, but currently are not sufficiently accurate or precise for many applications.The University of Southampton and the National Oceanography Centre have developed a unique ultra miniature high-precision salinity temperature and dissolved oxygen sensor for water analysis. These parameters are all measured on a small glass chip (8 x 10 mm) with patterned metal tracks to form the sensors. Salinity is calculated from a combination of temperature and conductivity measured with four micro electrodes in contact with the water. This chip is plugged into custom made electronics that operates the chip and stores the data and communicates with the outside world. The total sensor system is the size of a marker pen. The technology has significant market potential (estimated $420M at 2011 rates) and has received significant commercial interest. However, the current barrier to commercialisation is a technical problem with long term stability. This is only 0.016 C in three months, but many applications require only 0.001 C stability over 3 months.We have identified that the source of the problem as water uptake which causes swelling (1.6% by volume) of the polymer that we use to package and insulate the metal tracks. This swelling causes the chip and metal track sensors to bend or elongate over time causing the drift. This affects the temperature and conductivity measurement and hence the salinity accuracy.The solution is to replace the polymer insulator with a hard and water resistant material such as Silicon Oxide. Silicon oxide is widely used in electronics where very thin (100 nm, one ten thousandth of a millimetre) layers are deposited. In our chip we require a much thicker layer > 0.01 mm. The challenge is to develop a process to manufacture these thick layers and new sensor chips.Once this technical problem is resolved, we will conduct short and long term testing to verify sufficient performance for the markets and applications. We will do this in partnership with sensor companies who we hope to work with to bring the product to market. The outcome of the project should be a license agreement with a company and a new product line.