I-Corps: Ultra-low Power Chemical Vapor Nano-sensor

在许多领域，空气质量或气体成分可以提高生活质量和安全。这些领域包括健康和安全(如在采矿过程中检测到甲烷)、医疗(呼吸诊断)、执法(如检测非法药物)和车辆安全(如检查酒精和药物以确保安全驾驶)。目前的技术满足了一些需求，但昂贵、笨重和耗电。该项目提出了一种微型、超低功耗、灵敏的微桥热导型气体传感器，该传感器的功率低于50微瓦。此外，该传感器的重复性和稳定性都很好，在故障前可以进行超过300亿次的测量。提出的传感器的主要优势是其超低功耗，并且不需要在现场重新校准。这大大节省了成本，因为大多数化学传感器需要在给定的时间间隔进行校准，并且电池功率需要频繁变化。由于传感器是电导式的，所以测量仪器非常简单。该团队已经研究了通过脉冲操作来最小化噪声和提高数据稳定性的方法。该团队还研究了瞬时测量，其响应时间被记录为气体成分的函数。

There are numerous areas where air quality or gas composition can enhance the quality of life and safety. These areas include health and safety (such as detection of methane during mining), medical (breath diagnosis), law enforcement (such as detection of illicit drugs), and vehicle safety (such as checking for alcohol and drugs for safe driving). Current technology meets some of the needs but is expensive, bulky and power hungry. This project proposes a miniature, ultra-low power, sensitive, microbridge thermal conductivity based gas sensor that uses less than 50 microwatts of power. In addition, the reproducibility and stability of the sensor are excellent achieving over 30 billion measurements before failure.The key advantages of the proposed sensors are their ultra-low power consumption and the lack of need for recalibration in the field. This results in substantial cost savings since most chemical sensors require calibrations at given time intervals as well as frequent changes in the battery power. As the sensor is conductimetric, the instrumentation for measurement is very straight forward. The team has investigated methods for minimizing noise and improving stability of the data with pulsed operation. The team has also investigated transient measurements for which the response time is recorded as a function of the gas composition.