High sensitive and rapid responsive n-type Si: Au sensor for monitoring breath rate

125 μm-breath sensor with high sensitivity and rapid response was prepared by using n-type Si: Au material. Its sensitivity coefficient and time constant were 4 V.sec / L and 38 msec, respec-tively. Its working principle was based on ano- malous resistance effect, which not only increa- sed the sensitivity, but also reduced its time con-stant greatly. Its signal processing system can select the breath signals and work stably. Therefore, the small changes of breath system can be measured and, especially, patient’s breath rate can be monitored at a distance.