Integrated Virtual Impactor Enabled PM 2.5 Sensor

As more and more proofs show that fine particles (diameter of $2.5~\mu \text{m}$ and below) pose more risk on human health than coarse particles, an increasing need for monitoring fine particles has emerged. A miniaturized sensor designed for measuring fine particle concentration is presented in this paper. The proposed sensor possesses a compact size of only 15 mm $\times10$ mm $\times1$ mm. A virtual impactor has been integrated as a particle size selector and the design is optimized by simulation-assisted analysis. The sensor is realized by silicon microfabrication and wafer-level packaging. Testing results show that a high measurement accuracy of $2.55~\mu \text{g}/\text{m}^{3}$ has been achieved.