A silicon-on-insulator based micro check valve

In this paper we present a bulk micromachined check valve with very high frequency and extremely low leak rates. The valve is designed to have a hexagonal orifice, a hexagonal membrane flap and three flexible tethers. The three elbow-shaped flexible tethers are used to secure the membrane flap to the valve seat and to obtain large flap displacement in the forward flow direction. A silicon-on-insulator wafer and deep reactive ion etching technology are used to implement this microvalve. A very simple fabrication process has been developed, and only two photolithographic masks are required. Preliminary fluidics testing on a 1.44 mm size check valve was performed. A maximum flow rate (deionized water) of 35.6 ml min−1 was obtained at a forward pressure of 65.5 kPa, and only negligible leakage rate was observed at a reverse pressure of up to 600 kPa. The frequency response of the valve in air was also measured and its first resonance frequency was found at 17.7 kHz.

在本文中，我们介绍了一种具有极高频率和极低泄漏率的体微机械加工止回阀。该阀门设计有一个六边形孔口、一个六边形膜瓣和三个柔性系绳。这三个肘形柔性系绳用于将膜瓣固定在阀座上，并在正向流动方向上获得较大的瓣位移。采用绝缘体上硅晶片和深反应离子刻蚀技术来制造这种微阀。已经开发出一种非常简单的制造工艺，且仅需两个光刻掩模。对一个尺寸为1.44毫米的止回阀进行了初步的流体测试。在正向压力为65.5千帕时，获得了35.6毫升/分钟的最大流量（去离子水），并且在高达600千帕的反向压力下仅观察到可忽略不计的泄漏率。还测量了该阀门在空气中的频率响应，发现其第一共振频率为17.7千赫兹。