California Institute of Technology

City of Hope

City of Hope National Medical Center and Beckman Research Institute

Xuan-Qi Wang

Yu-Chong Tai

Charles I Grosjean

Xing Yang

Amish Desai

Terry D Lee

Lawrence Licklider

Fukang Jiang

Ellis Fan-chuin Meng

Zhigang Han

A MEMS device with an overhanging 'polymer' capillary provides vital and significant improvements in interfacing a MEMS electrospray nozzle to an MS inlet or other macroscopic instrumentation. The fabrication methodology associated therewith is easily expanded to include built-in micro particle filters and centimeter long serpentine micro channels provided on-chip and fabricated using a low temperature process.

Polymer based electrospray nozzle for mass spectrometry

The present disclosure describes a Parylene micro check valve including a micromachined silicon valve seat with a roughened top surface to which a membrane cap is anchored by twist-up tethers. The micro check valve is found to exhibit low cracking pressure, high reverse pressure, low reverse flow leakage, and negligible membrane-induced flow resistance when used as a valve over a micro orifice through which flow liquid and gas fluids.

Parylene micro check valve and fabrication method thereof

A micromachined fluid handling device having improved properties. The valve is made of reinforced parylene. A heater heats a fluid to expand the fluid. The heater is formed on unsupported silicon nitride to reduce the power. The device can be used to form a valve or a pump. Another embodiment forms a composite silicone/parylene membrane. Another feature uses a valve seat that has concentric grooves for better sealing operation.

Micromachined parylene membrane valve and pump

A combined IC/Mems process forms the IC parts first, and then forms the MEMS parts. One option forms a parylene overlayer, then forms a cavity under the parylene overlayer.

IC-compatible parylene MEMS technology and its application in integrated sensors

In an embodiment, a check valve assembly may include an in-channel check valve connected between the front and rear portions of a channel attached to a silicon substrate. The channel may have a width between about 10 &mgr;m and about 400 &mgr;m, and the check valve may have a width between about 50 &mgr;m and about 500 &mgr;m. The check valve may be generally circular in shape. The check valve may also be normally closed, that is, sealed in the absence of a pressure differential between the front and rear portions of the channel. The check valve may include a sealing cap that contacts a valve seat to seal the valve. The sealing cap and the valve seat may each be formed from Parylene C membranes that are about 1 &mgr;m to about 5 &mgr;m thick. The valve seat may include a metal layer to separate the contacting surfaces of the valve seat and the sealing cap in the closed position. The check valve may open for forward pressures that match or exceed a threshold pressure and remain closed for forward pressures below the threshold pressure and reverse pressures.

Normally closed in-channel micro check valve

A silicone rubber diaphragm pump utilizing a pair of MEMS Parylene check valves and a miniature solenoid plunger and actuator is comprised of a spacer sandwiched by a silicone rubber diaphragm on one side and a check valve support on the other. The check valves in the check valve support form the inlet and outlet to a pumping chamber defined between the check valve support and silicone rubber diaphragm. The pumping action has been demonstrated by driving the silicone diaphragm with the plunger using the solenoid type actuator to generate over and under pressures in the chamber. This forces the pumped medium into and out of the chamber, thus allowing the medium to be transported. Tubing or connectors affixed to the inlet and outlet ports of the check valve support structure allow for external fluidic access. The pump works with both gas and liquid.

Growing community of inventors

Los Angeles, CA, United States of America

Xuan-Qi Wang