Principal investigator: Mr. Chen Mei Ma
Co-investigator: A/Prof Thomas Gong Haiqing
Date started: 07/1998
To design and develop a Micro Liquid Delivery System for medical use.
Deflection caused by mismatch of thermal expansion of two layers of materials.
Structure of Micro LDS
The Micro LDS consists of four major subsystems:
- A bimetallic composite membrane microactuator.
- Two micro check valves
- Four micro flow rate sensors integrated in the bimetallic composite membrane.
- An electrically isolated meander type resistor (sandwiched in bimetallic membrane)
Working Principle (one cycle of pumping)
The working of Micro LDS includes two steps:
- the bimetallic thin film is heated, an upward deflection of the membrane occurs, negative pressure generates inside the chamber. Thus inlet valve opens, fluid flows in the chamber.
- the bimetallic thin film is cooled, it bends down, positive pressure generates. Outlet valve opens and fluid flows out.
- Small size
- Low power consumption
- IC compatible fabrication process
- Low leakage