Project: MicroPumps for ink-jet, electronics cooling, lab-on-chip and bio-medical technologies

OBJECTIVE_x000D__x000D_Modular array micro-pumps for ink-jet, electronics cooling, lab on chip and bio-medical technologies._x000D__x000D__x000D_BACKGROUND_x000D__x000D_In recent years there has been growing interest in the development of so-called micro-pumps. Laser and Santiago in 2003 published “A review of micro-pumps” that reCOs a useful overview of the state of the art and suggested a system of classification for micro-pumps._x000D_The field of conventional, macroscopic pumps consists mostly of piston pumps, rotary vane pumps and peristaltic pumps. For reasons of scale, material properties and available manufacturing processes, none of these approaches has yet been successfully used in micro-pumps._x000D_Macroscopic displacement pumps have slow speeds of response, due to the inertia of the motors and spindles driving the piston or diaphragm. In applications where demand can fluctuate rapidly, for instance in inkjet ink supplies, this leads to the need for additional apparatus to control pressure, leading to extra complexity and costs and lower system functionality and reliability. Pumps of this size are too big and heavy for some of the intended applications, for instance cooling of electronics in mobile applications and computers. In addition, the swept and priming volumes of such pumps are quite large, so that for applications where only a small volume of fluid is available or affordable, such pumps are quite unsuitable._x000D_Micro-pumps have been largely built around reciprocating diaphragms, fabricated from elastic membranes, often made of silicon, with piezo-electric actuation. The required non-return valves have usually been based either on flexible flaps or fixed geometries such as nozzle-diffuser devices. Such micro-pumps are reported as being capable of only very limited rates of flow. For instance, in Laser and Santiago’s review, the highest reported flow rate of 16 millilitres per minute. In addition, these pumps generate high levels of pressure and flow rate fluctuations. Finally, they generally do not have the ability to produce high pressures._x000D_Thus there exists a number of unfulfilled requirements that would be met by small, agile pumps that deliver well-controlled flows in response to the needs of the applications._x000D__x000D_GOALS OF THE PROJECT_x000D_Delivery of a working demonstrator micro-pump with the following attributes:_x000D_Compact; affordable; modular; excellent pressure and flow rate control; low internal volume_x000D__x000D_TECHNOLOGY AND MARKET APPLICATION_x000D_The proposed micro-pump is based on two well-established technologies, micro-fluidics and piezo-electric inkjet. The project Ps have well-established experience in both areas. Thus many of the technical risks that would otherwise be significant can be better managed. The novelty and utility of the application lies in the ways that these two technologies are brought together and exploited._x000D_The resulting device will be modular in design and construction, allowing each device to be well-matched to whatever application it is aimed at. The architecture of the device will consist of layers of micro-machined wafers aligned accurately to one another and bonded together. The fluids to be handled will pass through systems of channels etched or cut into the surfaces of the wafers, then though series of holes or nozzles micro-machined into the surfaces of the wafers, into further channels in the next wafer. Each layer of channels would perform a specific function such as applying pressure or rectifying the flow._x000D_Each pump will, in principle, set new standards for control of pressure and flow rate, qualities that are demanded by several of the target applications. _x000D__x000D_PROJECT PS/EXPERTISE_x000D_The technology employed for the micro-pump comes from two different, but well-established areas; those of silicon MEMS and ink-jet printing. Lionix is well-established in the former, whilst AtomJet has great experience in the latter._x000D_LioniX bv: Fabrication technology to realize micropumps in MST technology. In particular, the fabrication of the pump's fluidic structures and miniature internal nozzles by deep reactive ion etching and other MEMS manufacturing processes. Selection and use of suitable measurement instrumentation. Assembly, bonding and interconnect of finished device._x000D_Atomjet: Design and sourcing of piezo-actuator to provide the motive force for the pump. Design of fluidic structures, modelling and characterization of realized pump. Selection and use of suitable measurement instrumentation. Assembly, bonding and interconnect of finished device.

Acronym MICROPUMP (Reference Number: 7275)
Duration 01/07/2012 - 30/06/2015
Project Topic The MICROPUMP Ps LioniX and Atomjet will develop a small micropump based on piezoelectric actuation aiming for a constant flowrate at constant pressure. Possible application areas are ink-jet, electronics cooling, lab on chip and bio-medical technologies
Project Results
(after finalisation)
The CO goal of the project was to create a micropump in which piezoelectric wafers were combined with silicon based MEMS technology. Besides the final "endproduct" of the project also the manufacturing process was developed in the course of this process. The development of the final product turned out to be much more complex than originally anticipated at the time the proposal was submitted. We were therefore also not able to realize a full functional demonstrator within the project, but fortunately the fabrication processes that were developed were also of key importance to the roadmap. One very important manufacturing step for instance on the LioniX side is the epoxy bonding of 2 processed wafers on top of each other. The process which was developed within this project is now also used to seal with a glassplate MEMS components that LioniX realizes for their customers. This is therefore an enabling technology for new applications and customers. Another manufacturing step that was further developed is the deep etching of the silicon wafers to allow the designs for the micropump. These specific optimized deep etching steps are now for instance also used in the manufacturing of microneedles that are created in silicon wafers._x000D__x000D_The CO result of the project is therefore not a full functional demonstrator, but the building blocks for other applications and also the close collaboration with Atomjet in the project is seen a a very important benefit of the project to enable new applications together in the future.
Network Eurostars
Call Eurostars Cut-Off 8

Project partner

Number Name Role Country
2 LioniX bv Coordinator Netherlands
2 Atomjet Partner United Kingdom