In the past few years, 3D printing technology has witnessed an explosive growth, penetrating various aspects of our lives. Current best-in-class 3D printers can fabricate micrometer scale objects, which has made fabrication of microfluidic devices possible. The highest achievable resolution is already at nanometer scale, which is continuing to drop. Since geometric complexity is not a concern for 3D printing, novel 3D microfluidics and lab-on-a-chip systems that are otherwise impossible to produce with traditional 2D microfabrication technology have started to emerge in recent years. In this review, we first introduce the basics of 3D printing technology for the microfluidic community and then summarize its emerging applications in creating novel microfluidic devices. We foresee widespread utilization of 3D printing for future developments in microfluidic engineering and lab-on-a-chip technology.

3D printing: an emerging tool for novel microfluidics and lab-on-a-chip applications

A heat exchanger and method of manufacturing thereof comprises an interface layer for cooling a heat source. The interface layer is coupled to the heat source and is configured to pass fluid therethrough. The heat exchanger further comprises a manifold layer that is coupled to the interface layer. The manifold layer includes at least one first port that is coupled to a first set of individualized holes which channel fluid through the first set. The manifold layer includes at least one second port coupled to a second set of individualized holes which channel fluid through the second set. The first set of holes and second set of holes are arranged to provide a minimized fluid path distance between the first and second ports to adequately cool the heat source. Preferably, each hole in the first set is positioned a closest optimal distance to an adjacent hole the second set.

Method and apparatus for efficient vertical fluid delivery for cooling a heat producing device

A vapor escape membrane for use in a heat exchanging device, including a heat pipe or heat sink that runs liquid into a cooling region positioned adjacent to the heat producing device, the vapor escape membrane comprising: a porous surface for removing vapor produced from the liquid in the cooling region, the membrane configured to confine the liquid only within the cooling region. The vapor escape membrane transfers vapor to a vapor region within the heat exchanging device, wherein the membrane is configured to prevent liquid in the cooling region from entering the vapor region. The membrane is configured to include a hydrophobic surface between the membrane and the cooling region, wherein the liquid in the cooling region does not flow through the porous surface. The vapor escape membrane includes a plurality of apertures for allowing vapor to transfer therethrough, each of the apertures having a predetermined dimension.

Vapor escape microchannel heat exchanger

The invention encompasses analyzers and analyzer systems that include a single particle analyzer, methods of using the analyzers and analyzers systems to analyze samples, either for single particles or for multiple particles (multiplexing), methods of doing business based on the use of the analyzers or analyzer systems of the system, and electronic media for storing parameters useful in the analyzers and analyzer systems of the invention.

System and methods for sample analysis

A microchannel heat exchanger coupled to a heat source and configured for cooling the heat source comprising a first set of fingers for providing fluid at a first temperature to a heat exchange region, wherein fluid in the heat exchange region flows toward a second set of fingers and exits the heat exchanger at a second temperature, wherein each finger is spaced apart from an adjacent finger by an appropriate dimension to minimize pressure drop in the heat exchanger and arranged in parallel. The microchannel heat exchanger includes an interface layer having the heat exchange region. Preferably, a manifold layer includes the first set of fingers and the second set of fingers configured within to cool hot spots in the heat source. Alternatively, the interface layer includes the first set and second set of fingers configured along the heat exchange region.

Interwoven manifolds for pressure drop reduction in microchannel heat exchangers

Microfluidic devices are disclosed which can be manufactured using surface-micromachining. These devices utilize an electroosmotic force or an electromagnetic field to generate a flow of a fluid in a microchannel that is lined, at least in part, with silicon nitride. Additional electrodes can be provided within or about the microchannel for separating particular constituents in the fluid during the flow based on charge state or magnetic moment. The fluid can also be pressurized in the channel. The present invention has many different applications including electrokinetic pumping, chemical and biochemical analysis (e.g. based on electrophoresis or chromatography), conducting chemical reactions on a microscopic scale, and forming hydraulic actuators.

Surface-micromachined microfluidic devices

We have developed a computational model to optimize the design of a surface reflection neutralization source of hyperthermal neutrals for charge‐free processing. For the deployment of this technique to production (≥8 in. wafers) processing, a system design study has been completed. A Monte Carlo model is used to determine the energy and angular distributions of reflected hyperthermal neutrals at the surface of a wafer, as well as flux uniformity. A simple form for the plasma profile is chosen to allow simulation of various profiles reported in the literature. Neutrals are launched from the reflector consistent with the relative plasma density at each position on the reflector with angular and energy distributions consistent with experimental observations. These neutrals are then followed through interactions with thermal background atoms and the plasma. Charge exchange, ionization, and elastic scattering processes are considered for argon as the main feedstock gas. The results show the trade off between a...

Simulation of a surface-reflection neutral stream source

Experimental studies of a broad-area hyperthermal neutral stream source for photoresist cleaning are reported. Low energy neutrals are generated from a high-density inductively coupled plasma by the surface reflection neutralization method. Rates of removal of photoresist polymers such as polymethyl methacrylate as functions of the hyperthermal translational energy and background neutral pressure are reported. The results demonstrate this low energy neutral source provides controllable fast neutrals for cleaning applications. Ex situ and in situ measurements yield typical removal rates of about 10 A/s without stream collimation. The removal rates at increasing pressures show a trade-off between creating higher density plasma, leading to a greater initial neutral flux and attenuation of neutrals due to collisions. These observations are in good agreement with previous Monte Carlo simulations. The removal rate increases linearly with rf power and is nearly constant as the neutral energy is varied by varying...

Christopher A. Nichols

Papers

Surface-micromachined microfluidic devices

Simulation of a surface-reflection neutral stream source

Stripping and cleaning of photoresist using low energy neutrals