Monodisperse Droplet Generator

MSP Corporation Announces a New Breakthrough in Monodisperse Droplet Generation

1530 MONODISPERSE DROPLET GENERATOR CALIBRATION SYSTEM

(PRWeb Press Release) Shoreview, Minnesota April 18, 2017

Summary: MSP's newly developed Model 1530 Monodisperse Droplet Generator (MDG) produces uniform monodisperse droplets as small as 15 microns in diameter. The 1530's small high precision droplets are very useful for evaluating the performance of laboratory laser phase Doppler systems.

Quote:The MDG produces small droplets without the clogging problems that a VOAG device typically has with very small orifices.

The Vibrating Orifice Aerosol Generator (VOAG) was developed in the 1970s and has been a key device for generating monodisperse droplets of known diameters for research applications such as for calibrating droplet measuring instruments, for studying droplet processes and for generating monodisperse solid particles by drying monodisperse droplets.

The VOAG requires forcing liquid out of an orifice about half the diameter of the desired droplets. Liquid jet emerging from the orifice is broken down uniformly using narrow-bandwidth ultrasonic excitations, so a single drop is formed during each cycle of ultrasonic perturbation. Diameters of the droplets thus produced are determined with a high accuracy as they carry the liquid volume forced out of the orifice in a single cycle of ultrasonic perturbation.

However, this excellent process of generating monodisperse droplets of known diameters becomes unreliable and difficult to implement with decreasing orifice diameters, as small orifices are prone to clogging and wear out under liquid pressure, thus making it difficult to generate small droplets. Over years, there has been a growing need for sub-50-micron droplets that cannot be easily produced using the VOAG device. MSP has recently solved this problem by using the ‘flow-focusing’ technique in combination with ultrasonic liquid jet breakup (patent pending). The newly developed Model 1530 Monodisperse Droplet Generator (MDG) uses a robust nozzle with a 100-micron diameter opening that is neither prone to wear nor clogging under normal operating conditions. The liquid jet issuing from the nozzle is attenuated to the desired diameter using flow-focusing air, which flows concentric to the liquid jet and accelerates it, thus reducing the jet diameter. The amount of energy in the flow-focusing air, controlled by its initial pressure, determines the final jet diameter, which can be as small as 10 microns.

The Model 1530 MDG has been extensively tested with ultrapure water and organic solvents (e.g. methanol and ethyl alcohol) and shown to generate a wide-range of droplet diameters from nearly 15 microns up to 100 microns. Unlike the VOAG, the MDG does not require hardware reconfiguration to cover this wide droplet size range. Tables and graphs are provided to choose operating conditions for generating the desired droplet diameters.

Using a touchscreen menu and a flow metering valve, Model 1530 provides convenient and user-friendly means to set three key parameters: liquid flow rate, ultrasonic frequency and flow-focusing air pressure. Proper choice of these parameters ensures stable output of monodisperse droplets of the desired size with a geometric standard deviation of 1.01-1.03. The droplet generating head is connected to the main body of the instrument via flexible tubing and an electrical signal cable, so it can be positioned with an arbitrary orientation at the desired location in an experimental setup, such as a setup involving characterization of sprays using the phase Doppler technique.

MSP is a privately-held division of TSI Inc. For over 30 years MSP has created micro- and nano-particle instrument and equipment technologies for scientific research and industrial applications. MSP is known world-wide for particle technology expertise in helping researchers and manufacturers solve tough problems with creative equipment designs. Contact MSP at sales(at)mspcorp(dot)com to discuss micro- and nano-particle application or research needs.

Contact: Francisco J. Romay, Product Manager, Aerosol Instruments

Original press release can be found at http://www.prweb.com/releases/2017/03/prweb14170934.htm

Cascade Impactor Technology Leaps Forward with MSP’s latest real-time QCM-MOUDI™ Impactor

Real-Time QCM-MOUDI™ Impactor

MSP’s real-time QCM-MOUDI™ Impactor is a leap forward in cascade impactor technology for size-fractionation and mass measurement of aerosols. The new QCM-MOUDI™ has a 25-nanogram mass resolution which is accomplished through humidity control and advanced electronics, while keeping samples available for post-collection analysis.

Researchers can now accelerate their aerosol studies by measuring aerosol mass in real-time with the breakthrough equipment technology contained in the QCM-MOUDI™ Impactor device from MSP.

Cascade Impactor History background

Cascade impactors have been used for collecting and size-fractionating aerosols for over a century. Significant advances were made in this technology in the late 1970s and early 1980s by MSP founders at the University of Minnesota. In particular, collection of nanometer particles (<100 nm) was enabled, and a uniform deposit feature was introduced (see Kuhlmey et al. 1981 and Marple et al. 1981). These advancements led to the Micro-Orifice Uniform Deposit Impactors (MOUDI™) introduced as commercial products by MSP Corporation. These precision cascade impactors are designed for sampling and collecting size-fractionated particle samples for gravimetric and/or chemical analyses. Several models of the MOUDI™ product line cover flow rates as high as 30 L/min and the lowest cut-sizes as small as 10 nm. The MOUDI differs from other conventional cascade impactors in the use of a large number of micro-orifice nozzles to reduce jet velocity and pressure drop, minimize particle bounce and re-entrainment, and enhance collection efficiency. As many as 6,000 nozzles with diameters as small as 50 μm are used. Some models also have the uniform-deposit feature achieved by rotating the impaction plate relative to the nozzles so that the particle deposits under the nozzles can be spread out uniformly over the entire impaction area.

MSP research yields the real-time QCM-MOUDI™

This new capability enables researchers to actively monitor aerosol mass measurements, while simultaneously collecting size-fractionated samples for post-collection analysis.

A Quartz Crystal Microbalance (QCM) is a sub-millimeter thick wafer cut out of a single crystal of quartz. Metallic films deposited on both sides of the wafer serve as electrodes that are used to probe the natural frequency of vibration of the QCM. QCMs can be mounted to the impaction surfaces of cascade impactors. The aerosol mass depositing on them results in a drop in the frequency proportional to the deposited mass. QCM surfaces can be cleaned after a measurement session and reused.

Early attempts to utilize QCMs for real-time aerosol mass measurement were hampered by technological problems including the failure of the aerosol to remain attached to the QCM as it vibrated at MHz frequencies. After meticulous investigation of the earlier anomalies in QCM response, MSP has developed a proprietary technology to reliably measure size-fractionated aerosol masses up to 100 micrograms. In particular, humidity conditioning of the sampled aerosol ensures reliable coupling of aerosols to QCMs (patent pending).

For over 30 years MSP has created micro- and nano-particle instrument and equipment technologies for scientific research and industrial applications. MSP is known world-wide for particle technology expertise in helping researchers and manufacturers solve tough problems with creative equipment designs. Contact MSP at sales(at)mspcorp(dot)com to discuss micro- and nano-particle application or research needs.

For the original version on PRWeb visit: http://www.prweb.com/releases/real-time-moudi-impactor/cascade-impactor/prweb13702090.htm

MSP’s Nano-Particle VPG Filter

MODEL 2920-A3 VAPOR/GAS PROCESSING FILTER(VPG™)

MSP’s Nano-Particle VPG Filter Achieves Ultra-High Filter Efficiency (twelve 9s)

(PRWeb Press Release) Shoreview, Minnesota June 28, 2016

MSP’s ultra-high efficiency semiconductor Vapor and Process Gas (VPG) filters achieve the highest filtration industry efficiency rating, twelve 9s or 99.9999999999% at 2.5nm, for semiconductor application. VPG filters remove particles from low pressure, high temperature gas/vapor mixtures for use in atomic layer deposition (ALD) and chemical vapor deposition (CVD) applications.

The Model 2920 VPG Filter™ is an ultra- high efficiency filter designed for Vapor and Process Gas filtration. The VPG Filter has an estimated particle penetration of less than one part per trillion and a filter efficiency of 99.9999999999% (twelve 9s) at 2.5 nm. This 2.5nm, part-per-trillion particle penetration, twelve-9 efficiency rated filter is the highest rated filter in the filtration industry for semiconductor applications. Conventional high-purity, point-of-use gas filters are used in a compressed gas line for particle removal. In contrast, the VPG™ filter is generally used downstream of a vaporizer under vacuum flow conditions to remove particles from a gas/vapor mixture with the carrier gas—such as nitrogen, argon or helium—being mixed with a chemical precursor vapor containing hafnium, zirconium, or other elemental species of interest for atomic layer deposition (ALD) as well as chemical vapor deposition (CVD) applications. FILTER EFFICIENCY The particle removal efficiency of a compressed gas filter can be determined directly by counting particles upstream and downstream of a filter by a laser particle counter, or a condensation particle counter. The efficiency of a vapor and process gas filter can only be determined indirectly by particle counting using an inert gas that is compatible with the particle counter used for the test. The measurement results can then be extended to cover conditions similar to those encountered in the actual process through mathematical modeling. For vapor/ process gas mixture filtration, the filter may be exposed to operating pressures as low as 10 Torr, temperatures as high as 300C, and chemically reactive vapor in the mixture. Direct filter efficiency measurement is generally impossible. Experimental measurement with mathematical extension provides an alternative. MSP has developed a predictive model to extend the test result obtained by a condensation particle counter under normal room temperature and pressure conditions into the vacuum flow conditions of the VPG filter in a semiconductor thin film deposition tool. For the VPG-A3 filter the particle penetration is 1 x 10**6, or 1 part per million at 100nm. At 10nm, the penetration is 1 part per billion. At the lower detection limit of the condensation particle counter of 2.5 nm, the penetration is less the 1 part per trillion. The filter efficiency is thus 99.9999% (six 9s) at 100nm, 99.9999999% (nine 9s) at 10nm, and 99.9999999999% (twelve 9s) at 2.5nm. MSP research shows that the VPG-A3 filter is an ultra-high efficiency filter capable of removing almost all particles from a gas/vapor mixture stream from 2.5nm to 100nm. In filtration, the term “absolute filter” is generally used for filters with a particle penetration that is too low to detect. The VPG-A3 filter is therefore an Absolute Nano-Particle Filter™, capable of removing substantially all nano-particles from 2.5 nm to 100 nm to a very low and essentially non-detectable level. This 2.5nm, part-per-trillion penetration, twelve 9 efficiency filter is the highest rated filter for [vapor/process gas filtration in the semiconductor industry]. PRESSURE DROP, OPERATING LIFE, AND FILM THICKNESS UNIFORMITY The particle removal efficiency is but one of several filter characteristics for vapor/process gas filtration. Other important characteristics include the filter pressure drop, the filter life, and the physical design of the filter that can influence the film thickness and its uniformity. All these factors are taken into consideration in the design of the VPG family of filters from MSP to insure reliable operation and long service life under the most demanding process environment in semiconductor film deposition processes. For over 30 years MSP has created [micro- and nano-particle instrument and equipment technologies] for scientific research and industrial applications. MSP is known world-wide for particle technology expertise in helping researchers and manufacturers solve tough problems with creative equipment designs. Contact MSP at sales(at)mspcorp(dot)com to discuss micro- and nano-particle application or research needs.

For the original version on PRWeb visit: http://www.prweb.com/releases/semiconductor/high-efficiency-filter/prweb13488487.htm

FLOW-FOCUSING MONODISPERSE AEROSOL GENERATOR

MODEL 1520 FLOW-FOCUSING MONODISPERSE AEROSOL GENERATOR™ (FMAG™)

FMAG Aerosol Generator Produces Aerosol Particles for Extended Periods

(PRWeb Press Release) Shoreview, Minnesota October 20, 2015
MSP's new Flow-Focusing Monodisperse Aerosol Generator (FMAG) produces particles for extended operational periods of time. Some aerosol generators are prone to operational clogging; however the FMAG's novel approach circumvents clogging while producing small uniform aerosol particles, allowing investigators to focus on research and not equipment difficulties.
MSP’s new Model 1520 FMAG is an aerosol generator that produces an airborne suspension of monodisperse droplets or solid, dry aerosol particles. The FMAG uses a novel flow focusing effect to break up the liquid feed stream to create aerosol particles of a uniform size, 0.7 to 15 µm in diameter. This novel approach to aerosol particle generation is particularly useful in applications requiring instrument operation over extended periods of time.
Other aerosol generators often require the use of orifices not much larger than the size of the desired particles. Instruments using these small orifices for particle generation often encounter clogging problems, limiting the instrument’s useful operation time and disrupting the research work. The FMAG circumvents the clogging with its large 100 µm-diameter orifice and creative particle generation method, thus allowing investigators to focus on research for extended periods of time without worrying about equipment difficulties. Importantly, biological cells suspended in this manner are still viable, rather than being killed by the stress of the particle generation mechanism. The FMAG can deliver a variety of solid and liquid particles of a uniform and accurately known particle size to accuracies better than ± 1%. The particles generated provide a laboratory with standard aerosols for calibrating droplet and aerosol particle sizing instruments such as laser particle counters and particle size spectrometers. The FMAG can also be used to generate known size particles at a known rate for laboratory experimentation, exposure studies and a variety of applications in other aerosol research disciplines. The FMAG’s built-in corona aerosol neutralizer generates a bipolar charge of gaseous ions to neutralize any electrical charge that may be generated during the droplet and particle formation process. This important FMAG aerosol generator feature ensures that static electricity does not skew the experimental research results. MSP’s FMAG was recently introduced at the 2015 European Aerosol Conference in Milan, Italy, and at the 34th Annual conference of the American Association for Aerosol Research (AAAR) in Minneapolis, MN. For over 30 years MSP has created micro- and nano-particle instrument and equipment technologies for scientific research and industrial applications. MSP is known world-wide for particle technology expertise in helping researchers and manufacturers solve tough problems with creative equipment designs. Contact MSP at sales@mspcorp.com to discuss micro- and nano-particle application or research needs.
For the original version on PRWeb visit: http://www.prweb.com/releases/2015/10/prweb13025822.htm