Multi-PhaseFlow Project's Collaborations with Industry

Close collaboration with industrial partners will be crucial to the success of the MultiPhaseFlow project from the outset. These industrial collaborators bring not only specialized knowledge of the physical phenomenon to be simulated, but also unique experimental facilities that can help validate Multi-PhaseFlow's numerical methods, potential educational opportunities for Multi-PhaseFlow's graduate students and postdocs, and channels for the technology transfer of Multi- PhaseFlow's results into the wider industrial and manufacturing community. The relationships that Professor Puckett and his team have already established through their prior work with the Xerox Corporation and MicroFab Technologies Inc. lay the foundation for achieving this aim in the context of MPF. Below are some links to papers that explain, with lots of images and illustration, the research and technology that MicroFab Technologies Inc. is doing in this area.

Ink-Jet Printing Technology and Background on Ink-Jet Technology (MicroFab)

Ink-Jet printing technology can reproducibly dispense spheres of fluid with diameters of 25-100µm (10pl to 0.5nl) at rates of 0-4,000 per second for single droplets on-demand, and up to 1MHz for continuous droplets. Piezoelectric dispensing technology is adaptable to a wide range of material dispensing applications, such as biomedical reagents, liquid metals, and optical polymers. Ink-jet microdispensing has been used in the manufacturing of immunoassay diagnostics and is being developed for manufacturing DNA diagnostic arrays. Rapid, accurate fluid microdispensing using ink-jet technology has the potential to increase throughput and lower cost in combinatorial drug synthesis, screening, and testing. MicroFab has developed demand mode printheads with up to 120 addressable channels in less than an inch. Miniaturization has enabled the electronics/computer age by driving down the cost and increasing the function of electronic and photonic devices. Biomedical processes, such as medical diagnostics, drug synthesis, functional screening of drugs, can utilize high density, low cost electronic and photonic devices to increase productivity. However, the fundamental physics of fluid dispensing significantly limit the degree to which these biochemical processes can miniaturize. The various technologies that are generally referred to as "ink-jet printing" have the potential to remove many of these fluid dispensing limitations.

Solder Jet Printing for Low Cost Wafer Bumping (MicroFab)

Abstract — The use of drop-on-demand ink-jet printing methods to dispense microdroplets of solder (Solder Jet Technology) for electrical interconnections in flip-chip assembly is addressed. Other applications include solder balls for BGA packages and solder for fine-line printed circuit boards. Solder Jet deposition is noncontact, data driven, flexible, and environmentally friendly. Printing of molten solder droplets, 40µm to 120µm in diameter, onto metallized wafers has been demonstrated using several solders. Solder bumps have been successfully attached both to surfaces considered highly solderable like gold (Au) and to metals considered unsolderable like aluminum (Al). Solder Jet Technology could potentially replace photolithographic/electroplating processes for wafer bumping. Process development research is underway using prototype Solder Jet equipment at Motorola, Texas Instruments, Delco Electronics, AMP and Eastman Kodak.

MicroJet Printing for Low Cost Optical Interconnects (MicroFab)

Abstract — Drop-on-demand microjet printing methods are being developed for the formation of optical interconnections. Microdroplets of optical polymeric materials, 25-50µm in diameter, are dispensed at temperatures up to 220C onto optical substrates and components, in order to create precisely placed & formed micro-optical elements 40-1,000µm in size. Micro-optical elements fabricated in this way include arrays of spherical and anamorphic microlenses, lenslets on the tips of optical fibers, optical waveguides and fiber-to-fiber optical interconnects. Advantages of the microjet printing method for micro-optics manufacture include: low cost (e.g., no photomasks and low material usage); flexible and automated (e.g., custom microlens arrays for diode laser array coupling into optical fibers); and in situ, non-planar processing (e.g., direct deposit of microlenses and waveguides onto flat, curved or flexible optical substrates as a value-added processing step).

Photo-Realistic Ink-Jet Printing Through Dynamic Spot Size Control (MicroFab)

Abstract — A method has been developed for dynamically modulating the drop volume created by an array piezoelectric drop-on-demand ink-jet printhead. A 4:1 range of volume modulation has been achieved to date, resulting in approximately a 4:1 range in printed spot area. The modulation is continuous (i.e., not discrete) over a significant part of the total range, and is achieved with a minimal decrease in throughput. Optical densities for modulated spots have been measured at 300 and 600 dpi for several printhead configurations. Algorithms have been designed to use a combination of continuous modulation and halftoning (using modulated drops) to produce photo-realistic images.