Direct Writing of Conventional Thick Film Inks Using MAPLE-DW Process

Polymer thick film (PTF) resistors were fabricated using a new laser-based transfer technique called matrix-assisted pulsed laser evaporation direct write (MAPLE-DW). MAPLE-DW is a versatile direct writing technique capable of writing a wide variety of materials on virtually any substrate in air and at room temperature. Epoxy-based PTF resistors spanning four decades of sheet resistances (10 Ω/sq. to 100 kΩ/sq.) were deposited on alumina substrates under ambient conditions. Electrical characteristics of these MAPLE-DW deposited resistors were studied at a wide frequency range (1 MHz to 1.8 GHz), and the results were explained through an equivalent circuit model and impedance spectroscopy. Temperature coefficient of resistance measurements for the PTF resistors were performed between 25 and 125 °C. The results based on the percolation theory were used to explain the temperature dependence of the resistance behavior of the PTF resistors.

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Direct fabrication of SnO2-based thick film gas sensor using Micropen direct writing and laser microcladding

Sensors and Actuators B Chemical ◽

10.1016/j.snb.2009.01.007 ◽

2009 ◽

Vol 137 (1) ◽

pp. 340-344 ◽

Cited By ~ 14

Author(s):

Zhixiang Cai ◽

Xiangyou Li ◽

Xiaoyan Zeng

Keyword(s):

Thick Film ◽

Gas Sensor ◽

Direct Writing ◽

Direct Fabrication

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Microfluidic Device Fabrication Method Using Direct Thick Film Writing

ASME 3rd International Conference on Microchannels and Minichannels, Part B cont’d ◽

10.1115/icmm2005-75059 ◽

2005 ◽

Author(s):

William J. Grande ◽

Gary A. Fino

Keyword(s):

Rapid Prototyping ◽

Thick Film ◽

Writing Process ◽

Microfluidic Devices ◽

Device Fabrication ◽

Fabrication Method ◽

Direct Writing ◽

General Applicability ◽

Novel Technique ◽

Capillary Tip

A novel technique based on direct thick film writing has been developed for the rapid prototyping of microfluidic devices. The direct writing process is based on pressure driven dispensing of precursor materials through a micro-capillary tip. The process exhibits wide latitude in both the materials that can be patterned and the substrate formats and shapes that can be accommodated. A fabrication process flow sequence with general applicability to microfluidic devices was developed and its efficacy was demonstrated by the construction of two-input mixer devices. Integration of fluidic components with electrical circuitry was also demonstrated.

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Aerosol Jet Direct Writing Polymer-Thick-Film Resistors for Printed Electronics

Journal of Surface Mount Technology ◽

10.37665/smt.v34i1.13 ◽

2021 ◽

Vol 34 (1) ◽

pp. 24-31

Author(s):

James Feng ◽

Anthony Loveland ◽

Michael Renn

Keyword(s):

Thick Film ◽

Screen Printing ◽

Printed Circuit Board ◽

Printed Electronics ◽

Electronics Industry ◽

Circuit Board ◽

Print Quality ◽

Direct Write ◽

Direct Writing ◽

Fixed Amount

To improve performance and reduce size of printed-circuit board (PCB) in electronics industry, embedding discrete components within a board substrate has been an effective approach by reducing solder joints and their associated impedance mismatching, inductive reactance, etc. With its unique capabilities for non-contact precision material deposition, the Aerosol Jet® direct-write technology has been enabling additive manufacturing of fine-feature electronics conformally onto flexible substrates of complicated shapes. The CAD/CAM controlled relative motions between substrate and print head allows convenient adjustment of the pattern and pile height of deposited material at a given ink volumetric deposition rate. To date in the printed electronics industry, additively printing embedded polymer-thick-film (PTF) resistors has mostly been done with screen printing using carbon-based paste inks. Here we demonstrate results of Aerosol Jet® printed PTF resistors of resistance values ranging from ~50 W to > 1 kW, adjustable (among several variable parameters) by the number of stacked layers (or print passes with each pass depositing a fixed amount of ink) between contact pads of around 1 mm apart with footprint line typically < 0.3 mm. In principle, any ink material that can be atomized into fine droplets of 1 to 5 microns can be printed with the Aerosol Jet® system. However, the print quality such as line edge cleanliness can significantly influenced by ink rheology which involves solvent volatility, solids loading, and so on. Our atomizable carbon ink was made by simply diluting a screen printing paste with a compatible solvent of reasonable volatility, which can be cured at temperatures below 200 oC. We show that Aerosol Jet® printed overlapping lines can be stacked to large pile height (to reduce the resistance value) without significant increase of line width, which enables fabricating embedded resistors with adjustable resistance values in a limited footprint space.

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Study on thick-film PTC thermistor fabricated by micro-pen direct writing

Microelectronics Journal ◽

10.1016/j.mejo.2008.04.019 ◽

2008 ◽

Vol 39 (12) ◽

pp. 1452-1456 ◽

Cited By ~ 7

Author(s):

Zhixiang Cai ◽

Xiangyou Li ◽

Qianwu Hu ◽

Xiaoyan Zeng

Keyword(s):

Thick Film ◽

Direct Writing

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Scanning Electron Microscopy in Hybrid Microelectronics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100092244 ◽

1976 ◽

Vol 34 ◽

pp. 456-457

Author(s):

S. Khadpe ◽

R. Faryniak

Keyword(s):

Integrated Circuits ◽

Thick Film ◽

Integrated Circuit ◽

Failure Modes ◽

Three Dimensional ◽

Circuit Components ◽

Hybrid Microcircuit ◽

Electrical Connections ◽

Scanning Electron

The Scanning Electron Microscope (SEM) is an important tool in Thick Film Hybrid Microcircuits Manufacturing because of its large depth of focus and three dimensional capability. This paper discusses some of the important areas in which the SEM is used to monitor process control and component failure modes during the various stages of manufacture of a typical hybrid microcircuit.Figure 1 shows a thick film hybrid microcircuit used in a Motorola Paging Receiver. The circuit consists of thick film resistors and conductors screened and fired on a ceramic (aluminum oxide) substrate. Two integrated circuit dice are bonded to the conductors by means of conductive epoxy and electrical connections from each integrated circuit to the substrate are made by ultrasonically bonding 1 mil aluminum wires from the die pads to appropriate conductor pads on the substrate. In addition to the integrated circuits and the resistors, the circuit includes seven chip capacitors soldered onto the substrate. Some of the important considerations involved in the selection and reliability aspects of the hybrid circuit components are: (a) the quality of the substrate; (b) the surface structure of the thick film conductors; (c) the metallization characteristics of the integrated circuit; and (d) the quality of the wire bond interconnections.

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Instrumentation for Measurement of Lingual Strength

Journal of Speech and Hearing Research ◽

10.1044/jshr.1101.189 ◽

1968 ◽

Vol 11 (1) ◽

pp. 189-193 ◽

Cited By ~ 1

Author(s):

Lois Joan Sanders

Keyword(s):

Single Channel ◽

Displacement Transducer ◽

Tongue Pressure ◽

Maximum Pressure ◽

Research Use ◽

Direct Writing ◽

Significant Difference ◽

Pressure Unit ◽

Force Displacement ◽

Consistent Response

A tongue pressure unit for measurement of lingual strength and patterns of tongue pressure is described. It consists of a force displacement transducer, a single channel, direct writing recording system, and a specially designed tongue pressure disk, head stabilizer, and pressure unit holder. Calibration with known weights indicated an essentially linear and consistent response. An evaluation of subject reliability in which 17 young adults were tested on two occasions revealed no significant difference in maximum pressure exerted during the two test trials. Suggestions for clinical and research use of the instrumentation are noted.

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