MILESTONES
& FUTURE WORK
During 2002, our group worked with Motorola on developing a high-frequency bond-wire model for use in ADS. A 3-D bond-wire model was created and simulated in Ansoft’s High Frequency Structure Simulator (HFSS), and then validated with measured bond-wire results from Motorola as seen in Fig. 1. Next, design parameters such as wire length and wire diameter were varied in HFSS, in order to observe their effect on the device characteristics (e.g., S-parameters). Lumped-element & transmission-line models (see Fig. 2) were then developed in ADS, and optimized to fit the HFSS S-parameter data as seen in Fig. 3. Finally, the ADS optimized model components were curve fitted into “engineering design equations” using MATLAB.
FURTURE
TASKS::
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Continue with the development of models for accurate high frequency characterization of other interconnects of interest to Motorola |
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Develop
new high frequency models for advanced packaging
procedures including flip-chip/Bump packaging,
coupled lines single and multiple vias, and
the accurate simulation of impeded and inverted
grounding. |
| • |
Develop
new models for packaging using new materials
( e.g. polymers) and examine the effects of
substrates/superstrates dimensions and material
type |
| • |
Extend above models to include designs based on coplanar waveguide designs
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Fig. 2. Transmission-line bond-wire model in ADS. TL1 is a high-impedance transmission line that represents the bond wire. C1 and C2 are capacitors that represent the capacitance between the bond wire and the ground plane.
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DELIVERABLES:
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ADS high-frequency interconnect models for use in MMW applications |
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Accurate characterization of interconnects at frequencies up to 65 GHz |
| • |
HFSS project files, including 3-D models, material & boundary assignments, source definitions, and simulation results (S-parameters & field solutions) |
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