Bonding wire interconnection de-embedding for GaN high electron mobility transistor loadpull measurement with...

Area of Science:

• Electrical Engineering
• Materials Science

Background:

• High-power gallium nitride high electron mobility transistors (GaN HEMTs) require specialized test fixtures.
• Wire bonding is a common interconnection method, but bonding wires introduce significant parasitic elements.
• Accurate de-embedding of these parasitic effects is essential for S parameter and load-pull measurements.

Purpose of the Study:

• To develop and validate a method for accurately measuring and modeling the parasitic inductance of bonding wires in GaN HEMTs.
• To improve the accuracy of device measurements and modeling by accounting for bonding wire effects.

Main Methods:

• Design of test fixtures with high power capacity and impedance matching networks.
• Development of through-reflect-line (TRL) calibration kits for S parameter measurements.
• Utilizing vector network analyzers (VNAs) for measurements.
• Employing electromagnetic (EM) simulation and compact circuit models to extract equivalent inductances.
• Characterization of Cree's CGHV1J006D GaN HEMT.

Main Results:

• The proposed method accurately characterizes bonding wire interconnections, yielding good agreement between extracted equivalent inductances and models.
• Equivalent inductance of a 2 mm gate-width transistor bonding wire was successfully obtained using the EM model.
• De-embedding bonding wire effects enabled accurate calculation of drain impedance, aligning with load-line theory.

Conclusions:

• The developed test fixture and calibration kit approach provides an effective and accurate means to characterize bonding wire inductance.
• Accurate modeling and de-embedding of bonding wire parasitics are vital for precise high-power GaN HEMT measurements and device modeling.
• This work contributes to more reliable performance prediction and design of high-power GaN devices.