High Isolation GaAs MMIC Doubler

MMD-1648L

Page 5

Copyright © 2019 Marki Microwave, Inc. | Rev. A

Mounting and Bonding Recommendations

Marki MMICs should be attached directly to a ground plane with conductive epoxy. The ground plane electrical impedance

should be as low as practically possible. This will prevent resonances and permit the best possible electrical performance.

Datasheet performance is only guaranteed in an environment with a low electrical impedance ground.

Mounting - To epoxy the chip, apply a minimum amount of conductive epoxy to the mounting surface so that a thin epoxy fillet

is observed around the perimeter of the chip. Cure epoxy according to manufacturer instructions.

Wire Bonding - Ball or wedge bond with 0.025 mm (1 mil) diameter pure gold wire. Thermosonic wirebonding with a nominal

stage temperature of 150 °C and a ball bonding force of 40 to 50 grams or wedge bonding force of 18 to 22 grams is

recommended. Use the minimum level of ultrasonic energy to achieve reliable wirebonds. Wirebonds should be started on the

chip and terminated on the package or substrate. All bonds should be as short as possible <0.31 mm (12 mils).

Circuit Considerations

– 50 Ω transmission lines should be used for all high frequency connections in and out of the chip.

Wirebonds should be kept as short as possible, with multiple wirebonds recommended for higher frequency connections to

re

duce parasitic inductance. In circumstances where the chip more than .001” thinner than the substrate, a heat spreading

spacer tab is optional to further reduce bondwire length and parasitic inductance.

Handling Precautions

General Handling: Chips should be handled with a vacuum collet when possible, or with sharp tweezers using well trained

personnel. The surface of the chip is fragile and should not be contacted if possible.

Static Sensitivity: GaAs MMIC devices are subject to static discharge, and should be handled, assembled, tested, and

transported only in static protected environments.

Cleaning and Storage: Do not attempt to clean the chip with a liquid cleaning system or expose the bare chips to liquid.

Once the ESD sensitive bags the chips are stored in are opened, chips should be stored in a dry nitrogen atmosphere.

Bonding Diagram

Input

Output

Minimum

Space Gap/

Wirebond

Length

Multiple

Wirebonds

for Reduced

Inductance