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HMC561_09 Datasheet, PDF (6/6 Pages) Hittite Microwave Corporation – GaAs MMIC x2 ACTIVE FREQUENCY MULTIPLIER, 8 - 21 GHz OUTPUT
v02.0809
HMC561
GaAs MMIC x2 ACTIVE FREQUENCY
MULTIPLIER, 8 - 21 GHz OUTPUT
Mounting & Bonding Techniques for Millimeterwave GaAs MMICs
The die should be attached directly to the ground plane eutectically or with
conductive epoxy (see HMC general Handling, Mounting, Bonding Note).
0.102mm (0.004”) Thick GaAs MMIC
2
50 Ohm Microstrip transmission lines on 0.127mm (5 mil) thick alumina thin film
substrates are recommended for bringing RF to and from the chip (Figure 1). If
0.254mm (10 mil) thick alumina thin film substrates must be used, the die should
be raised 0.150mm (6 mils) so that the surface of the die is coplanar with the
surface of the substrate. One way to accomplish this is to attach the 0.102mm
(4 mil) thick die to a 0.150mm (6 mil) thick molybdenum heat spreader (moly-tab)
which is then attached to the ground plane (Figure 2).
Microstrip substrates should be brought as close to the die as possible in order
to minimize ribbon bond length. Typical die-to-substrate spacing is 0.076mm (3
mils). Gold ribbon of 0.075 mm (3 mil) width and minimal length <0.31 mm (<12
mils) is recommended to minimize inductance on RF, LO & IF ports.
An RF bypass capacitor should be used on the Vdd input. A 100 pF single layer
capacitor (mounted eutectically or by conductive epoxy) placed no further than
0.762mm (30 Mils) from the chip is recommended.
0.076mm
(0.003”)
Wire 3 mil Ribbon Bond
RF Ground Plane
0.127mm (0.005”) Thick Alumina
Thin Film Substrate
Figure 1.
Handling Precautions
Follow these precautions to avoid permanent damage.
Storage: All bare die are placed in either Waffle or Gel based ESD protective
containers, and then sealed in an ESD protective bag for shipment. Once the
sealed ESD protective bag has been opened, all die should be stored in a dry
nitrogen environment.
0.102mm (0.004”) Thick GaAs MMIC
0.076mm
(0.003”)
Ribbon Bond
Cleanliness: Handle the chips in a clean environment. DO NOT attempt to clean
the chip using liquid cleaning systems.
Storage: All bare die are placed in either Waffle or Gel based ESD protective
containers, and then sealed in an ESD protective bag for shipment. Once the
sealed ESD protective bag has been opened, all die should be stored in a dry
nitrogen environment.
Static Sensitivity: Follow ESD precautions to protect against > ± 250V ESD
strikes.
RF Ground Plane
0.150mm (0.005”) Thick
Moly Tab
0.254mm (0.010”) Thick Alumina
Thin Film Substrate
Figure 2.
Transients: Suppress instrument and bias supply transients while bias is applied. Use shielded signal and bias cables to minimize
inductive pick-up.
General Handling: Handle the chip along the edges with a vacuum collet or with a sharp pair of bent tweezers. The surface of the
chip may have fragile air bridges and should not be touched with vacuum collet, tweezers, or fingers.
Mounting
The chip is back-metallized and can be die mounted with AuSn eutectic preforms or with electrically conductive epoxy. The
mounting surface should be clean and flat.
Eutectic Die Attach: A 80/20 gold tin preform is recommended with a work surface temperature of 255 deg. C and a tool temperature
of 265 deg. C. When hot 90/10 nitrogen/hydrogen gas is applied, tool tip temperature should be 290 deg. C. DO NOT expose the
chip to a temperature greater than 320 deg. C for more than 20 seconds. No more than 3 seconds of scrubbing should be required
for attachment.
Epoxy Die Attach: Apply a minimum amount of epoxy to the mounting surface so that a thin epoxy fillet is observed around the
perimeter of the chip once it is placed into position. Cure epoxy per the manufacturer’s schedule.
Wire Bonding
Ball or wedge bond with 0.025mm (1 mil) diameter pure gold wire. Thermosonic wirebonding with a nominal stage temperature of
150 deg. 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 <0.31mm (12 mils).
For price, delivery, and to place orders, please contact Hittite Microwave Corporation:
20 Alpha Road, Chelmsford, MA 01824 Phone: 978-250-3343 Fax: 978-250-3373
Order On-line at www.hittite.com
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