The MA4E2502 SURMOUNTTM Series Diodes are
Silicon Low, Medium, and High Barrier Schottky
Devices fabricated with the patented Heterolithic
Microwave Integrated Circuit (HMIC™) process.
HMIC™ circuits consist of Silicon pedestals which
form diodes or via conductors embedded in a glass
dielectric, which acts as the low dispersion, microstrip
transmission medium. The combination of
silicon and glass allows HMIC™ devices to have excellent
loss and power dissipation characteristics in
a low profile, reliable device.
The Surmount Schottky devices are excellent
choices for circuits requiring the small parasitics of
a beam lead device coupled with the superior mechanical
performance of a chip. The Surmount
structure employs very low resistance silicon vias
to connect the Schottky contacts to the metalized
mounting pads on the bottom surface of the chip.
These devices are reliable, repeatable, and a lower
cost performance solution to conventional devices.
They have lower susceptibility to electrostatic discharge
than conventional beam lead Schottky diodes.
The multilayer metallization employed in the fabrication
of the Surmount Schottky junctions includes
a platinum diffusion barrier, which permits all devices
to be subjected to a 16-hour non-operating
stabilization bake at 300°C.
The “0502” outline allows for Surface Mount placement
and multi-functional polarity orientations.
The MA4E2502 Family of Surmount Schottky diodes
are recommended for use in microwave circuits
through Ku band frequencies for lower power
applications such as mixers, sub-harmonic mixers,
detectors, and limiters. The HMIC construction
facilitates the direct replacement of more fragile
beam lead diodes with the corresponding Surmount
diode, which can be connected to a hard or
soft substrate circuit with solder.