This research was developed with funding from the Defense Advanced Research Projects Agency (DARPA).

The views, opinions and/or findings expressed are those of the author and should not be interpreted as representing the official views or policies of the Department of Defense or the U.S. Government.

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Heterogeneous 3D

Progress Towards a 40nm GaN FoundryFlorian Herrault, Andrea Corrion, Daniel Denninghoff, Michael Johnson, Erdem Arkun, Ignacio Ramos, Joel Wong, Shawn Burnham, Ara Kurdoghlian, David Chow – HRL Laboratories, LLC

mm-wave GaN Maturation Program (MGM)

Background Results and ImpactApproach

The DARPA MTO NEXT Program established

the world’s fastest GaN technology at HRL

Cycle time improvement of

HRL T3 GaN

T3 GaN

Today

T3 GaN

Phase 1

MECAMIC

Phase 1

Cycle

Tim

e R

ela

tive t

o T

3 G

aN

Today

Back-end-of-line

Front-end-of-line

100%

60%

19%

HRL’s GaN T3 and T4A device technologies

enable unprecedented millimeter-wave

phased-array radar power and efficiency

MGM Program: 1) Process maturation to

enhance production readiness 2) provide

external access to HRL technology, and 3)

develop novel manufacturing techniques with

unprecedented low cycle time & cost

• Decrease T3 cycle time by 40%

through re-engineering process

flow to alleviate bottlenecks and

redundancies & equipment

acquisition

• Physics-of-failure & targeted

experimentation to increase T3

fabrication yield by 50%

• Develop novel manufacturing

approach (Metal-Embedded

Copper Chip Assembly

Microwave ICs = MECAMIC) for

unprecedented short cycle time

• Advance Manufacturing

Readiness Level (MRL) to 6

• T3 Ka-band MMIC: >4 Watts, >40% efficiency

• T4A W-band MMIC: >0.5 Watts, >35% efficiency

Optimization of critical processing steps with

decreased cycle time

SiC etcher acquisition

Robust 40-nm gate process

Process Design Kit (PDK) improvements, high-

power Ka-band & W-band amplifiers, MPW

Foundry runs available to external customers,

Metal-Embedded Chip Assembly for Microwave

Integrated Circuits (MECAMIC) for potential

unprecedented short cycle time

All images author’s own

At Ka-band

Process HRL T2 HRL T3 HRL T4a

Key Feature BaselineVertical & Lateral

Scaling

Asymmetric Self-

Aligned Gate,

3D n+ Contact

Gate Length 150 nm 40 nm 20 nm

fT/fMAX 90/220 GHz 200/400 GHz 320/550 GHz

Breakdown >40 V >40 V 17 V

New data

(MGM)

Application Pull & Circuit DemonstrationsAll images author’s own

Author’s own mage

Author’s own

image

Author’s own image

T4A 58% PAE, 0.25 W Pout

3-5 Watts at

Ka-band

0.5-1 Watt at

W-band

T3 GaN device chiplets for

heterogeneous integration of

RF ICs

Ka-band

On-going improvements:

increase in Ka-band

efficiency & power

• Perform Multi-Project-Wafer (MPW) foundry runs for external designers

MECAMIC Heterogeneous Integration

RF in

RF out

MECAMIC

Interconnect

Goal – Achieve high power & high efficiency

at mm-wave to enabling high-power arrays

& with reduced cooling

Tape-out access available

to external customers

through MPW model