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June 2012 77 1527-3342/12/$31.00©2012 IEEE
Eliot D. Cohen is the president of EBCO Technology Advising Inc., 11312 Freas Drive, North Potomac, MD 20878 USA.
Digital Object Identifier 10.1109/MMM.2012.2189989
Date of publication: 7 May 2012
Eliot D. Cohen
It has now been more
than a quarter of a
century since the
U.S. Department of
Defense (DoD) began
its microwave and millimeter-wave mono-
lithic integrated circuits (MIMIC) program. Dur-
ing that time, the Cold War ended and, as a result,
there was a dramatic consolidation of defense companies.
Many engineers, scientists, and others who participated in
the program have changed companies, changed jobs, retired and,
in some cases, died. The legacy of the program, however, remains:
the establishment of the capabilities, infrastructure, and knowledge nec-
essary to design and produce GaAs MMICs for nearly any application with
high yield, at low cost, and possessing the specific performance and reliability
characteristics required for their use in a huge number of system applications, both
military and commercial [1]–[3]. This, in turn, has resulted in the United States’ becom-
ing the world leader in GaAs MMIC technology, a position that it still holds. The program
played a major role in disproving the once popular statement that “GaAs is the material of the
future and always will be.” This article describes the beginnings of the program and the strategy
it used to achieve its goals. It also summarizes what has been accomplished and offers some advice
ANNIVERSARY
ISSUE FEATURE—
Historical Perspective
© PHOTODISC
78 June 2012
based on the experience gained over the course of the
program.
What Came BeforeBeginning in the 1970s, a number of companies began
producing GaAs MMICs with performance levels
high enough to generate interest and excitement in the
microwave industry. In particular, Plessey, Raytheon,
Texas Instruments (TI), and others all produced MMIC
amplifiers that, at the time, achieved record-setting
performance levels. Successful R&D results continued
to be reported during the 1980s by many engineers and
organizations. In 1978, for example, one-stage power
amplifiers were considered state-of-the-art MMIC cir-
cuits; by 1986, a complete transmit-and-receive (T/R)
module had been produced on a single chip. Figure 1
shows an early MMIC T/R module chip.
However, the yield of functioning MMICs was typi-
cally quite low because GaAs material characteristics
were highly variable; computer-aided design (CAD)
capabilities were very limited; circuit fabrication was
carried out in laboratories, rather than on production
lines, and typically on wafers of very small diameter
or even on pieces of wafers; there were few attractive
packaging options; and automated testing capabili-
ties were limited to the lower range of the microwave
frequency spectrum. Most microwave and millime-
ter-wave solid-state circuits during that period were
“hybrids,” i.e., they used individual devices such as
GaAs FETs, silicon bipolar transistors, and IMPATTs
that were attached with wire bonds to various types
of microwave circuit boards or mounted in waveguide
structures. As one might expect, these circuits were
relatively expensive. The variability of circuit parasitics
associated with the use of wire bonds resulted in high
levels of unit-to-unit performance variance. Wire bonds
were also a principal cause of reliability problems.
At the time, commercial applications of GaAs
microwave devices were extremely limited. This made
it financially unattractive for industrial companies to
invest the large amounts of money required to create
the capabilities and facilities required to produce GaAs
MMICs with sufficiently high yield and acceptable
2-in Wafer Photograph
Single Chip T/R Module
Microwave Technology and Products
Wafer Yield History d.c. (Probe)
Wafer # Good Chips Yield (%)
553252121165
1H5-302 (11)H5-302 (16)H5-302 (19)H5-302 (20)H5-270 (7)H5-270 (10)H5-270 (11)H5-270 (12)
Total Wafers Run 1457%19
Wafer YieldChips per WaferChip Yield
Overall Yield 8%
Defense Systems and Electronics Group
Microwave Performance (5 Chip Average)
14%
614431
1
Chip Complexity
• 25 FETs with 20.4 mm Total Gate Width
• 43 Capacitors with 377 pF Total
Capacitance
• 24 Resistors, 48 Substrate Vias
• Chip area 58.6 mm2 (90,800 mil2)
• Transmit Channel
• Receive Channel
– Gain
– Gain
17.2 dB
13.5 dB5.1 dB
420 mW11.7%
– Output Power
– Noise Figure
– Efficiency
Figure 1. An early MMIC T/R module chip.
Beginning in the 1970s, a number of companies began producing GaAs MMICs with performance levels high enough to generate interest and excitement in the microwave industry.
June 2012 79
per-unit costs for either military or commercial appli-
cations. DoD officials recognized that it was essential
for the DoD to provide sufficient funding to bring
monolithic microwave and millimeter-wave technol-
ogy to fruition. When it became evident that numer-
ous military systems used for missile guidance, radars,
electronic countermeasures, and communications
could not achieve the required unit-to-unit unifor-
mity of acceptable performance, demonstrate reliable
operation over long periods of time, and meet accept-
able cost targets with the use of hybrid GaAs device
technology.
The Beginning of the MIMIC ProgramAlthough I served as MIMIC Program director for most
of the program’s duration, the first program director
was E. D. (Sonny) Maynard Jr. Maynard was respon-
sible for developing the selected overall program
framework and securing a budget for the program
that was adequate to accomplish what was needed to
bring MMIC technology to fruition. In the beginning,
it was not clear how the various components of the
DoD would be involved in planning and executing this
major effort or exactly what level of funding would be
provided. As one might expect, a number of propos-
als were put forth concerning how the program should
be structured and managed, since all of the military
services had considerable interest in the development
and use of microwave monolithic technology. May-
nard, who at the time was Director of Computer and
Electronics Technology in the Office of the Secretary of
Defense, produced the winning program proposal, and
on 30 December 1985, Donald A. Hicks, the Undersecre-
tary of Defense, established the MIMIC Program Office.
Maynard was named the first MIMIC Program Direc-
tor and was vested with the responsibility for working
with the Army, Navy, and Air Force to assure that their
MMIC requirements would be met. After considerable
study, a budget of approximately US$570 million was
approved for the overall program. Thus the MIMIC
Program was born.
During mid-1985, Maynard contacted me and
requested that I assist him in preparing the technical
plan for this new effort. Early in 1986, the position of
Deputy Director of Microwave and Millimeter-wave
Programs was established in the DoD Technology
Analysis Office, under Maynard’s supervision. I was
appointed to this position on 20 April 1986 and given
the responsibility for serving as manager of the MIMIC
Program. In August 1987, Ms. Elissa (Lisa) Sobolewski
joined the program and, after the program was trans-
ferred to the Defense Advanced Research Projects
Agency (DARPA), subsequently became responsible
for managing the numerous programs conducted as
part of MIMIC Phase 3.
Maynard introduced the MIMIC Program to the
microwave community (and the world) on 4 June 1986
at that year’s IEEE Microwave and Millimeter-Wave
Monolithic Circuits Symposium, held in Baltimore,
Maryland [4].
Transition to DARPAEarly in 1988, senior DoD managers made the decision
that major programs should not be conducted within
the Office of the Secretary of Defense, since it was also
charged with oversight of those programs. As a result,
in late 1988, responsibility for the MIMIC Program,
along with several other major DoD efforts, was trans-
ferred to DARPA. The rationale for selection of DARPA
as the new home for the program was that it was a
so-called “purple suit” agency that was not under the
direction of any of the individual services but could
take responsibility for R&D efforts that would benefit
all of them. Maynard left government service at that
time, and Craig I. Fields, Deputy Director of DARPA
for Research, appointed me to the position of Director
of the MIMIC Program, with overall responsibility for
its management, technical strategy, and execution.
MIMIC Program StructureThe MIMIC Program adopted a management structure
similar to that used by one of its predecessors, the Very
High-Speed Integrated Circuits (VHSIC) Program. The
VHSIC Program (operational from 1980 to 1990) was
aimed at developing two new generations of silicon
digital IC technology. The MIMIC management struc-
ture consisted of a MIMIC Program Office within each
of the Services—Army, Navy, and Air Force—headed
by a Service Program Director and staffed by person-
nel from that service. The initial Army MIMIC Director
was C.G. Thornton. He was succeeded by V.G. (Walt)
Gelnovatch, who initially served as the Army’s Dep-
uty MIMIC Director. The initial Navy MIMIC Director
was Daniel McCoy, who was succeeded by Charles D.
(Chuck) Caposell. Gerald Borsuk served as the Navy’s
Deputy MIMIC Director. The Air Force’s MIMIC Direc-
tor throughout the program was William Edwards.
Robert T. (Tim) Kemerley and Steve Kiss served as the
Air Force’s Deputy MIMIC Directors.
Each Service’s Program Director was respon-
sible for providing input to the MIMIC Program
Director concerning the needs of his service and
recommendations about how these needs could be
met. They also provided suggestions and recommen-
dations concerning what should be included in the
The MIMIC Program adopted a management structure similar to that used by the Very High-Speed Integrated Circuits (VHSIC) Program.
80 June 2012
statements of work for each phase of the program,
led their service’s teams during proposal evaluations,
and provided input as to which proposals should be
selected. Regular steering committee meetings were
held every few weeks, chaired by the MIMIC Director
and attended by the Service Program Directors and
Deputy Directors, to discuss their needs, assess the
program’s progress, and resolve any problems. They
and their staff members provided invaluable services
to the overall program by assuring that program con-
tracts were awarded in a timely manner, providing
day-to-day oversight of contractor activities, oversee-
ing evaluation of various deliverable items produced
during the program, providing information to system
program managers within their Services about the
MIMIC Program, and encouraging the use of MMIC
technology in Army, Navy, and Air Force systems.
There were well over 100 people throughout the DoD
who contributed their time and efforts to the MIMIC
Program, and they helped immeasurably to make the
program a success. In addition to the DARPA and
Service personnel, two outstanding consultants—
Robert Bierig and Albert Brodzinsky—contributed
invaluable insight, recommendations, and support
throughout the program. The contributions made by
the microwave contractor community were remark-
able and, of course, they played the key role in assur-
ing that the program achieved its goals.
As was the case for the VHSIC Program, the MIMIC
Program was divided into several phases. Phase 0,
the program definition phase, was conducted during
1986 and 1987. It gave selected contractors (virtually
the entire U.S. microwave community) the opportu-
nity to study and submit their recommendations as
to how best to meet the program’s goals and require-
ments. Sixteen industrial teams, including a total of 48
participating companies, were selected to participate
in this phase. These teams studied the potential use
of MMICs in more than 50 system applications and,
in their final reports, submitted recommendations
for device and circuit approaches, design and manu-
facturing facilities, material improvement, test strate-
gies, and foundry selection and capabilities. Phase 1,
the first of two development phases, was conducted
between 1988 and 1991 by four contractor teams. The
companies heading the teams were Raytheon and TI,
which formed a formal joint venture to carry out their
program responsibilities (team members were Aero-
jet, Airtron, Compact Software, Consilium, General
Dynamics, Magnavox, Norden, and Teledyne); TRW,
now Northrop Grumman Aerospace Systems (team
members were General Dynamics, Hittite, and Honey-
well); General Electric/Hughes (team members were
AT&T, Cascade Microtech, EEsof, E-Systems, Harris
Microwave, Hercules, and M/A COM); and ITT/Mar-
tin Marietta, which also formed a formal joint ven-
ture (team members were Alpha, Harris Government
Systems, Pacific Monolithics and Watkins-Johnson).
Phase 1 was directed toward establishing many of the
necessary capabilities and the infrastructure for meet-
ing the program’s overall goals.
Phase 2, the second of the development phases,
began in 1991 and continued until the conclusion of
the program in 1995. It was conducted by three teams
headed by Raytheon/TI (team members were Aerojet,
Airtron, Consilium, General Dynamics, Hittite, Lock-
heed-Sanders, and Teledyne), Hughes (team members
were Alliant Techsystems, Cascade Microtech, EEsof,
ITT, Litton, M/A-COM, Martin Marietta, and Rock-
well), and TRW (team members were Alliant Techsys-
tems, Comsat, Hercules, Northrop, and Westinghouse).
During this phase, the work begun in Phase 1 con-
tinued, with increasing emphasis on higher levels of
chip performance, reduction of the minimum feature
sizes of devices, realizing high levels of performance
at frequencies up to 94 GHz, extending the capabili-
ties of test equipment, assessing MMIC reliability,
and promoting insertion of MMIC technology into
military systems. There were two MMIC development
tracks during Phase 2: the first was aimed at assuring
a very robust base for MMIC technology, making use
of device types and feature sizes developed during
Phase 1, while the second was a higher-risk set of tasks
directed toward the development of a new generation
of higher-performance MMICs.
Phase 3 of the program afforded the opportunity for
important but smaller efforts to be pursued in parallel
with Phases 1 and 2 by various contractors, including
Avantek, Ball, Cascade Microtech, Compact Software,
M/A-COM, Motorola, North Carolina State University,
Scientific Atlanta, Sonnet Software, TriQuint, Univer-
sity of California at San Diego, University of Colorado,
University of Illinois, and Varian.
Program StrategyThe overall objective of the MIMIC Program remained
invariant throughout. It was “to develop micro-
wave/millimeter-wave subsystems for use in mili-
tary weapon system ‘front ends’ that are affordable,
available, and broadly applicable.” The program was
directed toward the acceleration of development, man-
ufacturing, and demonstration of affordable micro-
wave and millimeter-wave analog ICs and promoting
the use of MMICs in all systems where benefits could
be gained.
The strategy adopted to meet these overall goals
involved putting into place a comprehensive program
that was aimed at improving capabilities in every
technical area considered critical for meeting the pro-
gram’s objectives. Affordable manufacturing was a pri-
mary consideration, and all contractors were strongly
encouraged throughout the program to assign a high
priority to this requirement. Emphasis was placed on
putting into place the design, fabrication, packaging,
June 2012 81
and test capabilities and tools that would allow the
realization of MMICs that would provide performance,
reliability, and cost benefits for any system (consistent,
of course, with the laws of physics) rather than focus-
ing on producing sets of generic MMICs that did not
necessarily meet the specific needs of the systems they
were intended for. In order to demonstrate the value
of MMIC technology, every MIMIC contractor team
was required to select at least one radar, electronic
countermeasures, communications, or smart weapon
system of importance to the DoD, identify the issues
and problems of this system (or systems) that could be
addressed by use of MMIC technology, and lay out the
course of action it would follow to realize the advan-
tages of MMIC use in system applications. Brassboards
for each system were designed and produced over the
course of the program to demonstrate the success of
the contractor’s approach.
Major efforts undertaken to ensure successful sys-
tem implementation were focused on making signifi-
cant advances in bulk GaAs boule quality and size. In
addition, considerable effort was expended to improve
capabilities for GaAs active-layer growth. Ion implan-
tation, chemical vapor deposition, and molecular beam
epitaxy (MBE) were all used for active-layer formation.
Advanced CAD capabilities and accurate device and
circuit models were established, as were “production-
level” fabrication capabilities that made use of sta-
tistical process controls to improve chip yields. The
state-of-the-art of microwave and millimeter-wave
MMICs continued to advance through research and
development activities. Automated on-wafer testing
capabilities that could provide accurate measure-
ments at frequencies up to 110 GHz were designed
and installed. Finally, packages that would not com-
promise either the performance or reliability of the
MMICs they housed were produced and put into use.
Techniques first developed by the silicon digital IC
industry were adopted. These included determination
of parameters critical for high-performance operation,
gathering and processing of large amounts of data
during MMIC fabrication and evaluation for use in
establishing statistics-based process controls, estab-
lishment of upper and lower limits for the values of the
parameters considered important, use of Pareto charts
to determine and eliminate yield inhibitors, and feed-
back of microwave (and millimeter-wave) test data to
refine the recipes for the MMICs being fabricated and
improve model accuracy. Each contractor team was
required to put into place an automated process con-
trol system database that tied together price and cost
models, process control, CAD, computer-aided testing
(CAT), computer-aided manufacture (CAM), and envi-
ronmental considerations.
Throughout the program, each team was also
required to periodically submit a business plan that
described its strategy to affordably manufacture and
insert MIMIC program hardware into systems. The
plan also included projected sales and the progress of
efforts to make use of MMICs in systems. The objective
of requiring business plans was to assure that every
participating contractor focused on interacting with
DoD systems personnel on a regular basis to make
sure they were informed of what MMIC capabilities
were available to them and to determine how best to
meet their system needs. Development for commer-
cial applications of the technology was also strongly
encouraged. Great emphasis was placed on continuous
yield improvement and cost reduction of the MMICs
being produced. This goal was achieved by com-
paction of the circuitry on each chip so that smaller
amounts of GaAs area were needed to produce MMICs
with increasing circuit complexity and capabilities.
Near the conclusion of the program, the Phase 2 con-
tractor teams were required to perform a validation
procedure to demonstrate that their fabrication capa-
bilities were sufficient to repeatedly produce wafers of
MMICs with an acceptable yield, leading to acceptable
unit chip costs. They were also strongly encouraged
to establish and maintain “foundry” services so that
other contractors, who did not have in-house MMIC
fabrication capabilities, could make use of the wafer-
processing capabilities developed under the program.
The focus on high yield and low cost led to the viabil-
ity of using MMICs in commercial applications, most
notably as power amplifiers for cellular telephones.
Establishment of commercial applications has done
much to sustain the production capabilities developed
during the program.
Progress over the Course of the ProgramFor people just beginning their careers in the micro-
wave industry, it may be hard to imagine the state
of MMIC capabilities less than 25 years ago. In 1988,
many GaAs devices and circuits were being fabri-
cated on 3-in-diameter wafers grown using high- or
low-pressure Czochralski processes, with some 2-in
material still being used [5]. Boules were quite small,
material characteristics were highly variable, and
predictors of which material properties would result
in superior RF performance had not yet been firmly
established. Typically, companies received GaAs
substrates grown as “best efforts” by material ven-
dors and then conducted their own evaluations in an
attempt to identify acceptable material. At the time,
the best GaAs substrates were produced by Japanese
companies. (During the first years of the MIMIC Pro-
gram, however, three U.S. companies began producing
high-quality GaAs substrates. Although only a small
amount of program funding was devoted to GaAs
substrate development, the program’s existence served
as a catalyst that encouraged U.S. companies to make
the necessary investments to produce high-quality
GaAs substrates.) Also, at the program’s start, there
82 June 2012
were no nondestructive evaluation techniques that
yielded accurate information about which substrates
were “good” or “bad.” Most substrates had high levels
of etch pit densities, indicative of substantial crystal-
line imperfections and high and variable amounts of
unwanted impurities. There were spirited discussions
concerning which material properties were important
for determining microwave device and MMIC perfor-
mance, but no definitive answers existed. Processing
was done in R&D laboratories, typically using wet-
etching techniques and optical lithography, although
some use was being made of electron-beam lithog-
raphy. Low yield, nonexistent process control, and a
lack of manufacturing discipline characterized the
status of MMIC fabrication capabilities in the early
and mid-1980s.
A major contribution of the MIMIC Program to
advancing GaAs MMIC technology was the stabili-
zation of fabrication processes and the accumulation
of sufficient statistical process control data to per-
mit accurate identification of the sources of process
variability. Accumulation of the requisite database
required a high throughput of GaAs wafers using a
nominally unchanging fabrication “recipe.” The rela-
tively large wafer throughput, data accumulation and
analysis, and subsequent continuous corrective actions
undertaken led to the achievement of wafer fabrication
process integrity. This, in turn, provided the ability to
repeatably produce MMIC circuits with predictable
performance at a cost acceptable to military system
program offices.
By 1988 there were a number of individual CAD
tools available, approximate models were available for
some linear circuits, and there were some design verifi-
cation capabilities. No integrated microwave CAD sys-
tem yet existed, however; there was a lack of accurate
models for nonlinear circuits and for all millimeter-
wave devices and circuits, and there were very limited
performance simulation capabilities. MESFETs with
gate lengths of 0.5 µm or greater were available, and
ones with smaller gate lengths as well as some HBTs
and HEMTs had been demonstrated. The HEMT and
HBT technologies were very immature, however. The
reliability of these devices had not been verified, and
most power devices had relatively low power-added
efficiency. There were many individual types of cir-
cuit housings available. Most were custom-fabricated
from machined aluminum, but they were expensive,
required large amounts of manual assembly, and often
degraded performance, particularly at higher frequen-
cies of operation. Wafer-level small-signal perfor-
mance evaluation equipment was becoming available
for use at frequencies up to 26.5 GHz, but there was
limited automation and a lack of capability for wafer-
level testing of power devices.
By 1991, near the conclusion of Phase 1 of the pro-
gram, considerable progress had been made toward
establishing the necessary capabilities to mass-produce
MMICs with reasonable yields and relatively uniform
performance characteristics. High-quality 3-in-diam-
eter GaAs wafers with uniform characteristics had
become available from U.S. vendors; new design work-
stations had been developed and were being offered
for sale; contractors had put into place high-rate MMIC
processing capabilities; major advances in lithogra-
phy had been achieved; new types of circuit housings,
including ones fabricated from ceramic and metal
matrix materials, were becoming available, with pro-
jected costs of a few dollars each; and on-wafer test-
ing capabilities had significantly advanced. In parallel,
as part of Phase 3, on-wafer pulse power testing sta-
tions had been produced, and by September 1990 the
first 50–75-GHz wafer probe system was being offered
for sale by Cascade Microtech [6]. The time needed
for evaluation of a chip’s S-parameters, noise figure,
IP3, and other performance characteristics had been
decreased, through the use of on-wafer testing instead
of in-fixture testing, from several minutes to fractions
of a minute. On-wafer testing also afforded large cost
savings. For example, one contractor reduced testing
costs of a 2-W Ku-band power amplifier from US$107
per chip to US$2.37 per chip using on-wafer testing
rather than in-fixture testing.
Other Phase 3 programs were focused on improve-
ment of metal–organic chemical vapor deposition
(MOCVD) and MBE growth techniques, CAD mod-
els and tools, advanced multichip ceramic packages,
and development of a MIMIC Hardware Description
Language. Statistical process controls and design
centering were being used to improve yield and cir-
cuit performance. At least one company had incorpo-
rated a voice recognition system linked to an Oracle
database for operators to use during visual inspec-
tion of MMIC die MMIC GaAs FET X-band ampli-
fiers had been fabricated by the GE/Hughes team
that produced a minimum power output of 2 W with
30% minimum power-added efficiency over the band
from 7.5–11 GHz and had a minimum power gain of
11 dB. Wide-band amplifiers had also been produced
with power-added efficiency of approximately 20%.
A W-band amplifier chip had been realized by TRW
that made use of a pseudomorphic InGaAs HEMT
with a 0.1-µm T-gate. It had a gain of more than 13 dB
and a noise figure of 5.5 dB at 94 GHz. In addition, a
16-function transceiver chip had been developed by
the ITT/Martin-Marietta team that operated from 5–6
GHz with a receive mode noise figure of 4 dB, gain
flatness of !1.5 dB, and receiver gain of 22 dB. In its
transmit mode, it provided 3.5 W of output power with
42 dB of gain and 40% power-added efficiency. Scores
of other MMIC chip types were produced, including
phase shifters, low-noise amplifiers, power ampli-
fiers, T/R switches, voltage-controlled oscillators,
down-converters, and tuners. In many cases, multiple
June 2012 83
functions were performed using a single MMIC chip.
Frequency ranges addressed were from C-band to
W-band. The first insertion of MMIC technology into
a military system occurred near the beginning of the
program: MMICs were used in the Navy’s High-Speed
Anti-Radiation missile (HARM), produced by TI [7].
Figure 2 describes the HARM MIMIC insertion and
shows a photograph of the IF amplifier used in this
system. Numerous demonstrations of potential MMIC
use in other military systems had also been carried out
by the end of Phase 1 for systems such as an Advanced
Medium-Range Air-To-Air Missile (AMRAAM), Sense
and Destroy Armor (SADARM), GEN-X (an expend-
able missile terminal guidance phase decoy) [8], [9],
and the Multi-Option Fuze for Artillery (MOFA) [3],
[10], [11]. Figure 3 describes the GEN-X insertion and
shows a picture of the MMIC module that was used.
MOFA made use of an FM CW radar transceiver on a
chip that cost only a few dollars. It replaced ten fuze
types previously used by the Army. Low cost was an
essential requirement imposed by the MOFA program
manager, and this objective was achieved.
In general, MMIC chip costs were being steadily
reduced by significant amounts. At the beginning
of the program, for example, the Raytheon/TI team
established a cost metric of U.S. dollars per square mil-
limeter of GaAs. This became widely used as a figure
of merit by many of the program’s participants. The
estimated chip cost of an X-band power amplifier at
the beginning of Phase 0 of the program was approxi-
mately US$20/mm2. By the middle of Phase 1, TI was
producing X-band power amplifiers on its production
line at a cost of US$3.24/mm2 and low-noise amplifiers
for US$2.67/mm2.
By 1994, near the conclusion of Phase 2 of the MIMIC
Program, a solid infrastructure had been established
for MMIC technology [12]. U.S substrate vendors had
become profitable and were selling GaAs material
worldwide. Two U.S. CAD vendors were profitable and
dominated the world market for microwave CAD. RF
test equipment developed under Phase 3 of the MIMIC
Program included wafer probe equipment from Cas-
cade Microtech that provided accurate parameter mea-
surements at frequencies up to 110 GHz and defined
the state of the art. Several package vendors were avail-
able to support the MMIC industry. GaAs boule sizes
had increased substantially, with typical boules yield-
ing greater than 100 substrates. Wafers with diameters
of 4 in were readily available, and some 6-in-diameter
wafers were being produced. Wafer characteristics
and uniformity had greatly improved, and several
participating companies were offering foundry ser-
vices to provide MMICs to other organizations. The
program also helped to establish commercial supplies
of prequalified, production-grade epitaxial material.
This was particularly important for the fabrication of
HEMTs and HBTs. Many types of MMICs, for both
power and low-noise applications, were routinely being
produced with reasonably high yield. These MMICs
operated at frequencies from UHF to as high as 94 GHz.
The Raytheon/Texas Instruments MIMIC Joint Venture Raytheon
MIMIC Insertionin
High-Speed Anti-RadiationMissile
AGM-88AApplication/Benefit
• Passive Radar Homing Missile Uses Broadband Monopulse Seeker for Precision Guidance• Two IF Amplifier Pairs (Four Amplifier Modules) Provide Sum and Delta Signal Conditioning• MMIC Insertion Provides Approximately x2 Cost Reduction
• Major Insertion Milestones
• Production Volume
– Module Level Qualification Completed 10/88– System Level Validation Complete 1/89– System Insertion Initiated 1/89
– 150 Systems/Month for Next Five to Six Years– With Two MMICs/Amplifier, 1,200 Yielded MMICs Required Per Month
Aerojet Airtron Compact Consilium General Dynamics Magnavox Norden Teledyne
• Insertion/Status
AGM-88A Launched From F/A-18C
Broadband IF AmplifierMMIC (0.5-4.0 GHz)
Figure 2. MMIC insertion of IF amplifier into Navy’s HARM system.
84 June 2012
They included power MESFETs produced using base-
line processes that had 0.4-µm gate lengths, low-noise
HEMTs with gate lengths of 0.2 µm, and power HBTs
with emitter widths as small as 3 µm. Under the
advanced device technology portion of the program,
GaAs power and low-noise HEMTs were realized with
gate lengths of 0.1 µm, and power HBTs were fabricated
with emitter widths as small as 2 µm. Companies had
made major advances in making chips more compact to
reduce their cost. A notable example was a M/A-COM
MESFET X-band low-noise amplifier. Its size had been
reduced to 25% of its original area, and improved per-
formance was achieved as well. This resulted in a cost
reduction from US$80 to US$13.50 per chip. TI reported
that its cost target of US$1/mm2 had been achieved
for X-band low-noise amplifier chips produced in rela-
tively high quantities. PHEMT power amplifiers with
0.25-µm gate lengths had been produced by multiple
companies. One of these achieved a power output of
2–3 W with power-added efficiency of 15–20% over the
frequency range from 6–18 GHz. TI had demonstrated
a 10-W, 239% power-added-efficiency, 8.5–10 GHz HBT
power amplifier. A particularly exciting MMIC was a
2–20-GHz frequency synthesizer designed and fabri-
cated by Northrop using 0.15-µm-gate-length HEMTs
on a single 3.7-by-4.1-mm2 chip. This chip combined 35
functions. Fully functional chips were realized during
the first pass, with a 56% RF yield on a tested wafer.
Work continued on C-band frequency-modulated con-
tinuous-wave (FMCW) radar chips costing less than
US$10 each. This led to a factor-of-eight reduction in dc
power and a 50% reduction in chip area compared with
a previous version. TRW was able to realize W-band
LNAs and 50–100-mw W-band power amplifiers with
6 dB of gain and 8.5% power-added efficiency. The
W-band LNAs were used in millimeter-wave cameras
to provide improved visibility through smoke and fog
over that available using infrared sensors [13]. Figure 4
is a photo of a three-stage W-band LNA developed by
TRW during Phase 2 of the MIMIC Program; Figure 5
shows a collection of W-band MMICs developed by
TRW during the MIMIC Program; and Figure 6 pro-
vides photos and information about the millimeter-
wave camera developed by TRW using technology
from the MIMIC Program.
As a result of the advances made during the pro-
gram, MMICs were being used in increasing numbers
in both military and commercial systems. The first
demonstration of MMICs from the program in a solid-
state phased array was in the Counter-Battery Radar
(COBRA) system. Later, the production of the first large-
scale phased array [Raytheon’s Ground-Based Radar
(GBR) system] that used MMICs was a direct result
of the technology advancement and chips developed
under the MIMIC Program. Figure 7 shows a GBR sys-
tem MMIC module. The deciding factors that mitigated
in favor of using modules populated with GaAs MMICs
in this system were both performance- and cost-related.
The Raytheon/Texas Instruments MIMIC Joint Venture
Gen-X Decoy
Application
Insertion Status
Raytheon
• Missile Terminal Guidance Phase Decoy
• Program in FSED and Tech Eval Completed with 65 Successes out of 69 Trials
• Op Eval Including Live Firings was 100% Successful
• More Than 9,200 MMICs of 12 Circuit Types Supplied in Units to Date
• Initilal Production Order is Planned for Release in May 1992. Full Production Could Involve Several Hundred Thousand Units
Aerojet
Module
Assembled Decoy
Airton Consilium General Dynamics Hittite Lockheed Sanders Teledyne
• Deployed from Standard Navy Chaff/Flare Dispenser (Size: 1.3 in Diameter, 6 in Long)
• Size and Cost Constraints Dictate MMIC Insertion
Figure 3. Insertion of MMICs into the Navy’s GEN-X Decoy developed by TI.
June 2012 85
Yield improvements and technology advances result-
ing in dramatic cost reductions also led to the nearly
universal use of MMICs as power amplifiers in cellu-
lar telephones [14], [15]. GaAs MMICs were and still
are used in satellite communication systems, includ-
ing iridium, and in some automotive collision avoid-
ance radar systems [16]. During the program, Hughes
Aircraft developed X-band radar chips that were pro-
duced in the same MMIC foundries that fabricate chips
for military applications. These were used in a system
called Forewarn that let school bus drivers become
aware of the presence of children within the “blind”
areas surrounding buses.
More Recent ProgramsMany of the capabilities and technical approaches devel-
oped under the MIMIC Program have continued to
be used in subsequent programs, including DARPA’s
Microwave and Analog Front-End Technology (MAFET)
program. MAFET was conducted between 1995 and 2000
and resulted in further advances in GaAs HEMT and
HBT technology as well as the realization of high-perfor-
mance indium phosphide (InP) MMICs, principally for
use at millimeter-wave frequencies. More recently, DAR-
PA’s Wide-Band-Gap Semiconductors for RF (WBGS-RF)
program, focused on development of GaN MMICs that
provide higher power output per unit area and more
robust performance at high operating temperatures than
GaAs MMICs, has also benefited from the experience,
fabrication capabilities, CAD, packaging, and testing
advances that resulted from the MIMIC Program.
Some Observations and AdviceAny program whose goal is to transition technology
from an embryonic stage to maturity will be expensive.
Before undertaking such a program, the following
questions should be asked:
• Are significant benefits likely to result from this
technology or product?
• Is it enabling? For example, will it make a sig-
nificant difference in system performance, cost,
weight, volume, or reliability?
• Is the cost of developing and marketing it com-
mensurate with the benefits it will provide?
• Will the program result in its “customers” receiv-
ing what they want and need?
As the program progresses, the following addi-
tional factors should be evaluated on a periodic basis:
• Is the product or technology ready for use?
• Does it still offer compelling advantages versus
its competition?
• Is its price right?
• Is it readily available?
• Is it reliable?
• Does it meet customer needs?
One approach that should be avoided is using avail-
able resources to fund a large number of small, unre-
lated efforts. Programs of various sizes and durations
W-Band Monolithic 3-Stage InGaAs HEMT LNA
Performance
Key Features
0.1μm T-gate
25
20
15
Gai
n (d
B)
Noi
se F
igur
e (d
B)
10
5
091 92 93 94
Frequency (GHz)
N.F. (dB)
Gain (dB)
Goals
95 96 97
PM InGaAs HEMT on GaAs
Chip Size: 1.2 × 3.2 mm
3.5 dB Noise Figure
21 dB Associated Gain
91–97 GHz
2523
46-9
1
Figure 4. A three-stage W-band LNA developed by TRW during Phase 2 of the MIMIC Program. (Photo courtesy of Northrop Grumman Aerospace Systems.)
86 June 2012
are completely acceptable and desirable, but strong
emphasis must be placed on making use of the results
from all efforts, large and small, to meet overall program
objectives. From its beginning, the MIMIC Program was
focused on comprehensively addressing every aspect of
MMIC development considered critical for achieving
success in establishing the necessary MMIC design, fab-
rication, packaging, and testing capabilities. To ensure
that this strategy could be successfully carried out, the
DoD provided the program with both an adequate bud-
get and a sufficient period of time in which to achieve
success. There is no question that sufficient financial
TRW’s W-Band MMICs
Low Noise Amplifiers
Two-Stage LNA
Single-Stage LNA
Performance PerformancePerformance
Performance
PerformancePerformance
Performance
Performance
Performance
2449
36-9
0
2449
41-9
0
Single-Balance Diode Mixer
Voltage Controlled Oscillator Power AmplifierE
MP
I 100
0
Monolithic Image-Reject Mixer W-Band Downconverter
Three-Stage LNA
100 mW Power Amplifier
2449
40-9
0
Mixers/Downconverters
VCOS/Power Amplifers
• 3.5 dB Noise Figure• 5.3 dB Associated Gain• 1.35 × 1.2 MM2
• 7.6 dB Conversion Loss• 10 dBm LO Power• >20 dB RF-LO Isolation• 90–98 GHz RF/LO Frequency
• 10 dB Conversion Loss• 10 dB LO Power• >12 dB Image Frequency Rejection• <12 dB Noise Figure at 100 MHz IF• 1.6 × 2.0 mm2
• 8.8 dBm Output Power• 14% Conversion Efficiency• 1.6 × 2.1 mm
• 17.9 dBm Output Power• 6.5 dB Gain• 8.5% Power Added Efficiency• 320 μm Output Stage• 2.3 × 3.2 mm2
• 6.5 dBm Noise Figure• 5.5 dB Conversion Gain• 0.02–8 GHz IF• 1.0 × 4.0 mm2
• 3.5 dBm Noise Figure• 21 dB Associated Gain• 1.2 × 3.2 mm2
• 4.6 dBm Noise Figure• 13.7 dB Associated Gain• 2.24 × 1.2 mm2
• 19.8 dBm Output Power• 6 dB Gain• 320 μm Output Stage• 3.5 × 4.2 mm2
Figure 5. A collection of W-band MMICs developed by TRW during the MIMIC Program. (Photo courtesy of Northrop Grumman Aerospace Systems.)
June 2012 87
resources are absolutely essential for transitioning any
technology from research status to production readi-
ness. For example, the budget of the MIMIC Program
allowed for the production of thousands of wafers over
its lifetime, making it possible to gather sufficient statis-
tical information to eliminate yield inhibitors, make use
of statistical process control, establish design centering,
greatly improve chip yield, and drive costs down to the
point where MMICs could be used in both military and
commercial applications. This, in turn led to further ben-
efits because it became economically feasible for indus-
trial corporations to invest more of their own funds to
improve production, design, and testing capabilities. In
addition, having some discretionary funding permit-
ted new, promising efforts to be pursued rapidly and
allowed the results of these efforts to be incorporated
into mainstream program activities. It also increased
the incentive for companies to assign the “best and the
brightest” people to the program and assign the high-
est priority to designing and fabricating the program’s
hardware. Finally, it provided funding to overcome the
unforeseen problems that arose from time to time.
There were a number of other factors related to
the MIMIC Program that, in my opinion, contributed
greatly to its success. Although for most of its life the
program was carried out under DARPA sponsorship,
Army, Navy, and Air Force personnel were heavily
involved from beginning to end and contributed greatly
to the success achieved. Their involvement made pos-
sible continuing fruitful interactions between Service
MIMIC Program personnel and Service and industry
system program offices. As a result, managers charged
with the development and fielding of major electronic
systems were kept informed of program accomplish-
ments and encouraged to make use of MMIC technol-
ogy. Many of them did so. In addition, Service laboratory
personnel contributed their technical expertise on a
day-to-day basis during interactions with program
contractors: they attended program reviews and steer-
ing group meetings, carried out measurements, evalu-
ated hardware and software that was produced by the
various program contractors, and performed reliability
assessments of MMIC chips. The National Institute of
Standards and Technology (NIST) also contributed sig-
nificantly to the program by establishing measurement
standards for use in evaluating program deliverables.
PMMW Camera Uses TRW’S Unique W-Band MMIC Technology
GaAs MMICReceiver (2 × 7 mm2)
1 × 4 Receivers Module
1 × 40 ReceiversCard FPA with 1,040 Receivers
Camera Technical Data
• 15° × 10° Field of View with 18′′ Lens Aperture• Center Frequency 89 GHz with 10 GHz BW (from 84 to 94 GHz)• Minimum Resolvable Temperature = 2K in the Scene• 17 Hz Scene Refresh Rate and 30 Hz Display Rate
GaAs MMICReceiver (2 × 7 mm2)
1 × 4 Receivers Module
1 × 40 ReceiversCard FPA with 1,040 Receivers
Camera Technical Data
• 15° × 10° Field of View with 18′′ Lens Aperture
Figure 6. A passive millimeter-wave camera developed by TRW using technology from the MIMIC Program. (Photo courtesy of Northrop Grumman Aerospace Systems.)
Figure 7. A GBR system MMIC module.
88 June 2012
A remarkable degree of cooperation existed among
government personnel from various agencies and
between them and the program’s contractor partici-
pants. Even more impressive was the degree of cooper-
ation among virtually all of the contractor participants.
This helped immeasurably to overcome the many tech-
nical challenges that presented themselves throughout
the program. A particularly unusual event was the for-
mation of formal legal joint ventures between Raytheon
and TI and between ITT and Martin Marietta. Hughes
and GE also worked closely with each other. I believe
that one of the principal reasons for the program’s suc-
cess was that most of the participants, throughout the
microwave industry, had been involved in the devel-
opment of various aspects of microwave solid-state
technology for many years, knew each other, and had a
high level of respect for one another.
Every year from 1989 to 1994, a MIMIC conference
was held to discuss technical program and product
availability. System program office personnel were
strongly encouraged to attend these conferences, visit
the exhibits, and discuss their requirements for incor-
porating MMICs into their systems. In addition, the
conferences included demonstrations not only of MMIC
chips and modules but also of the use of MMICs in sys-
tems and subsystems. Rump sessions were conducted
during one or more evenings to discuss problems
encountered during the course of the program and elicit
suggestions for eliminating them. Finally, in addition to
these conferences, MIMIC introductory courses and
workshops were developed by Bert Berson of Berson &
Associates and held throughout the United States on a
periodic basis. (A portion of the information in this sec-
tion was developed and presented by the author to the
Joint DSB/DSAC Task Force on Critical Technologies:
Electronic Components Panel on 5 May 2005.)
ConclusionsIt was a great honor to be entrusted with the responsi-
bility of serving as the director of the MIMIC Program.
Every person and every company that participated in
the program should be proud of contributing to the
many successful outcomes of the program. There was
an incredible amount of cooperation among all the
people and companies involved, and that was a major
reason for its success. Many of the high-volume, high-
yield production facilities established by the contrac-
tor participants are still being used today to produce
high-performance, reliable, affordable MMICs, includ-
ing ones made from InP and GaN. These MMICs have
resulted in the realization of military systems with
markedly improved performance and reliability char-
acteristics and commercial products that are used by
nearly everyone on a daily basis. The program contin-
ues to serve as a model for ongoing and future efforts
to advance microwave, millimeter-wave, submillime-
ter-wave and THz-frequency solid-state electronics.
AcknowledgmentsThe author wishes to thank Vijay Nair of Intel; David
McQuiddy of TriQuint (formerly the TI leader of
the Raytheon/TI MIMIC Joint Venture Team); Fred
Schindler (formerly a member of the Raytheon/
TI MIMIC Joint Venture team and now at RF Micro
Devices); and Reynold Kagiwada, Rich Lai, and Aaron
Oki of NGAS (formerly TRW) for providing the pho-
tographs for this paper. Because the MIMIC Program
ended in 1995, before the era of digital photography, it
was quite difficult to obtain graphic material related to
the program, and their help was invaluable.
The author, regrettably, could not include the names
of all of the individuals who participated in the MIMIC
Program, though unquestionably they all deserve rec-
ognition and respect. All the program participants—
from DoD, from industry, and from academe—assigned
people of outstanding talent to participate in the MIMIC
Program. It was this extraordinary collective talent
pool, working within a well-conceived program struc-
ture and supported by adequate funding, that enabled
the attainment of the myriad of successful MIMIC Pro-
gram results. All of you have the author’s sincere thanks
and appreciation for your significant contributions.
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