Dr Richard Lang

1
Overview of the Transduction Devices Materials
(TDM) Research Theme

• Dr Richard Lang
• TDM Theme Leader
• Technical Director, Filtronic Components Ltd.

2
Transduction Devices Materials Theme

• One of four specific EMRS DTC themes TDM, RF,
  EO, TEP
• The TDM research theme is by nature closely
  related to the research work of the other themes,
  in particular to the RF Systems theme work.
• This theme provides key technology building
  blocks or technology enablers for RF and
  microwave systems.
• Specifically, the TDM theme is focused on
  research into RF Microwave Materials, Devices,
  Circuits Packaging all being tailored to
  match emerging defence systems requirements.
• Only selected areas, which potentially offer the
  highest leverage to the MOD, are considered
  within this research theme.

3
Broad TDM Technology Research Aims

• Seek reductions in Size, Weight and Power of
  future microwave modules in Radar, UAV and EW
  systems. Emphasis on use of cross-cutting and
  emerging technologies.
• Investigate advanced component and circuit
  concepts for use in complex future systems such
  as adaptive array radars and next generation EW
  systems
• Prove underpinning TDM technologies for future RF
  microwave systems TDM technologies are the
  building blocks of systems.
• Demonstrate to system designers, substantial
  improvements in base technologies of materials,
  devices circuits (ie NOT incremental).
  Technology should be exploitable.
• Focus projects on real requirements and
  continuously review potential for exploitation.
• Ensure UK defence base has access to new and
  emerging TDM technologies reduce effects of
  governmental export restrictions (ITAR)

These aims require continuous and critical
monitoring of RD to ensure that promising
technologies are properly supported and pulled
through.
4
Specific TDM Technology Research Areas

• Semiconductor Materials and Devices
• Efficient, broadband, detection, high-power
  generation and amplification at microwave, mm
  wave terahertz frequencies using III-V and wide
  band-gap semiconductors
• Ensure UK access to critical semiconductor
  devices at affordable cost
• MEMS, nanotechnology, photonics and innovative
  integration on Silicon and/or SiGe
• RF Microwave circuits
• Size reduction
• High dynamic range A/D converters
• Rapidly tuneable low-loss filters
• Receiver protection against high power electronic
  attack
• Efficient microwave PAs sources
• Integrated mixed technology applications
  (microwave/digital, EO/microwave etc.)
• Novel MMICs for microwave and MM-Wave
  applications
• Technology for advanced multifunctional radars
  and active RF resource management
• Modelling (for significant improvements in size
  or performance)
• Packaging Substrate Materials
• Improve system performance through innovative
  packaging techniques
• ultra low-cost packaging techniques
• 3D microwave interconnect
• Improved packaging and thermal management of high
  power devices

5
Active TDM Projects Materials Devices (1)

• GaN for next generation sensors (QinetiQ)
• investigation of the growth of GaN devices on
  silicon substrate (alternative to SiC)
• GaN based HFETs for high power operation
  (Sheffield University)
• Fabrication of HFET devices on QinetiQ GaN-on-Si
• CVD Diamond MESFETs for RF Power applications
  (Element Six)
• Investigating delta-doped diamond MESFETS
• Why fund wide band-gap devices?
• Specifically mentioned in the Defence Technology
  Strategy.
• Have potential to replace established GaAs
  technology with devices that offer higher
  operating voltages, operate at higher
  temperatures, offer substantially higher power
  density, and require less circuit protection
• Reduced die size (per watt) or higher power
  output (per die)
• No UK capability although emerging capability
  in Europe

Pt-gate on GaN written by e-beam
Each of the WBG projects have demonstrated
potential and have been awarded DTC extension
projects for 2007
6
Active TDM Projects Materials Devices (2)

• InP Feasibility Study (Selex SAS)
• Studied UKs future military need for high speed,
  complex, mixed analogue/digital RFICs implemented
  using state-of-the-art SiGe or InP bipolar
  technologies.
• Final report under review
• Diamond MEMS switches (Pre-Cursor Filtronic
  Ulm University)
• Can diamond MEMS be used for ultra-fast microwave
  switching?
• Potential of higher power handling capability,
  with reduced RF leakage
• Final report under review

Reports from both projects are now under review
prior to decisions being made on their
recommendations
Large area MEMS cantilever
7
Active TDM Projects Circuits Packaging

• Broadband Microwave Frequency Selective Limiter
  (Leeds University)
• selective limiting of high level interfering
  signals - preserve dynamic range
• Compact LHM reconfigurable Meta-materials for
  RF/Microwave ICs (UMIST)
• Using left-handed materials techniques to
  investigate compact microwave filter structures,
  with a goal of reducing the size of circuits
• Novel Multi-layer Liquid Crystal Polymer (LCP)
  Packages for High Power Applications
  (Filtronic/BAES-ATC)
• low-cost alternative to ceramic. High-spec
  microwave material - easy to process
  (multi-layer) allows complex multi-layer
  applications.
• LCP laminates have favourable microwave and
  moisture absorption properties.
• X-band T/R module demonstrator

LCP Circuit bonded to Al carrier MMIC and 4W
pHEMT device mounted in cavities
8
New TDM Projects for 2007

• UK source for mm-wave imager MMIC technology
  (QinetiQ/Glasgow Uni)
• Two initial aims
• Define the requirements for specific mm-wave
  imaging systems
• Study a microstrip-based, monolithic GaAs mHEMT,
  mm-wave, imager
• Planar Gunn Diode sources for frequencies at and
  above 100GHz (Aberdeen Uni)
• Planar architecture enables easier MMIC
  integration
• Gunn diodes and triodes demonstrated by Aberdeen
  - frequencies 30GHz to 108 GHz
• Based on a MESFET design that demonstrated the
  Gunn effect in the channel.
• Power measured at about 1µW and needs to be
  increased to be useful.
• Novel Development Methodology for Highly
  Efficient Ultra-Broadband Remote Sensing
  Applications (Cardiff Uni)
• Aims to improve output power and PAE of future
  wideband microwave systems. Already demonstrated
  at 2GHz for cellular applications
• Novel concept uses measurement of I V waveforms
  at interfaces between components.
• Shows real load lines and insight into RF device
  operation.
• Utilises all non-linear information within a
  microwave system to allow optimisation of large
  signal performance.

9
Summary TDM Theme

• Broad TDM theme objectives described
• Specific theme technologies identified within the
  areas of RF Microwave materials, devices
  circuits
• Current projects described - key features
  identified
• New projects for 2007 outlined - watch out for
  progress during 2008.
• Reminder Dont forget to check out the TDM
  posters during the conference

r.lang_at_fcl.com Tel [phone] www.filtronic.c
o.uk