Download A05-040

A05-040
TITLE: Compact, Efficient Sub-Millimeter Wave Electronic Oscillator
TECHNOLOGY AREAS: Materials/Processes, Electronics
OBJECTIVE: Develop and demonstrate a compact electronic oscillator with significant output power and
high efficiency at sub-millimeter wave frequencies.
DESCRIPTION: The drive to increase imaging resolution and communication bandwidth has pushed the
operating frequency of electronic devices higher and higher. Above the millimeter wave range, a
significant barrier exists due to the lack of compact, efficient oscillators with significant output power.
Scientists and engineers are pursuing a number of techniques to remove this barrier, from both the lower
bound using solid-state oscillators and frequency multipliers, and from the upper bound using optical
heterodyning and quantum cascade lasers. Unfortunately, none of these approaches currently can produce
the desired output power levels at the target frequencies in a compact, efficient device. Other researchers
have tried scaling traditional linear-beam vacuum electron devices to operate at shorter wavelengths, but
have encountered difficulty fabricating the devices to the required dimensional tolerances. Other
significant barriers to the use of linear-beam vacuum electronic devices include the availability of reliable
cold cathodes and the large, heavy magnetic circuits typically required to accurately control the electron
beam. The primary goal of this topic is to identify, investigate, and develop an electronic oscillator using a
completely new and innovative approach, rather than an evolutionary improvement of existing techniques.
Responsive approaches could include but are not limited to micromachined vacuum electronics that do not
rely on linear electron beam transport, solid-state techniques that do not rely on frequency multiplication,
and nanoscale mechanical resonators. The target output power level should be in the range of 100 mW to 1
W, with target wall-plug efficiency above 10%. High stability and low phase noise are more desirable than
tunability. The sources themselves should be compact and lightweight, and must have minimal
requirements for ancillary components such as magnets, power supplies, and cooling systems. Device
operating performance including but not limited to output frequency, output power, thermal management,
and wall-plug efficiency will be demonstrated in Phase I by applying standard modeling and simulation
tools. The feasibility of fabricating the device, particularly if micromachining techniques will be used, will
be demonstrated in Phase I using CAE and fabrication flow modeling tools. The resulting data will be used
to produce a device design, process flow, and test plan for a working prototype device to be fabricated and
tested in Phase II.
PHASE I: Demonstrate the feasibility and predicted operating performance of the proposed device through
extensive computer modeling and simulation. Develop and document the design, process flow, and test
plan that will lead to a working prototype device in Phase II.
PHASE II: Construct, test, and evaluate the performance of the prototype device designed in Phase I.
Document the final design and measured performance of the prototype device.
PHASE III DUAL USE APPLICATIONS: Using the results of the prototype demonstration in Phase II,
develop and document a device design, fabrication process, cost model, and preliminary path to large-scale
commercial manufacturability of the device. The device design and fabrication process should be oriented
towards maximizing the economies of scale, using batch processing and monolithic integration of device
components to simplify assembly wherever possible. This compact, efficient, low cost, sub-millimeter
wave power source will open up new areas of basic research along with new military and commercial
applications including space-based communications, wide bandwidth communications and sensing for
satellite systems, short-range terrestrial and airborne communications, chemical and biological sensing,
near object spectroscopic analysis, high-resolution medical imaging, and high-resolution radar.
REFERENCES:
1) Peter H. Siegel, "Terahertz Technology," IEEE Trans. Microwave Theory Tech., vol. 50, no. 3, pp. 910–
928, March 2002.
2) H. M. Manohara, P. H. Siegel, C. Marrese, B. Chang, and J. Xu, "Fabrication and emitter measurements
for a nanoklystron: A novel THz micro-tube source," Proc. Third IEEE International Vacuum Electronics
Conference, pp. 28–29, 2002.
3) P. D. Coleman, "Reminiscences on selected millennium highlights in the quest for tunable terahertzsubmillimeter wave oscillators," IEEE Journal of Selected Topics in Quantum Electronics, vol. 6, no. 6, pp.
1000–1007, November/December 2000.
4) Whitaker, Jerry C. Power Vacuum Tubes Handbook, Second Edition. Boca Raton, Florida: CRC Press,
1999.
KEYWORDS: sub-millimeter wave, vacuum electronics, micromachining, nanotechnology