MICRA Project Descriptions: Summer 2000
1.
Ferroelectric Materials for Tunable Microwave Applications
C.L. Canedy and R.
Ramesh, Materials Engineering Department, University of Maryland,
S. Tidrow, ARL
Ferroelectric materials offer an enticing prospect for incorporation into frequency-agile microwave electronic components, including phase shifters, tunable filters, varactors and antennas. Ultimately, these materials are envisioned to enter into microwave integrated circuits for possible insertion in satellite and wireless communication platforms. Low microwave losses, low power consumption, small size and weight, low cost and ease of integration into microwave systems are just a few of the stringent requirements which these components must satisfy to be a competing technology. This project is concerned with the growth and characterization of ferroelectric thin films, as well as their processing into test structures for electrical characterization. Ferroelectric thin films will be deposited onto substrates using pulsed laser deposition at the University of Maryland and their quality assessed using materials analysis facilities. The films will be processed to fabricate tet structures for dielectric characterization, which will be carried out at ARL facilities.
2.
Smart Pixel Based Multi-processor Interconnection Concepts for Army Hyperspectral
Sensor Signal Processing Applications
Mike Haney, George Mason University
Under the MICRA effort, faculty and graduate students from George Mason University are collaborating with researchers at the University of Maryland (e.g., Bhattacharyya and Newcomb) and Army Research Laboratory (e.g., Mait, Simonis, Euliss, Lawler) on the development of smart pixel based architectures for application to hyper-spectral sensor processing problems. This is a rich multi-disciplinary area involving many analytical and experimental elements. To achieve success in a summer period, a well-defined experiment must be defined. I propose a summer project for two undergraduate students that combines a narrowly focused experimental effort with a high level analysis of the advantages of smart pixels in the proposed sensor processing architecture.
This project will therefore accomplish the main goal of a well-defined and well-constrained experimental effort, but will also allow the students to put the experiment in proper context by understanding the "big picture." To achieve the second goal, I will encourage the students to provide a "top-level" analysis of the how the smart pixel technology they are evaluating will provide a pay-off in an eventual system. The experimental portion of the program will involve characterizing a to-be-determined smart pixel optical interconnection system that will likely involve a hybrid micro/macro-optical design and ARL-designed CSEL-based smart pixel arrays. The electronic portions of the smart pixels used in the effort will likely be developed at ARL and UMd. The students will be tasked with helping to set up the evaluation system and characterizing it in terms of light efficiency and signal throughput. This effort will involve coordination with personnel from GMU, ARL, and UMd, and will likely take place in ARL's facility. The analytical portions of the project will require the students to interact with a variety of the researchers on the MICRA team through individual contacts and attendance at the MICRA group meetings that occur during the summer period.
3.
VCSEL Based Smart Pixels for Optical Interconnects and Image Processing
Prof. M. Dagenais,
University of Maryland
The objective of this project is to develop and demonstrate 2 dimensional arrays of VCSELs and vertically amplifying structures operating at speeds of multi hundreds of MHz, at power levels on the order of 1mW, with good wall-plug efficiency. The applications of these arrays will be targeted to free-space optical interconnects for signal processing. Smart pixel arrays will ultimately find Army applications in the following areas 1) digital half-tone image processing, 2) VLSI neuromorphic image acquisition and pre-processing, and 3) image processing using pulse-coupled neural networks. It is expected that the summer student will work closely with graduate students, faculty and Army researchers and will get involved with selectively oxidizing VCSELs to reduce the threshold current so that they can be operated using CMOS driver arrays. The VCSELs integrated with CMOS driver chips by flip-chip bonding will then need to be tested for performance and uniformity. The smart-pixels thus obtained, will be used in actual system demonstration. It is an unique opportunity for a student to get involved with cutting edge optoelectronic technology.
Professor Dagenais will direct this project. Professor Dagenais has extensive experience with Optics and Optoelectronics. He presently directs the Photonic Switching and Integrated Optoelectronics Laboratory at the University of Maryland. He is also the Director of the NSF sponsored Center for Optoelectronic Devices, Interconnects, and Packaging. This work will be done in close collaboration with the Army and, in particular, with Dr. G. Simonis who will help with the supervision of the student.
4.
Wide Band Gap Semiconductor Research for High Temperature Electronics
and Optical Devices
Dr. R.D. Vispute
and Prof. T. Venkatesan,
University of Maryland
Wide Band Gap Semiconductor materials such as SiC and Ga-Al-N are useful for the development of high temperature-high power electronics, UV optoelectronic detectors and emitters. These devices have potential applications for the Army in a number of areas. These materials have desirable electronics and optical properties, thermal and chemical stability, tunable wide band gaps, and doping capabilities. In this program, we have the following research activities with an emphasis on growth, characterization, processing and fabrication of high temperature electronics and UV-blue light emitting devices (LEDs). SiC based high temperature devices: Due to its large band gap, high thermal conductivity, high breakdown voltages and saturation velocities, the SiC is suitable for high temperature and high power electronics. The project involves growth and characterization of AlN thin films for passivation and dielectric applications. Ga-Al-N Heterostructures: The III-V nitrides have attracted much attention recently for implementation of high power and high temperature optoelectronic devices, Optoelectronics FETs, solar blind UV detectors, and UV-Blue lasers. The LEDs and lasers are useful for large outdoor displays and televisions. The advent of this technology will also bring changes in the data storage related industries like compact disks and digital videodisks. Metal-oxide based systems for optoelectronics: We have exciting opportunities to develop new optical devices based on Zn-Mg-O material based system. In this project, we will work on thin film growth and multilayers by pulsed laser deposition, doping and alloying. We will characterize the deposited films by various techniques such as Rutherford Backscattering Spectroscopy, Transmission Electron Microscopy, Photoluminescence spectroscopy, and electrical transport measurements (Hall effect, I-V characteristics). Devices will be fabricated using standard photolithographic technique and focussed ion beam system. The projects under this program are designed to educate undergraduates and advance their knowledge and capabilities in the area of semiconductors. Involved in this project, students will acquire: 1) fundamentals of technologically important semiconductors, and 2) hands-on experience on semiconductor processing techniques at the early stages of their education.