In this work we demonstrate high performance and low-power n-type inverters using solution-based CdS as the semiconductor in thin film transistors. Our fabrication process consists of five mask levels and a maximum temperature of 150 °C. The CdS is deposited using chemical bath deposition at 70 °C to provide full compatibility with flexible substrates. Isolated TFTs showed mobilities up to 10 cm2/V-s and threshold voltages of approximately 0.5V. Inverters were biased at 1, 3 and 5 V, resulting in maximum gains in the range of 60 at VDD = 3V. The devices and circuits are fully patterned using standard photolithographic techniques that can be used to design more complex circuitry for flexible and large area electronic applications. In addition we used an extraction parameter method for our TFTs that allows the use of regular SPICE simulation software to design and test the circuits. Our simulations are in good agreement with the experimental data for isolated devices and inverters. Other circuits such as NAND gates are also demonstrated.
In this work we assess the feasibility of ZnO films deposited from a sol gel precursor as a material for thin film charged particle detectors. There are many reports of polycrystalline ZnO thin film transistors (TFTs) in the literature, deposited by sputtering, pulsed laser deposition, and sol gel. There are also reports of sol gel derived ZnO doped with Li or Mg to increase the resistivity, however, these works only measure resistivity of the films, without determining the effect of doping on the carrier concentration. We study the effects of doping the ZnO with Mg and Li as well as the effects of thickness on the films’ resistivity, mobility, and carrier concentration, since these material parameters are critical for a charged particle sensor. Carrier concentration is particularly important because it must be kept low in order for the intrinsic region of a p-i-n diode to be depleted. In order to accomplish this we fabricate and electrically characterize test structures for resistivity, test structures for hall measurement, common back-gate TFTs, and metal-insulator-semiconductor (MIS) capacitors. We also conduct physical characterization techniques such as x-ray diffraction (XRD), atomic force microscopy (AFM), electron microscopy, UV-Vis spectroscopy, and ellipsometry to determine the effect of doping and film thickness on the microstructure and optical properties of the ZnO.
The demand for displays with a large number of pixels is being driven by both military and commercial applications. Displays with very high information content are expected to have >1Gigapixels, requiring I/O bandwidth well beyond current integrated circuit technology, if display architectures continue as they have in the past. In this paper we present a concept based on latched pixels and data processing at the pixel level that could provide a significant reduction in display bandwidth.
KEYWORDS: LCDs, Flat panel displays, Field emission displays, Manufacturing, Military display technology, Display technology, Defense and security, Computing systems, CRTs, Control systems
Flat panel display research has comprised a substantial portion of the national investment in new technology for economic and national security for the past nine years. These investments have ben made principally via several Defense Advanced Research Projects Agency (DARPA) programs, known collectively as the continuing High Definition Systems Program, and the Office of the Secretary of Defense Production Act Title III Program. Using input from the Army, Navy, and Air Force to focus research and identify insertion opportunities, DARPA and the Title III Program Office have made investments to develop the national technology base and manufacturing infrastructure necessary to meet the twin challenge of providing affordable displays in current systems and enabling the DoD strategy of winning future conflicts by getting more information to all participants during the battle. These research programs are reviewed and opportunities for applications are described. Future technology development, transfer, and transition requirements are identified. Strategy and vision are documented to assist the identification of areas meriting further consideration.
Proceedings Volume Editor (2)
This will count as one of your downloads.
You will have access to both the presentation and article (if available).
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.