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<article article-type="research-article">
  <front>
    <journal-meta>
      <journal-id journal-id-type="aggregator">72010410</journal-id>
      <journal-title>NIP &amp; Digital Fabrication Conference</journal-title>
      <abbrev-journal-title>nip digi fabric conf</abbrev-journal-title>
      <issn pub-type="ppub">2169-4451</issn><issn pub-type="epub"/>
      <publisher>
        <publisher-name>Society of Imaging Science and Technology</publisher-name>
        <publisher-loc>7003 Kilworth Lane, Springfield, VA 22151, USA</publisher-loc>
      </publisher>
    </journal-meta>
    <article-meta><article-id pub-id-type="doi">10.2352/ISSN.2169-4451.2005.21.2.art00043_3</article-id>
      <article-id pub-id-type="sici">2169-4451(20050101)2005:3L.131;1-</article-id>
      <article-id pub-id-type="publisher-id">nip_v2005n3/splitsection43.xml</article-id>
      <article-id pub-id-type="other">/ist/nipdf/2005/00002005/00000003/art00043</article-id>
      <article-categories>
        <subj-group>
          <subject>Articles</subject>
        </subj-group>
      </article-categories>
      <title-group>
        <article-title>Large Area Distributed Electronics</article-title>
      </title-group>
      <contrib-group>
        <contrib>
          <name>
            <surname>Reuss</surname>
            <given-names>Robert</given-names>
          </name>
        </contrib>
      </contrib-group>
      <pub-date>
        <day>01</day>
        <month>01</month>
        <year>2005</year>
      </pub-date>
      <volume>2005</volume>
      <issue>3</issue>
      <fpage>131</fpage>
      <lpage>131</lpage>
      <permissions>
        <copyright-year>2005</copyright-year>
      </permissions>
      <abstract>
        <p>Microelectronics and, particularly, silicon integrated circuit microelectronics, has produced amazing capabilities over the last 40 years. There are numerous indicators of this, but best summarized as &#x201C;Moore's Law.&#x201D; While more transistors/ cm<sup>2</sup> is the driving
 force, the microelectronics-based display industry has, for over a decade also explored alternate directions &#x2013; larger and larger &#x201C;chips&#x201D; and/or alternative substrates. Thus, displays have grown from several in<sup>2</sup> to several ft<sup>2</sup> while the number of transisors/cm<sup>2</sup>
 has remained small. Further, major R &amp; D investment has been made in migrating from a glass substrate &#x201C;chip&#x201D; to a plastic one in order to achieve increased functionality (again without increasing the transistors/ cm<sup>2</sup>).The relatively low cost manufacturing process
 used for displays has created significant interest in applying this form of microelectronics to other classes of problems. An example is an image array. Here the amorphous TFT can also be used as a light sensor. This leads to digital x-rays with many advantages over the conventional film based
 methods. The sensor function might also cover other parts of the EM spectrum to provide a large area IR imager or RF antenna array (communications and radar). Other sensor techniques would provide the capability to monitor stress or corrosion while integration of actuators would lead to the
 capability to not just monitor the environment, but to respond to it (modification of a property in response to a stimulus).To accomplish such sensor applications, more transistors/ cm<sup>2</sup> is not the issue. Rather the ability to cost effectively fabricate modest numbers of integrated
 devices (&lt;10<sup>5</sup>) over large areas (&gt;ft<sup>2</sup>) is essential. Even then, other attributes may also be required (such as flexible substrate). Perhaps the most demanding feature that has not been developed by either the integrated circuit or display industries is a high performance
 TFT.Transistor performance is determined by materials properties and critical dimensions. Microelectronics progress has been based on the favorable material characteristics of silicon (and its oxide) and the drastic scaling (from 10's of microns to tenths of microns) that has been
 achieved. Cost effective manufacture of TFTs over large areas limits both the material and dimensional properties that can be achieved and results in a 10-100x reduction in device performance. While not a significant limitation for displays, it is for applications that require performance
 in the MHz and higher regime.One approach to achieving higher performance TFTs is to improve the process conditions that are currently used to fabricate poly TFTs. This might be achieved by better recrystallization and oxidation methods or by processing &#x201C;off line&#x201D; and then
 transferring onto the preferred substrate. While such methods are well known, there are still challenging technical hurdles. A novel means to circumvent many of these problems might be accomplished via printing of Si nanowires or C nanotubes as the active material of TFTs. Both materials have
 significant issues, which must be overcome.DARPA is currently funding work in a variety of areas expected to impact the migration of microelectronics from &#x201C;smaller is better&#x201D; to &#x201C;bigger is better&#x201D;. Status and objectives of these efforts will be presented especially
 from the perspective of opportunities to achieve the desired results with digital fabrication methods.</p>
      </abstract>
    </article-meta>
  </front>
</article>
