{"id":1949,"date":"2010-07-13T16:46:33","date_gmt":"2010-07-13T20:46:33","guid":{"rendered":"https:\/\/wpmu2.mit.local\/?p=1949"},"modified":"2010-07-13T17:16:55","modified_gmt":"2010-07-13T21:16:55","slug":"zinc-oxide-nanowire-devices","status":"publish","type":"post","link":"https:\/\/wpmu2.mit.local\/zinc-oxide-nanowire-devices\/","title":{"rendered":"Zinc Oxide Nanowire Devices"},"content":{"rendered":"
\"Figure<\/a>

Figure 1: Design layout of a ZnO-nanowire-based touch sensor with vertically grown nanowires imbedded in a polymer matrix and sandwiched between top and bottom contacts.<\/p><\/div>\n

\"Figure<\/a>

Figure 2: SEM micrograph of horizontally grown ZnO nanowires across ~1\u00b5m trenches.<\/p><\/div>\n

Devices made utilizing zinc oxide (ZnO) nanowires have been developed for a variety of different applications including tactile sensors, flex sensors, transparent field-effect transistors (FETs), and ultra-violet (UV) sensors [1<\/a>]<\/sup> [2<\/a>]<\/sup>. Zinc oxide is an optically transparent, piezoelectric, piezoresistive, and direct wide-band-gap semiconducting material. By taking advantage of a sub-100\u00b0C hydrothermally based growth of ZnO nanowires, the devices can be made directly on flexible and transparent substrates in large areas and at low cost without the need for a transfer process [3<\/a>]<\/sup>. The nanowires can be grown either in the vertical direction, normal to the substrate, or in the horizontal direction, in-plane with the substrate, depending on the device specifications and fabrication process. The tactile sensor devices developed are based on a cross-bar network comprising a top and bottom array of electrodes around a composite of vertically grown nanowires and an insulating polymer (Figure 1). This cross-bar network allows for individually addressable locations for tactile sensing based on the piezoelectric effect. The results for the tactile sensor show a clear spike in current when an insulating tip is placed on and removed from the surface [2<\/a>]<\/sup>. These results are compared to control runs including a touch on the adjacent cross electrodes and testing devices without nanowires. Both tests show at least an order-of-magnitude difference in current between the control and the pressure sensor.<\/p>\n

Growing ZnO nanowires in-plane to the surface at a low temperature can produce many new devices, including a single-nanowire FET and UV sensor (Figure 2). The combination of standard optical lithography and solution-based nanowire growth means that devices can be fabricated on a large scale. Initial results show promise that an in-situ single-nanowire UV sensor and FET can be achieved.<\/p>\n

\r\nReferences
  1. Z. L. Wang, \u201cNovel Nanostructures of ZnO for Nanoscale Photonics, Optoelectronics, Piezoelectricity, and Sensing,\u201d Appl. Phys. A<\/em>, vol. 88, pp 7 \u2013 15, 2007. [↩<\/a>]<\/li>
  2. S. M. Pfaendler, M. E. Swanwick, A. R. Rachamim, P. Beecher, S. E. Machin, P. Andrew, W. I. Milne, and A. J. Flewitt, \u201cA Large-area, Touch-sensitive Surface Comprising of a Zinc Oxide Nanowire Composite for Display Applications,\u201d presented at 2009 MRS Fall Meeting<\/em>, Boston, MA, December 2009. [↩<\/a>] [↩<\/a>]<\/li>
  3. A. R. Rachamim, S. H. Dalal, M. E. Swanwick, A. J. Flewitt, and W. I. Milne, \u201d Quantitative Investigation of the Factors Affecting the Hydrothermal Growth of Zinc Oxide Nanowires,\u201d presented at 2009 MRS Spring Meeting<\/em>, San Francisco, CA, April 2009. [↩<\/a>]<\/li><\/ol><\/div>","protected":false},"excerpt":{"rendered":"

    Devices made utilizing zinc oxide (ZnO) nanowires have been developed for a variety of different applications including tactile sensors, flex…<\/p>\n<\/div>","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[28,11],"tags":[4064],"_links":{"self":[{"href":"https:\/\/wpmu2.mit.local\/wp-json\/wp\/v2\/posts\/1949"}],"collection":[{"href":"https:\/\/wpmu2.mit.local\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/wpmu2.mit.local\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/wpmu2.mit.local\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/wpmu2.mit.local\/wp-json\/wp\/v2\/comments?post=1949"}],"version-history":[{"count":6,"href":"https:\/\/wpmu2.mit.local\/wp-json\/wp\/v2\/posts\/1949\/revisions"}],"predecessor-version":[{"id":1992,"href":"https:\/\/wpmu2.mit.local\/wp-json\/wp\/v2\/posts\/1949\/revisions\/1992"}],"wp:attachment":[{"href":"https:\/\/wpmu2.mit.local\/wp-json\/wp\/v2\/media?parent=1949"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wpmu2.mit.local\/wp-json\/wp\/v2\/categories?post=1949"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wpmu2.mit.local\/wp-json\/wp\/v2\/tags?post=1949"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}