{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,14]],"date-time":"2025-10-14T06:54:51Z","timestamp":1760424891359,"version":"3.41.2"},"reference-count":6,"publisher":"AIP Publishing","issue":"7","content-domain":{"domain":["pubs.aip.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2008,4,1]]},"abstract":"<jats:p>This work reports for the first time results on MgO tunnel junctions prepared by ion beam. The MgO barrier was deposited from a ceramic MgO target using an assisted beam, following the deposition and assisted beam phase diagram which relate the beam profile with the current and energy. The deposition rate for MgO is calculated with and without assisted beam, and compared with the experimental values. The MgO film growth on Ta\u2215CoFeB\u2215MgO simple stacks was optimized aiming at a (002) preferred orientation for the MgO growth, measured by x-ray diffraction. The optimum assist beam energy was tuned for each deposition beam condition (+800,+1000,+1200V), using assist beams of 40mA\u2008(\u223c130\u03bcA\u2215cm2) with 0to+600V. Without assist beam, no texture is observed for the MgO, while the (002) orientation appears for assisted deposition. The optimum range of assist voltages is large, being limited by the onset of etching at high voltages, reducing the deposition rate. Magnetic tunnel junctions were deposited with the structure Ta 50\u00c5\u2215Ru\u2008200\u00c5\u2215Ta\u200850\u00c5\u2215Mn78Ir22\u2008150\u00c5\u2215Co90Fe10\u200830\u00c5\u2215Ru\u20088\u00c5\u2215Co56Fe24B20\u200840\u00c5\u2215MgO\u2008t\u2215Co56Fe24B20\u200830\u00c5\u2215Ru\u200830\u00c5\u2215Ta\u200850\u00c5, with the MgO barrier deposited with the conditions optimized by x rays. The effect of the assist beam energy on the junction properties (magnetoresistance and magnetization) are discussed. Tunnel magnetoresistance values up to 110%, with RA products of 100\u2013400\u03a9\u03bcm2, for 11\u00c5 thick MgO barriers are obtained using assisted deposition with a +100V assist beam, which is a major improvement of the \u223c30% of TMR, if no beam is used.<\/jats:p>","DOI":"10.1063\/1.2833823","type":"journal-article","created":{"date-parts":[[2008,2,7]],"date-time":"2008-02-07T23:32:40Z","timestamp":1202427160000},"update-policy":"https:\/\/doi.org\/10.1063\/aip-crossmark-policy-page","source":"Crossref","is-referenced-by-count":23,"title":["Ion beam assisted deposition of MgO barriers for magnetic tunnel junctions"],"prefix":"10.1063","volume":"103","author":[{"given":"S.","family":"Cardoso","sequence":"first","affiliation":[{"name":"Instituto de Engenharia de Sistemas e Computadores\u2014Microsistemas e Nanotecnologias , (INESC-MN), R.Alves Redol, 9-1\u00b0, 1000-029 Lisbon, Portugal and , Av Rovisco Pais, 1000 Lisboa, Portugal"},{"name":"Instituto Superior T\u00e9cnico\u2014Depart. de F\u00edsica , (INESC-MN), R.Alves Redol, 9-1\u00b0, 1000-029 Lisbon, Portugal and , Av Rovisco Pais, 1000 Lisboa, Portugal"}]},{"given":"R. J.","family":"Macedo","sequence":"additional","affiliation":[{"name":"Instituto de Engenharia de Sistemas e Computadores\u2014Microsistemas e Nanotecnologias , (INESC-MN), R.Alves Redol, 9-1\u00b0, 1000-029 Lisbon, Portugal and , Av Rovisco Pais, 1000 Lisboa, Portugal"},{"name":"Instituto Superior T\u00e9cnico\u2014Depart. de F\u00edsica , (INESC-MN), R.Alves Redol, 9-1\u00b0, 1000-029 Lisbon, Portugal and , Av Rovisco Pais, 1000 Lisboa, Portugal"}]},{"given":"R.","family":"Ferreira","sequence":"additional","affiliation":[{"name":"Instituto de Engenharia de Sistemas e Computadores\u2014Microsistemas e Nanotecnologias , (INESC-MN), R.Alves Redol, 9-1\u00b0, 1000-029 Lisbon, Portugal and , Av Rovisco Pais, 1000 Lisboa, Portugal"},{"name":"Instituto Superior T\u00e9cnico\u2014Depart. de F\u00edsica , (INESC-MN), R.Alves Redol, 9-1\u00b0, 1000-029 Lisbon, Portugal and , Av Rovisco Pais, 1000 Lisboa, Portugal"}]},{"given":"A.","family":"Augusto","sequence":"additional","affiliation":[{"name":"Instituto de Engenharia de Sistemas e Computadores\u2014Microsistemas e Nanotecnologias , (INESC-MN), R.Alves Redol, 9-1\u00b0, 1000-029 Lisbon, Portugal and , Av Rovisco Pais, 1000 Lisboa, Portugal"},{"name":"Instituto Superior T\u00e9cnico\u2014Depart. de F\u00edsica , (INESC-MN), R.Alves Redol, 9-1\u00b0, 1000-029 Lisbon, Portugal and , Av Rovisco Pais, 1000 Lisboa, Portugal"}]},{"given":"P.","family":"Wisniowski","sequence":"additional","affiliation":[{"name":"Instituto de Engenharia de Sistemas e Computadores\u2014Microsistemas e Nanotecnologias , (INESC-MN), R.Alves Redol, 9-1\u00b0, 1000-029 Lisbon, Portugal and , Av Rovisco Pais, 1000 Lisboa, Portugal"},{"name":"Instituto Superior T\u00e9cnico\u2014Depart. de F\u00edsica , (INESC-MN), R.Alves Redol, 9-1\u00b0, 1000-029 Lisbon, Portugal and , Av Rovisco Pais, 1000 Lisboa, Portugal"}]},{"given":"P. P.","family":"Freitas","sequence":"additional","affiliation":[{"name":"Instituto de Engenharia de Sistemas e Computadores\u2014Microsistemas e Nanotecnologias , (INESC-MN), R.Alves Redol, 9-1\u00b0, 1000-029 Lisbon, Portugal and , Av Rovisco Pais, 1000 Lisboa, Portugal"},{"name":"Instituto Superior T\u00e9cnico\u2014Depart. de F\u00edsica , (INESC-MN), R.Alves Redol, 9-1\u00b0, 1000-029 Lisbon, Portugal and , Av Rovisco Pais, 1000 Lisboa, Portugal"}]}],"member":"317","published-online":{"date-parts":[[2008,2,7]]},"reference":[{"key":"2023070319513620100_c1","doi-asserted-by":"publisher","first-page":"08A907","DOI":"10.1063\/1.2176588","volume":"99","year":"2006","journal-title":"J. Appl. Phys."},{"key":"2023070319513620100_c2","doi-asserted-by":"publisher","first-page":"2952","DOI":"10.1109\/20.801044","volume":"35","year":"1999","journal-title":"IEEE Trans. Magn."},{"key":"2023070319513620100_c3","doi-asserted-by":"publisher","first-page":"2955","DOI":"10.1063\/1.120227","volume":"71","year":"1997","journal-title":"Appl. Phys. Lett."},{"key":"2023070319513620100_c4","doi-asserted-by":"publisher","first-page":"042506","DOI":"10.1063\/1.2234720","volume":"89","year":"2006","journal-title":"Appl. Phys. Lett."},{"unstructured":"M.\u2008Davis, G.\u2008Proudfoot, and D.\u2008Pearson, European Patent No. EP1212777 (March 29, 2001).","key":"2023070319513620100_c5"},{"key":"2023070319513620100_c6","doi-asserted-by":"publisher","first-page":"4361","DOI":"10.1109\/20.799086","volume":"35","year":"1999","journal-title":"IEEE Trans. Magn."}],"container-title":["Journal of Applied Physics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/pubs.aip.org\/aip\/jap\/article-pdf\/doi\/10.1063\/1.2833823\/15008059\/07a905_1_online.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/pubs.aip.org\/aip\/jap\/article-pdf\/doi\/10.1063\/1.2833823\/15008059\/07a905_1_online.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,7,3]],"date-time":"2023-07-03T23:23:57Z","timestamp":1688426637000},"score":1,"resource":{"primary":{"URL":"https:\/\/pubs.aip.org\/jap\/article\/103\/7\/07A905\/342474\/Ion-beam-assisted-deposition-of-MgO-barriers-for"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2008,2,7]]},"references-count":6,"journal-issue":{"issue":"7","published-print":{"date-parts":[[2008,4,1]]}},"URL":"https:\/\/doi.org\/10.1063\/1.2833823","relation":{},"ISSN":["0021-8979","1089-7550"],"issn-type":[{"type":"print","value":"0021-8979"},{"type":"electronic","value":"1089-7550"}],"subject":[],"published-other":{"date-parts":[[2008,4,1]]},"published":{"date-parts":[[2008,2,7]]},"article-number":"07A905"}}