{"id":909,"date":"2013-06-27T19:48:04","date_gmt":"2013-06-27T19:48:04","guid":{"rendered":"https:\/\/mtlsites.mit.edu\/annual_reports\/2013\/?p=909"},"modified":"2013-07-25T18:31:27","modified_gmt":"2013-07-25T18:31:27","slug":"towards-highly-scaled-gate-length-asymmetrically-strained-ge-nanowire-p-mosfets","status":"publish","type":"post","link":"https:\/\/mtlsites.mit.edu\/annual_reports\/2013\/towards-highly-scaled-gate-length-asymmetrically-strained-ge-nanowire-p-mosfets\/","title":{"rendered":"Towards Highly Scaled Gate Length Asymmetrically Strained Ge Nanowire p-MOSFETs"},"content":{"rendered":"<p>Ge nanowires are of interest for future sub-10-nm gate length p-MOSFETs because of the excellent electrostatic control afforded by the non-planar device geometry and the potential for high hole velocity in strained Ge.\u00a0 In this work, <i>asymmetrically<\/i> strained Ge was explored and compared to biaxially strained Ge. Asymmetric strain is a strain state that is neither uniaxial nor biaxial but somewhere in between.\u00a0 Asymmetric strain was generated by lateral relaxation of biaxial strain as a result of nanowire formation, due to the free surfaces that are created as shown in Figure 1. To explore asymmetric strain, biaxially strained strained Ge-on-insulator (SGOI) wafers were first fabricated using a bond and etch-back process [1].\u00a0The wafers were then used to fabricate long-channel asymmetrically strained nanowire trigate Ge p-MOSFETs and on-chip biaxially strained planar Ge p-MOSFETs (Figure 2). The enhancement in mobility for high charge density for wide asymmetrically strained nanowires is 2.0x relative to biaxially strained Ge and 15x relative to Si hole universal mobility<sup>[<a href=\"#footnote_0_909\" id=\"identifier_0_909\" class=\"footnote-link footnote-identifier-link\" title=\"W. Chern, P. Hashemi, J. T. Teherani, T. Yu, Y. Dong, G. Xia, D. A. Antoniadis, and J. L. Hoyt, &ldquo;High Mobility High-&kappa;-All-Around Asymmetrically-Strained Germanium Nanowire Trigate p-MOSFETs,&rdquo; in IEDM Tech. Dig., 2012, pp. 387-390.\">1<\/a>]<\/sup>. The enhancement in mobility promises significant improvement of the hole transport relative to both biaxially strained Ge and state-of-the-art Si, for asymmetrically strained Ge at scaled gate lengths.\u00a0 Progress is being made in developing a process for highly scaled gate length transistors where the viability of asymmetrically strained Ge as a material for improving the performance of MOSFETs is under analysis.<\/p>\n<ol class=\"footnotes\"><li id=\"footnote_0_909\" class=\"footnote\">W. Chern, P. Hashemi, J. T. Teherani, T. Yu, Y. Dong, G. Xia, D. A. Antoniadis, and J. L. Hoyt, \u201cHigh Mobility High-\u03ba-All-Around Asymmetrically-Strained Germanium Nanowire Trigate p-MOSFETs,\u201d in <i>IEDM Tech. Dig.<\/i>, 2012, pp. 387-390. [<a href=\"#identifier_0_909\" class=\"footnote-link footnote-back-link\">&#8617;<\/a>]<\/li><\/ol>","protected":false},"excerpt":{"rendered":"<p>Ge nanowires are of interest for future sub-10-nm gate length p-MOSFETs because of the excellent electrostatic control afforded by the&#8230;<\/p>\n","protected":false},"author":370,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[28,8,6083],"tags":[11449,6204],"_links":{"self":[{"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2013\/wp-json\/wp\/v2\/posts\/909"}],"collection":[{"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2013\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2013\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2013\/wp-json\/wp\/v2\/users\/370"}],"replies":[{"embeddable":true,"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2013\/wp-json\/wp\/v2\/comments?post=909"}],"version-history":[{"count":12,"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2013\/wp-json\/wp\/v2\/posts\/909\/revisions"}],"predecessor-version":[{"id":2302,"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2013\/wp-json\/wp\/v2\/posts\/909\/revisions\/2302"}],"wp:attachment":[{"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2013\/wp-json\/wp\/v2\/media?parent=909"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2013\/wp-json\/wp\/v2\/categories?post=909"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2013\/wp-json\/wp\/v2\/tags?post=909"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}