{"id":72707,"date":"2025-02-18T14:39:13","date_gmt":"2025-02-18T12:39:13","guid":{"rendered":"https:\/\/www.iemn.fr\/?p=72707"},"modified":"2025-02-25T12:33:10","modified_gmt":"2025-02-25T10:33:10","slug":"memories-that-use-heat-to-store-information","status":"publish","type":"post","link":"https:\/\/www.iemn.fr\/en\/newsletter\/memories-that-use-heat-to-store-information.html","title":{"rendered":"Memories that use heat to store information"},"content":{"rendered":"<section  class='av_textblock_section av-m7afef81-45393b73ab7d0fd6ccfd0537d8206440'   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/BlogPosting\" itemprop=\"blogPost\" ><div class='avia_textblock'  itemprop=\"text\" ><h1 style=\"font-weight: 400; text-align: center;\"><strong><span style=\"color: #991f0f;\">Memories that use heat to store information<\/span><\/strong><\/h1>\n<\/div><\/section>\n<div  class='flex_column av-qdudgj-82d040f4d15c289721dadf4e5bbcf75a av_one_full  avia-builder-el-1  el_after_av_textblock  el_before_av_hr  first flex_column_div  column-top-margin'     ><section  class='av_textblock_section av-m7bylhlx-e98c4e07c485e5283fc3a061e0bce6ed'   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/BlogPosting\" itemprop=\"blogPost\" ><div class='avia_textblock'  itemprop=\"text\" ><div id=\"attachment_72776\" style=\"width: 1410px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/www.iemn.fr\/wp-content\/uploads\/2025\/02\/composants_chaleur_8.jpg\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-72776\" class=\"wp-image-72776 size-full\" src=\"https:\/\/www.iemn.fr\/wp-content\/uploads\/2025\/02\/composants_chaleur_8.jpg\" alt=\"G(T) TiN x3.6 interface \u2013 High-resolution transmission electron microscopy images showing atomic resolution and the chemical composition of the layer.\" width=\"1400\" height=\"344\" srcset=\"https:\/\/www.iemn.fr\/wp-content\/uploads\/2025\/02\/composants_chaleur_8.jpg 1400w, https:\/\/www.iemn.fr\/wp-content\/uploads\/2025\/02\/composants_chaleur_8-300x74.jpg 300w, https:\/\/www.iemn.fr\/wp-content\/uploads\/2025\/02\/composants_chaleur_8-1030x253.jpg 1030w, https:\/\/www.iemn.fr\/wp-content\/uploads\/2025\/02\/composants_chaleur_8-768x189.jpg 768w, https:\/\/www.iemn.fr\/wp-content\/uploads\/2025\/02\/composants_chaleur_8-18x4.jpg 18w, https:\/\/www.iemn.fr\/wp-content\/uploads\/2025\/02\/composants_chaleur_8-705x173.jpg 705w\" sizes=\"auto, (max-width: 1400px) 100vw, 1400px\" \/><\/a><p id=\"caption-attachment-72776\" class=\"wp-caption-text\">G(T) TiN x3.6 interface \u2013 High-resolution transmission electron microscopy images showing atomic resolution and the chemical composition of the layer.<\/p><\/div>\n<\/div><\/section><\/div>\n\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-m7agu8x4-aa7ab05dd1a73089d8d7d712dadb431d\">\n#top .hr.av-m7agu8x4-aa7ab05dd1a73089d8d7d712dadb431d{\nmargin-top:20px;\nmargin-bottom:30px;\n}\n.hr.av-m7agu8x4-aa7ab05dd1a73089d8d7d712dadb431d .hr-inner{\nwidth:50px;\nborder-color:#ad2d24;\nmax-width:45%;\n}\n.hr.av-m7agu8x4-aa7ab05dd1a73089d8d7d712dadb431d .av-seperator-icon{\ncolor:#ad2d24;\n}\n<\/style>\n<div  class='hr av-m7agu8x4-aa7ab05dd1a73089d8d7d712dadb431d hr-custom  avia-builder-el-3  el_after_av_one_full  el_before_av_one_fifth  hr-center hr-icon-yes'><span class='hr-inner inner-border-av-border-fat'><span class=\"hr-inner-style\"><\/span><\/span><span class='av-seperator-icon' aria-hidden='true' data-av_icon='\ue808' data-av_iconfont='entypo-fontello'><\/span><span class='hr-inner inner-border-av-border-fat'><span class=\"hr-inner-style\"><\/span><\/span><\/div>\n<div  class='flex_column av-2zrohca-280c220b1fd57f193d57ff174d6b1206 av_one_fifth  avia-builder-el-4  el_after_av_hr  el_before_av_two_fifth  first flex_column_div av-hide-on-mobile'     ><section  class='av_textblock_section av-2q37gyy-7c9c0cb81a34dd6b26357daa24fc96d1'   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/BlogPosting\" itemprop=\"blogPost\" ><div class='avia_textblock'  itemprop=\"text\" ><p style=\"text-align: center;\"><a href=\"https:\/\/www.iemn.fr\/wp-content\/uploads\/2025\/02\/composants_chaleur_14.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-72826 size-full aligncenter\" src=\"https:\/\/www.iemn.fr\/wp-content\/uploads\/2025\/02\/composants_chaleur_14.jpg\" alt=\"\" width=\"422\" height=\"1715\" srcset=\"https:\/\/www.iemn.fr\/wp-content\/uploads\/2025\/02\/composants_chaleur_14.jpg 422w, https:\/\/www.iemn.fr\/wp-content\/uploads\/2025\/02\/composants_chaleur_14-74x300.jpg 74w, https:\/\/www.iemn.fr\/wp-content\/uploads\/2025\/02\/composants_chaleur_14-378x1536.jpg 378w, https:\/\/www.iemn.fr\/wp-content\/uploads\/2025\/02\/composants_chaleur_14-3x12.jpg 3w, https:\/\/www.iemn.fr\/wp-content\/uploads\/2025\/02\/composants_chaleur_14-369x1500.jpg 369w\" sizes=\"auto, (max-width: 422px) 100vw, 422px\" \/><\/a><\/p>\n<\/div><\/section><\/div>\n<div  class='flex_column av-24syley-97a2ae9d7af8091aafcec3d99e7b0870 av_two_fifth  avia-builder-el-6  el_after_av_one_fifth  el_before_av_two_fifth  flex_column_div'     ><style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-1iv4yay-c0e1112f81de2a5fde6161d2ae4eb73a\">\n#top .av_textblock_section.av-1iv4yay-c0e1112f81de2a5fde6161d2ae4eb73a .avia_textblock{\ntext-align:justify;\n}\n<\/style>\n<section  class='av_textblock_section av-1iv4yay-c0e1112f81de2a5fde6161d2ae4eb73a'   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/BlogPosting\" itemprop=\"blogPost\" ><div class='avia_textblock'  itemprop=\"text\" ><blockquote>\n<p><strong><span style=\"color: #991f0f;\">Electronic components heat up, and this is a source of problems and energy losses. But did you know that some components use heat as a lever to store information? A team from the IEMN is investigating the thermal properties of the so-called \u2018phase change\u2019 materials used in these new types of memory. The results are published in the Journal of Applied Physics.<\/span><\/strong><\/p>\n<\/blockquote>\n<p><strong><span style=\"color: #ff7b00;\"><span style=\"color: #008080;\">\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-mqde7m-725448141568c72c97de4f331a1259f8\">\n.av_font_icon.av-mqde7m-725448141568c72c97de4f331a1259f8{\ncolor:#991f0f;\nborder-color:#991f0f;\n}\n.av_font_icon.av-mqde7m-725448141568c72c97de4f331a1259f8 .av-icon-char{\nfont-size:25px;\nline-height:25px;\n}\n<\/style>\n<span  class='av_font_icon av-mqde7m-725448141568c72c97de4f331a1259f8 avia_animate_when_visible av-icon-style- avia-icon-pos-left avia-icon-animate'><span class='av-icon-char' aria-hidden='true' data-av_icon='\ue857' data-av_iconfont='entypo-fontello' ><\/span><\/span><\/span><\/span>Phase-change memories have a number of advantages, including high miniaturization capacity, low power consumption and the ability to retain their last state after use, hence the term \u2018non-volatile\u2019.\u00a0<\/strong> This very useful property comes from the material used, in our case GeSbTe, a chalcogenide glass with a disordered, electrically insulating phase and conductive crystalline phases. PCM (Phase-Change Memories) use a thin layer of this material and electrodes that heat a nanometric zone of material to make the (reversible) transition between the amorphous and crystalline phases. The information is then stored and read by measuring the electrical resistance of this zone, the \u2018memory point\u2019.<\/p>\n<p><strong><span style=\"color: #ff7b00;\"><span style=\"color: #008080;\">\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-mqde7m-2-e5f5491c2fbb93073bef6f4707a95368\">\n.av_font_icon.av-mqde7m-2-e5f5491c2fbb93073bef6f4707a95368{\ncolor:#991f0f;\nborder-color:#991f0f;\n}\n.av_font_icon.av-mqde7m-2-e5f5491c2fbb93073bef6f4707a95368 .av-icon-char{\nfont-size:25px;\nline-height:25px;\n}\n<\/style>\n<span  class='av_font_icon av-mqde7m-2-e5f5491c2fbb93073bef6f4707a95368 avia_animate_when_visible av-icon-style- avia-icon-pos-left avia-icon-animate'><span class='av-icon-char' aria-hidden='true' data-av_icon='\ue857' data-av_iconfont='entypo-fontello' ><\/span><\/span><\/span><\/span><\/strong>This technology, already used in automotive electronics for example, involves considerable challenges in terms of materials engineering, as the memory point locally reaches temperatures more than 600\u00b0C during melting. Successfully confining such a release of heat to an area of just a few nanometers over a period of less than a microsecond requires knowledge of the material&rsquo;s properties, particularly its thermal properties, as a function of temperature. Furthermore, the composition of the material is highly complex and its properties are not always known precisely.<\/p>\n<\/div><\/section><\/div>\n<div  class='flex_column av-10k23my-479b76c6fc5583d52caf1f8edef4b538 av_two_fifth  avia-builder-el-10  el_after_av_two_fifth  avia-builder-el-last  flex_column_div'     ><style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-w4ush6-636bcff097d0170adb89518aa0499588\">\n#top .av_textblock_section.av-w4ush6-636bcff097d0170adb89518aa0499588 .avia_textblock{\ntext-align:justify;\n}\n<\/style>\n<section  class='av_textblock_section av-w4ush6-636bcff097d0170adb89518aa0499588'   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/BlogPosting\" itemprop=\"blogPost\" ><div class='avia_textblock'  itemprop=\"text\" ><p><strong><span style=\"color: #ff7b00;\"><span style=\"color: #008080;\">\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-mqde7m-1-8d1f54c507518a6285e604bf266568af\">\n.av_font_icon.av-mqde7m-1-8d1f54c507518a6285e604bf266568af{\ncolor:#991f0f;\nborder-color:#991f0f;\n}\n.av_font_icon.av-mqde7m-1-8d1f54c507518a6285e604bf266568af .av-icon-char{\nfont-size:25px;\nline-height:25px;\n}\n<\/style>\n<span  class='av_font_icon av-mqde7m-1-8d1f54c507518a6285e604bf266568af avia_animate_when_visible av-icon-style- avia-icon-pos-left avia-icon-animate'><span class='av-icon-char' aria-hidden='true' data-av_icon='\ue857' data-av_iconfont='entypo-fontello' ><\/span><\/span><\/span><\/span><\/strong>Using the Raman thermometry method, we were able to measure the thermal conductivity of GeSbTe as a function of temperature and its crystallization state. The method uses the measurement of the Raman scattering spectrum, an actual fingerprint of the material that reveals information about its composition and phase. Certain scattering peaks depend on the local temperature and are veritable thermometers that we can calibrate to measure the heating of the material, without contact, using a laser. By analyzing this heating as a function of laser power, we can deduce thermal conductivity.<\/p>\n<p><strong><span style=\"color: #ff7b00;\"><span style=\"color: #008080;\">\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-mqde7m-1-1-075884c2028750bba65b58595eb0da90\">\n.av_font_icon.av-mqde7m-1-1-075884c2028750bba65b58595eb0da90{\ncolor:#991f0f;\nborder-color:#991f0f;\n}\n.av_font_icon.av-mqde7m-1-1-075884c2028750bba65b58595eb0da90 .av-icon-char{\nfont-size:25px;\nline-height:25px;\n}\n<\/style>\n<span  class='av_font_icon av-mqde7m-1-1-075884c2028750bba65b58595eb0da90 avia_animate_when_visible av-icon-style- avia-icon-pos-left avia-icon-animate'><span class='av-icon-char' aria-hidden='true' data-av_icon='\ue889' data-av_iconfont='entypo-fontello' ><\/span><\/span><\/span><\/span><span lang=\"EN-US\">The advantage of this technique lies in the fact that it allows us to obtain thermal and structural information simultaneously. This study, published in the <i>Journal of Applied Physics<\/i>, paves the way for the analysis of many other materials used in memories, telecommunications, optics, detectors and many other applications. <\/span><\/strong><\/p>\n<hr \/>\n<p><strong><span style=\"color: #991f0f;\"><span style=\"color: #ff7b00;\"><span style=\"color: #008080;\">\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-mqde7m-2-1-155984a02432d325023e8dd302db13d2\">\n.av_font_icon.av-mqde7m-2-1-155984a02432d325023e8dd302db13d2{\ncolor:#991f0f;\nborder-color:#991f0f;\n}\n.av_font_icon.av-mqde7m-2-1-155984a02432d325023e8dd302db13d2 .av-icon-char{\nfont-size:25px;\nline-height:25px;\n}\n<\/style>\n<span  class='av_font_icon av-mqde7m-2-1-155984a02432d325023e8dd302db13d2 avia_animate_when_visible av-icon-style- avia-icon-pos-left avia-icon-animate'><span class='av-icon-char' aria-hidden='true' data-av_icon='\ue843' data-av_iconfont='entypo-fontello' ><\/span><\/span><\/span><\/span>Reference:<\/span><\/strong><br \/>\n<strong><em>Thermal characterization of Ge-rich GST thin films for phase change memories by Raman thermometry.<\/em><\/strong><br \/>\n<em> Akash Patil, Yannick Le-Friec, Pascal Roussel, Yves Deblock, Simon Jeannot, Philippe Boivin, Emmanuel Dubois et Jean-Fran\u00e7ois Robillard<\/em><br \/>\n<em> Journal of Applied Physics 136, 175102 (2024).<\/em><br \/>\n<a href=\"https:\/\/doi.org\/10.1063\/5.0226265\" target=\"_blank\" rel=\"noopener\"><em> https:\/\/doi.org\/10.1063\/5.0226265<\/em><\/a><br \/>\n<a href=\"https:\/\/hal.science\/hal-04764747v1\" target=\"_blank\" rel=\"noopener\"><em>https:\/\/hal.science\/hal-04764747v1<\/em><\/a><\/p>\n<hr \/>\n<div  class='avia-button-wrap av-rpqvoq-430fa6c1ae3fe804e22b0967f19a80d0-wrap avia-button-center  avia-builder-el-15  el_after_av_font_icon  avia-builder-el-last'><a href='mailto:jean-francois.robillard@iemn.fr'  class='avia-button av-rpqvoq-430fa6c1ae3fe804e22b0967f19a80d0 av-link-btn avia-icon_select-yes-left-icon avia-size-light avia-position-center avia-color-red'   aria-label=\"Jean-Francois Robillard\"><span class='avia_button_icon avia_button_icon_left' aria-hidden='true' data-av_icon='\ue805' data-av_iconfont='entypo-fontello'><\/span><span class='avia_iconbox_title' >Jean-Francois Robillard<\/span><\/a><\/div>\n<\/div><\/section><\/div>","protected":false},"excerpt":{"rendered":"","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[297],"tags":[],"class_list":["post-72707","post","type-post","status-publish","format-standard","hentry","category-newsletter"],"_links":{"self":[{"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/posts\/72707","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/comments?post=72707"}],"version-history":[{"count":0,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/posts\/72707\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/media?parent=72707"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/categories?post=72707"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/tags?post=72707"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}