{"id":170,"date":"2009-01-28T15:04:40","date_gmt":"2009-01-28T23:04:40","guid":{"rendered":"http:\/\/betasights.net\/wordpress\/?p=170"},"modified":"2009-01-29T12:48:12","modified_gmt":"2009-01-29T20:48:12","slug":"silicon-clocks-embeds-mems-on-cmos","status":"publish","type":"post","link":"http:\/\/www.betasights.net\/wordpress\/?p=170","title":{"rendered":"Silicon Clocks embeds MEMS on CMOS"},"content":{"rendered":"

Silicon Clocks<\/a>, the developer of custom semiconductor timing solutions that has reinvented itself as a “custom product development house” with a new CEO<\/a>, has announced a new product based on its CMOS-MEMS (CMEMS) embedded approach. CMEMS-ZeroThermal passive temperature compensation resonators<\/a> exhibit comparable temperature stability to quartz crystals, while drastically simplifying oscillator design, and reportedly reducing power and circuit size. Company CEO Didier Lacroix told BetaSights to expect more CMEMS technology announcements in the near future.<\/p>\n

Silicon Clocks has developed a <400\u00b0C surface-micromachining flow to create SiGe MEMS, so that these structures may be embedded on chip directly over CMOS metallization (see Figure). The flow starts by making connection to the last level of CMOS metal, much like a redistribution layer (RDL) module:<\/p>\n

\"MEMS<\/a>

MEMS resonator over CMOS (source: Silicon Clocks)<\/p><\/div>\n

1) Connection to CMOS,
\n2) Deposition of sacrificial Ge,
\n3) Deposition of 2\u00b5m SiGe,
\n4) MEMS lithography,
\n5) Sacrificial material removal, and
\n6) Capping process.
\n\u201cWhen you add it all up it\u2019s seven new masks in total; five for the MEMS and two for the cap,\u201d explained Lacroix. \u201cReally what\u2019s different is depositing the SiGe instead of poly.\u201d<\/p>\n

Customers could do these additional steps at their existing fab line, or could send wafers post-CMOS to a different line depending upon the volume requirements. Other non-quartz-crystal timing companies\u2014such as SiTime<\/a> and MobiusMicrosystems<\/a>\u2014offer stand alone single-chip but not embedded solutions. This technology has reportedly been demonstrated across a wide range of resonator designs from the low kilohertz to several hundred megahertz. Silicon Clocks did their alpha and beta development at SVTC. \u201cSVTC has the capabilities for production, so we consider them to have been our beta,\u201d said Lacroix. SVTC announced major investment last year in 200mm wafer tools to be able to provide a MEMS pilot line<\/a>, including many tools from SUSS<\/a> and a Lam etcher<\/a>.<\/p>\n

First-generation MEMS oscillators typically showed 15-30ppm\/\u00b0C variation with temperature, compared to quartz crystals in the 0.25-1.0ppm\/\u00b0C range. Matt Hopcroft<\/a> did excellent Ph.D. work on MEMS resonators, and his 2007 thesis is very worth reading<\/a>. \u201cUntil now, MEMS technology could not compete for ultra-low-power sleep clock applications,\u201d said Lacroix. The company\u2019s completely passive (zero power; no dedicated electronic circuitry) mechanical temperature compensation method is what allows this MEMS technology to match quartz-crystal performance. \u2013E.K.<\/em><\/p>\n","protected":false},"excerpt":{"rendered":"

Silicon Clocks, the developer of custom semiconductor timing solutions that has reinvented itself as a “custom product development house” with a new CEO, has announced a new product based on its CMOS-MEMS (CMEMS) embedded approach. CMEMS-ZeroThermal passive temperature compensation resonators exhibit comparable temperature stability to quartz crystals, while drastically simplifying oscillator design, and reportedly reducing […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9,3,4,6,8],"tags":[122,36,126,89,124,468,125,127,123],"class_list":["post-170","post","type-post","status-publish","format-standard","hentry","category-equipment","category-manufacturing-fabrication-line","category-integrated-circuit","category-micro-electro-mechanical-system","category-market-segment","tag-clock","tag-cmos","tag-crystal","tag-integration","tag-ip","tag-micro-electro-mechanical-system","tag-resonator","tag-si","tag-sige"],"_links":{"self":[{"href":"http:\/\/www.betasights.net\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/170","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.betasights.net\/wordpress\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.betasights.net\/wordpress\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.betasights.net\/wordpress\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.betasights.net\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=170"}],"version-history":[{"count":14,"href":"http:\/\/www.betasights.net\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/170\/revisions"}],"predecessor-version":[{"id":186,"href":"http:\/\/www.betasights.net\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/170\/revisions\/186"}],"wp:attachment":[{"href":"http:\/\/www.betasights.net\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=170"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.betasights.net\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=170"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.betasights.net\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=170"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}