It is 8 am on Tuesday, and the extreme dilemma that is the SPIE AL Symposium is facing me head on.\u00a0 Where do I go?\u00a0 Do I go to the ASML EUV status talk?\u00a0 Toshiba on the status of nanoimprint for flash manufacturing?\u00a0 Ben Bunday\u2019s review of metrology challenges at 5 nm?\u00a0 Or Moshe Preil\u2019s overview of patterning challenges below 10 nm?\u00a0 Every conference scheduled one of their best talks for first thing in the morning.\u00a0 I chose none of the above and went to the patterning materials conference.\u00a0 What a treat!\u00a0 Six papers in a row full of science, deep dives into mechanisms, data, chemical structures, new measurement approaches, attempts at theoretical explanations, and great discussions.\u00a0 I saw no graphs with missing axes labels, \u201cresist A vs. resist B\u201d comparisons, spin, or marketing pitches.\u00a0 It was what I love most about SPIE.\u00a0 Congratulations to all the authors in that session (and especially the students).<\/p>\n
I did manage to make it to a different Toshiba talk later in the morning on the status of nanoimprint lithography (NIL) development towards manufacturing readiness.\u00a0 Here is the summary.\u00a0 For 2x-nm flash device manufacturing (that is, devices with half-pitch 20-nm and above), defect levels have undergone continuous improvement such that they are confident that all defect specs will be met before the end of this year.\u00a0 According to Toshiba, the only thing prevent NIL from going into manufacturing at these nodes is throughput, which is off by around a factor of 2.\u00a0 Another talk by Canon explained their roadmap for achieving the desired throughput (at least 50-60 wafers per hour for the four-head cluster tool) in the next year by decreasing resist spread time.\u00a0 NIL is extremely close to a go at that node.<\/p>\n
But the value of NIL is not at the 2x-nm flash nodes, where it replaces a mature SADP process.\u00a0 Instead, it is at the 1x-nm node, where it can replace the more expensive and problematic SAQP.\u00a0 There, much more work needs to be done.\u00a0 Defect levels are much too high, both on the as-manufactured templates and during wafer processing.\u00a0 Progress is also being made here, but two-three more years will be required at the least, I suspect.<\/p>\n
I enjoyed a presentation by Gian Lorusso of Imec on attempts to validate LER\/LWR metrology accuracy.\u00a0 What I got out of the talk was basically this:\u00a0 it is really, really hard.\u00a0 We know about the many problems of LER measurements using SEMs, but measurements using TEM or AFM are even worse.\u00a0 Today, we have no alternative but to use our top-down SEM, which means we need to be much more careful about characterizing biases in those measurements and analyzing the data in the most rigorous way possible.<\/p>\n
(An aside to all users of LER metrology:\u00a0 you haven\u2019t measured LER or LWR until you report not just sigma, but the correlation length and roughness exponent as well.\u00a0 You have no excuse \u2013 just do it.)<\/p>\n
By the end of a long day I participated in a panel discussion celebrating the 30-year history of the metrology conference.\u00a0 I have a simple rule for evening panel discussions:\u00a0 if they are not fun, don\u2019t bother.\u00a0 This one was fun \u2013 thank you Ofer Adan.\u00a0 The champagne helped as well.\u00a0 Next week, I\u2019ll try to post my 7-minute talk on the philosophy of metrology.<\/p>\n
As a final note for day two, I\u2019ve had a number of people ask me if my skeptical attitude towards the ultimate manufacturing success of EUV lithography has changed.\u00a0 There has been good progress made in the last year.\u00a0 The 80W tools in the field have finally become reliable enough to allow engineering development.\u00a0 Everyone is talking about ASML\u2019s 200W demonstration.\u00a0 These are all impressive achievements.\u00a0 But my skepticism remains.\u00a0 Source power in the field is still just 80W (will we exceed 100W by the end of the year?).\u00a0 Throughput in the field is enough to peel another layer of the onion and find several more problems with EUV (see yesterday\u2019s post).\u00a0 And there are many more onion layers to go, with problems as yet undiscovered.\u00a0 All of these things take time, and time is the enemy of EUV lithography.\u00a0 EUV has missed the 10-nm node at all companies, and will almost surely miss the 7-nm node at all companies as well.\u00a0 Will it be ready for the 5-nm node?\u00a0 A 5-nm node that must be relaxed to accommodate the resolution limits of single patterning EUVL?\u00a0 Will any fab be able to make money at 5 nm, with or without EUV?\u00a0 My skepticism remains.<\/p>\n","protected":false},"excerpt":{"rendered":"
It is 8 am on Tuesday, and the extreme dilemma that is the SPIE AL Symposium is facing me head on.\u00a0 Where do I go?\u00a0 Do I go to the ASML EUV status talk?\u00a0 Toshiba on the status of nanoimprint for flash manufacturing?\u00a0 Ben Bunday\u2019s review of metrology challenges at 5 nm?\u00a0 Or Moshe Preil\u2019s […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[],"class_list":["post-482","post","type-post","status-publish","format-standard","hentry","category-microlithography"],"_links":{"self":[{"href":"https:\/\/lithoguru.com\/life\/index.php?rest_route=\/wp\/v2\/posts\/482","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/lithoguru.com\/life\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/lithoguru.com\/life\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/lithoguru.com\/life\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/lithoguru.com\/life\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=482"}],"version-history":[{"count":1,"href":"https:\/\/lithoguru.com\/life\/index.php?rest_route=\/wp\/v2\/posts\/482\/revisions"}],"predecessor-version":[{"id":483,"href":"https:\/\/lithoguru.com\/life\/index.php?rest_route=\/wp\/v2\/posts\/482\/revisions\/483"}],"wp:attachment":[{"href":"https:\/\/lithoguru.com\/life\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=482"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/lithoguru.com\/life\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=482"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/lithoguru.com\/life\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=482"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}