1 00:00:01,246 --> 00:00:04,830 Computers used to be as big as a room. 2 00:00:04,854 --> 00:00:06,446 But now they fit in your pocket, 3 00:00:06,470 --> 00:00:07,641 on your wrist 4 00:00:07,665 --> 00:00:10,984 and can even be implanted inside of your body. 5 00:00:11,008 --> 00:00:12,289 How cool is that? 6 00:00:12,809 --> 00:00:17,146 And this has been enabled by the miniaturization of transistors, 7 00:00:17,170 --> 00:00:19,662 which are the tiny switches in the circuits 8 00:00:19,686 --> 00:00:21,462 at the heart of our computers. 9 00:00:22,051 --> 00:00:25,223 And it's been achieved through decades of development 10 00:00:25,247 --> 00:00:28,045 and breakthroughs in science and engineering 11 00:00:28,069 --> 00:00:30,741 and of billions of dollars of investment. 12 00:00:31,352 --> 00:00:34,100 But it's given us vast amounts of computing, 13 00:00:34,124 --> 00:00:35,929 huge amounts of memory 14 00:00:35,953 --> 00:00:40,895 and the digital revolution that we all experience and enjoy today. 15 00:00:41,665 --> 00:00:44,433 But the bad news is, 16 00:00:44,457 --> 00:00:47,589 we're about to hit a digital roadblock, 17 00:00:47,613 --> 00:00:51,963 as the rate of miniaturization of transistors is slowing down. 18 00:00:52,471 --> 00:00:55,345 And this is happening at exactly the same time 19 00:00:55,369 --> 00:00:59,367 as our innovation in software is continuing relentlessly 20 00:00:59,391 --> 00:01:03,151 with artificial intelligence and big data. 21 00:01:03,175 --> 00:01:08,215 And our devices regularly perform facial recognition or augment our reality 22 00:01:08,239 --> 00:01:12,464 or even drive cars down our treacherous, chaotic roads. 23 00:01:12,959 --> 00:01:14,166 It's amazing. 24 00:01:14,618 --> 00:01:19,285 But if we don't keep up with the appetite of our software, 25 00:01:19,309 --> 00:01:23,096 we could reach a point in the development of our technology 26 00:01:23,120 --> 00:01:27,330 where the things that we could do with software could, in fact, be limited 27 00:01:27,354 --> 00:01:28,625 by our hardware. 28 00:01:29,075 --> 00:01:33,583 We've all experienced the frustration of an old smartphone or tablet 29 00:01:33,607 --> 00:01:36,771 grinding slowly to a halt over time 30 00:01:36,795 --> 00:01:40,770 under the ever-increasing weight of software updates and new features. 31 00:01:40,794 --> 00:01:44,177 And it worked just fine when we bought it not so long ago. 32 00:01:44,201 --> 00:01:48,711 But the hungry software engineers have eaten up all the hardware capacity 33 00:01:48,735 --> 00:01:50,041 over time. 34 00:01:51,883 --> 00:01:55,495 The semiconductor industry is very well aware of this 35 00:01:55,519 --> 00:01:59,403 and is working on all sorts of creative solutions, 36 00:01:59,427 --> 00:02:03,738 such as going beyond transistors to quantum computing 37 00:02:03,762 --> 00:02:07,974 or even working with transistors in alternative architectures 38 00:02:07,998 --> 00:02:09,601 such as neural networks 39 00:02:09,625 --> 00:02:12,638 to make more robust and efficient circuits. 40 00:02:13,270 --> 00:02:16,609 But these approaches will take quite some time, 41 00:02:16,633 --> 00:02:21,260 and we're really looking for a much more immediate solution to this problem. 42 00:02:22,899 --> 00:02:27,681 The reason why the rate of miniaturization of transistors is slowing down 43 00:02:27,705 --> 00:02:32,391 is due to the ever-increasing complexity of the manufacturing process. 44 00:02:33,142 --> 00:02:36,392 The transistor used to be a big, bulky device, 45 00:02:36,416 --> 00:02:39,725 until the invent of the integrated circuit 46 00:02:39,749 --> 00:02:42,440 based on pure crystalline silicon wafers. 47 00:02:42,946 --> 00:02:45,725 And after 50 years of continuous development, 48 00:02:45,749 --> 00:02:49,122 we can now achieve transistor features dimensions 49 00:02:49,146 --> 00:02:51,675 down to 10 nanometers. 50 00:02:52,361 --> 00:02:54,798 You can fit more than a billion transistors 51 00:02:54,822 --> 00:02:57,785 in a single square millimeter of silicon. 52 00:02:58,273 --> 00:03:00,295 And to put this into perspective: 53 00:03:00,319 --> 00:03:04,145 a human hair is 100 microns across. 54 00:03:04,169 --> 00:03:06,688 A red blood cell, which is essentially invisible, 55 00:03:06,712 --> 00:03:08,311 is eight microns across, 56 00:03:08,335 --> 00:03:11,735 and you can place 12 across the width of a human hair. 57 00:03:12,467 --> 00:03:15,567 But a transistor, in comparison, is much smaller, 58 00:03:15,591 --> 00:03:19,439 at a tiny fraction of a micron across. 59 00:03:19,463 --> 00:03:23,009 You could place more than 260 transistors 60 00:03:23,033 --> 00:03:25,011 across a single red blood cell 61 00:03:25,035 --> 00:03:29,499 or more than 3,000 across the width of a human hair. 62 00:03:29,523 --> 00:03:33,847 It really is incredible nanotechnology in your pocket right now. 63 00:03:35,204 --> 00:03:37,392 And besides the obvious benefit 64 00:03:37,416 --> 00:03:41,250 of being able to place more, smaller transistors on a chip, 65 00:03:41,984 --> 00:03:45,476 smaller transistors are faster switches, 66 00:03:46,166 --> 00:03:50,567 and smaller transistors are also more efficient switches. 67 00:03:50,591 --> 00:03:53,068 So this combination has given us 68 00:03:53,092 --> 00:03:57,391 lower cost, higher performance and higher efficiency electronics 69 00:03:57,415 --> 00:03:59,478 that we all enjoy today. 70 00:04:02,415 --> 00:04:05,179 To manufacture these integrated circuits, 71 00:04:05,203 --> 00:04:08,411 the transistors are built up layer by layer, 72 00:04:08,435 --> 00:04:10,788 on a pure crystalline silicon wafer. 73 00:04:11,332 --> 00:04:13,560 And in an oversimplified sense, 74 00:04:13,584 --> 00:04:17,865 every tiny feature of the circuit is projected 75 00:04:17,889 --> 00:04:20,221 onto the surface of the silicon wafer 76 00:04:20,245 --> 00:04:23,924 and recorded in a light-sensitive material 77 00:04:23,948 --> 00:04:26,887 and then etched through the light-sensitive material 78 00:04:26,911 --> 00:04:29,932 to leave the pattern in the underlying layers. 79 00:04:30,612 --> 00:04:34,696 And this process has been dramatically improved over the years 80 00:04:34,720 --> 00:04:37,493 to give the electronics performance we have today. 81 00:04:38,279 --> 00:04:41,721 But as the transistor features get smaller and smaller, 82 00:04:41,745 --> 00:04:44,782 we're really approaching the physical limitations 83 00:04:44,806 --> 00:04:46,689 of this manufacturing technique. 84 00:04:48,515 --> 00:04:51,620 The latest systems for doing this patterning 85 00:04:51,644 --> 00:04:53,947 have become so complex 86 00:04:53,971 --> 00:04:58,701 that they reportedly cost more than 100 million dollars each. 87 00:04:58,725 --> 00:05:03,012 And semiconductor factories contain dozens of these machines. 88 00:05:03,036 --> 00:05:07,462 So people are seriously questioning: Is this approach long-term viable? 89 00:05:08,441 --> 00:05:12,121 But we believe we can do this chip manufacturing 90 00:05:12,145 --> 00:05:16,168 in a totally different and much more cost-effective way 91 00:05:16,966 --> 00:05:20,939 using molecular engineering and mimicking nature 92 00:05:20,963 --> 00:05:24,576 down at the nanoscale dimensions of our transistors. 93 00:05:25,267 --> 00:05:29,928 As I said, the conventional manufacturing takes every tiny feature of the circuit 94 00:05:29,952 --> 00:05:32,076 and projects it onto the silicon. 95 00:05:32,818 --> 00:05:35,562 But if you look at the structure of an integrated circuit, 96 00:05:35,586 --> 00:05:37,560 the transistor arrays, 97 00:05:37,584 --> 00:05:41,213 many of the features are repeated millions of times. 98 00:05:41,237 --> 00:05:43,845 It's a highly periodic structure. 99 00:05:44,331 --> 00:05:47,399 So we want to take advantage of this periodicity 100 00:05:47,423 --> 00:05:50,120 in our alternative manufacturing technique. 101 00:05:50,144 --> 00:05:53,579 We want to use self-assembling materials 102 00:05:53,603 --> 00:05:56,580 to naturally form the periodic structures 103 00:05:56,604 --> 00:05:58,987 that we need for our transistors. 104 00:06:00,052 --> 00:06:02,194 We do this with the materials, 105 00:06:02,218 --> 00:06:05,655 then the materials do the hard work of the fine patterning, 106 00:06:05,679 --> 00:06:10,538 rather than pushing the projection technology to its limits and beyond. 107 00:06:11,909 --> 00:06:15,808 Self-assembly is seen in nature in many different places, 108 00:06:15,832 --> 00:06:19,242 from lipid membranes to cell structures, 109 00:06:19,266 --> 00:06:22,321 so we do know it can be a robust solution. 110 00:06:22,345 --> 00:06:25,906 If it's good enough for nature, it should be good enough for us. 111 00:06:26,549 --> 00:06:31,349 So we want to take this naturally occurring, robust self-assembly 112 00:06:31,373 --> 00:06:35,338 and use it for the manufacturing of our semiconductor technology. 113 00:06:36,929 --> 00:06:39,544 One type of self-assemble material -- 114 00:06:40,388 --> 00:06:42,635 it's called a block co-polymer -- 115 00:06:42,659 --> 00:06:47,442 consists of two polymer chains just a few tens of nanometers in length. 116 00:06:47,466 --> 00:06:49,517 But these chains hate each other. 117 00:06:49,541 --> 00:06:51,025 They repel each other, 118 00:06:51,049 --> 00:06:54,946 very much like oil and water or my teenage son and daughter. 119 00:06:54,970 --> 00:06:56,327 (Laughter) 120 00:06:56,351 --> 00:06:59,125 But we cruelly bond them together, 121 00:06:59,149 --> 00:07:01,844 creating an inbuilt frustration in the system, 122 00:07:01,868 --> 00:07:04,074 as they try to separate from each other. 123 00:07:04,716 --> 00:07:08,001 And in the bulk material, there are billions of these, 124 00:07:08,025 --> 00:07:11,326 and the similar components try to stick together, 125 00:07:11,350 --> 00:07:14,159 and the opposing components try to separate from each other 126 00:07:14,183 --> 00:07:15,338 at the same time. 127 00:07:15,362 --> 00:07:19,116 And this has a built-in frustration, a tension in the system, 128 00:07:19,140 --> 00:07:23,449 so it moves around, it squirms until a shape is formed. 129 00:07:24,209 --> 00:07:28,257 And the natural self-assembled shape that is formed is nanoscale, 130 00:07:28,281 --> 00:07:32,008 it's regular, it's periodic, and it's long range, 131 00:07:32,032 --> 00:07:35,890 which is exactly what we need for our transistor arrays. 132 00:07:37,347 --> 00:07:39,878 So we can use molecular engineering 133 00:07:39,902 --> 00:07:42,966 to design different shapes of different sizes 134 00:07:42,990 --> 00:07:45,053 and of different periodicities. 135 00:07:45,077 --> 00:07:47,808 So for example, if we take a symmetrical molecule, 136 00:07:47,832 --> 00:07:50,907 where the two polymer chains are similar length, 137 00:07:50,931 --> 00:07:53,602 the natural self-assembled structure that is formed 138 00:07:53,626 --> 00:07:56,555 is a long, meandering line, 139 00:07:56,579 --> 00:07:58,389 very much like a fingerprint. 140 00:07:58,951 --> 00:08:01,273 And the width of the fingerprint lines 141 00:08:01,297 --> 00:08:03,307 and the distance between them 142 00:08:03,331 --> 00:08:07,242 is determined by the lengths of our polymer chains 143 00:08:07,266 --> 00:08:10,560 but also the level of built-in frustration in the system. 144 00:08:11,320 --> 00:08:13,878 And we can even create more elaborate structures 145 00:08:15,487 --> 00:08:17,926 if we use unsymmetrical molecules, 146 00:08:18,839 --> 00:08:22,924 where one polymer chain is significantly shorter than the other. 147 00:08:23,749 --> 00:08:26,459 And the self-assembled structure that forms in this case 148 00:08:26,483 --> 00:08:30,283 is with the shorter chains forming a tight ball in the middle, 149 00:08:30,307 --> 00:08:34,148 and it's surrounded by the longer, opposing polymer chains, 150 00:08:34,172 --> 00:08:36,220 forming a natural cylinder. 151 00:08:37,089 --> 00:08:39,164 And the size of this cylinder 152 00:08:39,188 --> 00:08:42,603 and the distance between the cylinders, the periodicity, 153 00:08:42,627 --> 00:08:46,221 is again determined by how long we make the polymer chains 154 00:08:46,245 --> 00:08:48,983 and the level of built-in frustration. 155 00:08:49,896 --> 00:08:53,774 So in other words, we're using molecular engineering 156 00:08:53,798 --> 00:08:56,623 to self-assemble nanoscale structures 157 00:08:56,647 --> 00:09:01,557 that can be lines or cylinders the size and periodicity of our design. 158 00:09:02,369 --> 00:09:05,666 We're using chemistry, chemical engineering, 159 00:09:05,690 --> 00:09:10,479 to manufacture the nanoscale features that we need for our transistors. 160 00:09:13,611 --> 00:09:17,660 But the ability to self-assemble these structures 161 00:09:17,684 --> 00:09:20,121 only takes us half of the way, 162 00:09:20,145 --> 00:09:22,954 because we still need to position these structures 163 00:09:22,978 --> 00:09:26,528 where we want the transistors in the integrated circuit. 164 00:09:27,246 --> 00:09:29,984 But we can do this relatively easily 165 00:09:30,008 --> 00:09:36,985 using wide guide structures that pin down the self-assembled structures, 166 00:09:37,009 --> 00:09:38,930 anchoring them in place 167 00:09:38,954 --> 00:09:41,801 and forcing the rest of the self-assembled structures 168 00:09:41,825 --> 00:09:43,175 to lie parallel, 169 00:09:43,199 --> 00:09:45,599 aligned with our guide structure. 170 00:09:46,510 --> 00:09:51,149 For example, if we want to make a fine, 40-nanometer line, 171 00:09:51,173 --> 00:09:55,311 which is very difficult to manufacture with conventional projection technology, 172 00:09:56,274 --> 00:10:01,059 we can manufacture a 120-nanometer guide structure 173 00:10:01,083 --> 00:10:03,587 with normal projection technology, 174 00:10:03,611 --> 00:10:10,202 and this structure will align three of the 40-nanometer lines in between. 175 00:10:10,226 --> 00:10:14,995 So the materials are doing the most difficult fine patterning. 176 00:10:15,790 --> 00:10:19,697 And we call this whole approach "directed self-assembly." 177 00:10:21,586 --> 00:10:24,340 The challenge with directed self-assembly 178 00:10:24,364 --> 00:10:28,840 is that the whole system needs to align almost perfectly, 179 00:10:28,864 --> 00:10:34,145 because any tiny defect in the structure could cause a transistor failure. 180 00:10:34,169 --> 00:10:37,138 And because there are billions of transistors in our circuit, 181 00:10:37,162 --> 00:10:40,390 we need an almost molecularly perfect system. 182 00:10:40,977 --> 00:10:42,982 But we're going to extraordinary measures 183 00:10:43,006 --> 00:10:44,173 to achieve this, 184 00:10:44,197 --> 00:10:47,189 from the cleanliness of our chemistry 185 00:10:47,213 --> 00:10:49,539 to the careful processing of these materials 186 00:10:49,563 --> 00:10:51,134 in the semiconductor factory 187 00:10:51,158 --> 00:10:55,730 to remove even the smallest nanoscopic defects. 188 00:10:57,311 --> 00:11:02,501 So directed self-assembly is an exciting new disruptive technology, 189 00:11:02,525 --> 00:11:05,094 but it is still in the development stage. 190 00:11:05,680 --> 00:11:09,541 But we're growing in confidence that we could, in fact, introduce it 191 00:11:09,565 --> 00:11:11,252 to the semiconductor industry 192 00:11:11,276 --> 00:11:14,233 as a revolutionary new manufacturing process 193 00:11:14,257 --> 00:11:16,324 in just the next few years. 194 00:11:17,014 --> 00:11:20,048 And if we can do this, if we're successful, 195 00:11:20,072 --> 00:11:21,603 we'll be able to continue 196 00:11:21,627 --> 00:11:24,885 with the cost-effective miniaturization of transistors, 197 00:11:24,909 --> 00:11:28,662 continue with the spectacular expansion of computing 198 00:11:28,686 --> 00:11:30,568 and the digital revolution, 199 00:11:30,592 --> 00:11:34,137 and what's more, this could even be the dawn of a new era 200 00:11:34,161 --> 00:11:36,392 of molecular manufacturing. 201 00:11:36,416 --> 00:11:37,947 How cool is that? 202 00:11:38,519 --> 00:11:39,677 Thank you. 203 00:11:39,701 --> 00:11:43,910 (Applause)