WEBVTT 00:00:21.920 --> 00:00:26.079 Pick up your phone, tap the glass. 00:00:26.079 --> 00:00:29.440 It responds flawlessly. 00:00:29.440 --> 00:00:34.240 We communicate through them and they tell us where to drive. 00:00:34.240 --> 00:00:37.200 We use them as flashlights. 00:00:37.200 --> 00:00:43.600 They function so seamlessly that we stop wondering. 00:00:43.600 --> 00:00:48.079 We accept them as polished little black boxes. 00:00:48.079 --> 00:00:57.119 Generally, unless you like to take electronics apart, you don't ever see into your devices. 00:00:57.119 --> 00:00:59.840 But you've heard of Silicon Valley. 00:00:59.840 --> 00:01:03.759 You know there's silicon in there, somewhere. 00:01:03.759 --> 00:01:06.640 And silicon is in sand. 00:01:06.640 --> 00:01:09.200 Quartz sand. 00:01:09.200 --> 00:01:16.799 But you can't shovel sand off the beach and turn it into the hardware that runs your phone. 00:01:16.799 --> 00:01:23.200 The physical reality of the digital world requires us to turn sand into something flawless. 00:01:23.200 --> 00:01:28.400 It requires light that is barely possible. 00:01:28.400 --> 00:01:32.879 And it all started with a mistake. 00:01:32.879 --> 00:01:35.760 I'm Daina Bouquin. 00:01:35.760 --> 00:01:38.959 This is Found in the Machine. 00:01:38.959 --> 00:01:44.560 The year is 1916. 00:01:44.560 --> 00:01:50.879 The world outside is tearing itself apart in the trenches of the First World War. 00:01:50.879 --> 00:01:57.439 But inside a metallurgy laboratory in Berlin, it is quiet. 00:01:57.439 --> 00:02:05.200 Jan Czochralski is working late. A Polish man. 00:02:05.200 --> 00:02:08.159 He is a self-taught chemist. 00:02:08.159 --> 00:02:21.840 He has spent the entire day and most of the evening staring at metals, heating them, cooling them, trying to understand the exact speed at which they crystallize. 00:02:21.840 --> 00:02:27.919 The kind of repetitive observation that blurs the lines of your vision. 00:02:27.919 --> 00:02:31.599 On his desk there is an inkwell. 00:02:31.599 --> 00:02:37.680 Beside it, there is a small crucible left over from a previous experiment. 00:02:37.680 --> 00:02:42.879 It contains a cooling pool of molten tin. 00:02:42.879 --> 00:02:46.479 Jan reaches for his fountain pen. 00:02:46.479 --> 00:02:55.280 Without looking away from his papers in front of him, he dips the nib of the pen, but his hand misjudges the distance. 00:02:55.280 --> 00:02:58.960 He dips the pen into the crucible. 00:02:58.960 --> 00:03:01.840 It goes straight into the liquid tin. 00:03:01.840 --> 00:03:06.000 Realizing his mistake, he quickly pulls the pen upward. 00:03:06.000 --> 00:03:11.680 Then he stops, because something catches the flickering light. 00:03:11.680 --> 00:03:18.560 A silvery, hair-thin, shimmering wire is hanging from the tip of his pen. 00:03:18.560 --> 00:03:22.560 He doesn't just wipe it away. 00:03:22.560 --> 00:03:24.240 He looks. 00:03:24.240 --> 00:03:25.919 He wonders. 00:03:25.919 --> 00:03:29.360 Then he does it again. 00:03:29.360 --> 00:03:36.879 The pen goes back into the tin and slowly, deliberately this time, he pulls it up again. 00:03:36.879 --> 00:03:38.960 The thread grows. 00:03:38.960 --> 00:03:45.439 The tiny slit in his pen's nib is acting like a capillary. 00:03:45.439 --> 00:03:52.960 The liquid metal is being pulled up and is cooling the moment it touches the air, clinging to itself as it rises. 00:03:52.960 --> 00:03:56.879 And this isn't just a wire. 00:03:56.879 --> 00:04:04.400 As Jan pulled the pen, the atoms in the pool of tin didn't scramble into a chaotic jumble as they cooled. 00:04:04.400 --> 00:04:06.560 They aligned. 00:04:06.560 --> 00:04:13.680 This wire is a single, unbroken, continuous crystal lattice. 00:04:13.680 --> 00:04:16.160 It is perfect. 00:04:16.160 --> 00:04:22.720 Jan Czochrolski has just invented a way to grow flawless crystals. 00:04:22.720 --> 00:04:26.240 He wrote a paper about it. 00:04:26.240 --> 00:04:31.439 He called it a new method for measuring the crystallization rate of metals. 00:04:31.439 --> 00:04:35.439 But he had no idea what he had actually done. 00:04:35.439 --> 00:04:37.680 He would never know. 00:04:37.680 --> 00:04:48.399 There are two streams of materials that must collide to make a microchip possible. 00:04:48.399 --> 00:04:52.720 First, there is the silicon that will become the chip itself. 00:04:52.720 --> 00:05:10.160 It begins its life as metallurgical grade silicon, forged by taking high-purity quartz, which is a rock mostly mined in deposits from China, Norway, and Brazil, and throwing it into an electric arc furnace with carbon. 00:05:10.160 --> 00:05:15.040 It is blasted at up to 2,000 degrees Celsius. 00:05:15.040 --> 00:05:24.879 Then it is chemically purified over and over again until it reaches what engineers call the 9N level. 00:05:24.879 --> 00:05:33.920 That's 99.9999999% pure. 00:05:33.920 --> 00:05:39.439 Out of one billion atoms, only one can be an impurity. 00:05:39.439 --> 00:05:45.120 But having the purest liquid silicon on earth is only the first step. 00:05:45.120 --> 00:05:50.079 You also need to hold that perfect liquid without contaminating it. 00:05:50.079 --> 00:05:54.399 You need a very, very special crucible. 00:05:54.399 --> 00:05:59.439 The crucible you need does not come from a global supply chain. 00:05:59.439 --> 00:06:04.959 Overwhelmingly, it comes from a single town in the Blue Ridge Mountains. 00:06:04.959 --> 00:06:08.639 Spruce Pine, North Carolina. 00:06:08.639 --> 00:06:17.279 Through a geological anomaly, Spruce Pine holds the purest natural quartz ever discovered on Earth. 00:06:17.279 --> 00:06:22.560 So you have the ultra-pure silicon gathered from across the globe. 00:06:22.560 --> 00:06:28.959 You have the perfect quartz crucible pulled from the mountains of North Carolina. 00:06:28.959 --> 00:06:35.040 The silicon is molten inside that pristine vessel. 00:06:35.040 --> 00:06:38.079 Now, how do you get it out? 00:06:38.079 --> 00:06:43.920 How do you turn it into a pristine canvas for microchips? 00:06:43.920 --> 00:06:52.319 You use the method that Jan Czochrolski accidentally invented when he was too tired to notice where he put his pen. 00:06:52.319 --> 00:07:04.879 You see, in the late 1940s and early 1950s, as researchers tried to make reliable transistors, they kept running into the same wall. 00:07:04.879 --> 00:07:18.000 They needed perfectly ordered semiconductor material. A single flaw, a single microscopic misalignment in the crystal lattice, and the electrical signals would scatter and fail. 00:07:18.000 --> 00:07:21.120 They needed a perfect canvas. 00:07:21.120 --> 00:07:24.480 And they did not know how to make one. 00:07:24.480 --> 00:07:29.600 Until they found an obscure paper from 1916. 00:07:29.600 --> 00:07:38.480 Today, nearly all silicon wafers on Earth are made using Czochrolski's method, often referred to as the C Z method. 00:07:38.480 --> 00:07:52.079 Inside those ultra-pure Spruce Pine quartz crucibles, we dip a tiny seed of crystal into the molten 9N silicon, and slowly, we pull it upward. 00:07:52.079 --> 00:07:54.879 Spinning as it cools. 00:07:54.879 --> 00:08:05.040 We grow giant, flawless crystal cylinders, hundreds of pounds heavy, atoms aligned in perfect lockstep. 00:08:05.040 --> 00:08:11.360 But Jan did not spend the rest of his life being celebrated for it. 00:08:11.360 --> 00:08:17.600 He left Germany in 1928, returning to a newly independent Poland. 00:08:17.600 --> 00:08:22.160 He became a professor at the Warsaw University of Technology. 00:08:22.160 --> 00:08:26.240 He was a brilliant, wealthy patron of the arts. 00:08:26.240 --> 00:08:29.360 Then came 1939. 00:08:29.360 --> 00:08:31.680 The invasion. 00:08:31.680 --> 00:08:35.919 The universities were violently shut down. 00:08:35.919 --> 00:08:41.840 Academics were arrested, sent to camps, executed. 00:08:41.840 --> 00:08:53.360 Jan, leaning on his pre-war connections in Germany, and his German wife, got permission from the occupying forces to keep his laboratory open. 00:08:53.360 --> 00:08:57.519 He rebranded it as a materials research facility. 00:08:57.519 --> 00:09:04.879 To the people on the street, to his former colleagues, he looked like a collaborator. 00:09:04.879 --> 00:09:10.960 A man who had traded his country's dignity for his own survival. 00:09:10.960 --> 00:09:16.320 But they did not know that the lab was a front. 00:09:16.320 --> 00:09:24.639 Jan was secretly employing members of the Polish resistance, providing them with documents to keep them out of the camps. 00:09:24.639 --> 00:09:31.840 He was using the lab's machinery to reverse engineer German V-1 and V2 rockets. 00:09:31.840 --> 00:09:37.200 He was manufacturing grenade shells for the underground home army. 00:09:37.200 --> 00:09:42.320 His work had the approval of the Polish underground state. 00:09:42.320 --> 00:09:47.120 There's evidence that he sheltered two Jewish women in his own home. 00:09:47.120 --> 00:09:50.480 But he looked like a collaborator. 00:09:50.480 --> 00:09:57.519 And when the war ended, the new communist regime arrested him and tried him for treason. 00:09:57.519 --> 00:09:59.840 He was acquitted. 00:09:59.840 --> 00:10:04.720 An investigation proved that he did not collaborate with the Nazis. 00:10:04.720 --> 00:10:08.000 He had never been a traitor. 00:10:08.000 --> 00:10:11.519 But it did not matter. 00:10:11.519 --> 00:10:14.960 The reputational damage was done. 00:10:14.960 --> 00:10:18.399 He was stripped of his professorship. 00:10:18.399 --> 00:10:24.799 His name was meticulously and deliberately erased from the university's records. 00:10:24.799 --> 00:10:38.320 A man who would later be listed among the fathers of modern electronics died in 1953, running a small operation in his hometown, making cosmetics and sneezing powder. 00:10:38.320 --> 00:10:44.000 Here is what he never saw. 00:10:44.000 --> 00:10:48.639 By the time Jan died, the canvas was solved. 00:10:48.639 --> 00:10:53.039 His crystals would become every microchip we would ever build. 00:10:53.039 --> 00:10:58.240 The brains in every supercomputer, satellite, and smart toaster. 00:10:58.240 --> 00:11:03.360 But you still have to draw the pathways for the electricity to flow. 00:11:03.360 --> 00:11:14.720 In the early days, we drew those pathways using visible light, shining it through a stencil-like mask onto the silicon to etch the circuits. 00:11:14.720 --> 00:11:20.639 But as we demanded smaller and faster machines, the stencils had to shrink. 00:11:20.639 --> 00:11:25.360 Today there are billions of transistors on a single chip. 00:11:25.360 --> 00:11:29.360 Those transistors are only a few nanometers wide. 00:11:29.360 --> 00:11:35.519 Five nanometers is about the length your fingernail grows in five seconds. 00:11:35.519 --> 00:11:39.679 You cannot etch something that small with ordinary light. 00:11:39.679 --> 00:11:43.200 The wavelength of visible light is too wide. 00:11:43.200 --> 00:11:48.960 It is like trying to paint a microscopic masterpiece with a heavy push broom. 00:11:48.960 --> 00:11:56.399 To work at that scale, you need light that is roughly 100 times smaller than visible light. 00:11:56.399 --> 00:12:00.720 You need extreme ultraviolet light. 00:12:00.720 --> 00:12:16.559 The machines that make and harness EUV light are among the most complex devices humanity has ever built. One machine costs hundreds of millions of dollars and contains more than 100,000 parts. 00:12:16.559 --> 00:12:22.720 Inside, EUV light bounces through a series of mirrors before passing through the stencil. 00:12:22.720 --> 00:12:26.399 More mirrors focus it onto the silicon. 00:12:26.399 --> 00:12:37.840 Those mirrors are polished so perfectly that if you expanded one to be the size of Germany, the tallest bump on its surface would be less than a millimeter high. 00:12:37.840 --> 00:12:48.159 Those mirrors a blueprint for billions of transistors onto the silicon that Jan's method grew with unthinkable precision. 00:12:48.159 --> 00:12:54.960 It is akin to standing on Earth and shooting an arrow through an apple on the surface of the moon. 00:12:54.960 --> 00:12:57.120 Then doing it again. 00:12:57.120 --> 00:12:58.639 And again. 00:12:58.639 --> 00:13:04.320 Thousands of chips can be etched onto a single silicon wafer. 00:13:04.320 --> 00:13:07.919 And the light itself does not want to exist. 00:13:07.919 --> 00:13:12.480 Extreme ultraviolet light is swallowed by air. 00:13:12.480 --> 00:13:16.000 It does not occur naturally on Earth. 00:13:16.000 --> 00:13:22.159 So, deep within the EU V machine, there is a vacuum chamber. 00:13:22.159 --> 00:13:29.919 In that airless space, a generator ejects a microscopic droplet of liquid metal into the dark. 00:13:29.919 --> 00:13:31.600 Then another. 00:13:31.600 --> 00:13:36.720 50,000 droplets, every single second. 00:13:36.720 --> 00:13:47.360 As each droplet falls, a high-powered laser fires a weak pulse, just enough to flatten the tiny sphere into a tiny pancake. 00:13:47.360 --> 00:13:54.159 A microsecond later, a second pulse fires with devastating force. 00:13:54.159 --> 00:13:56.240 The metal vaporizes. 00:13:56.240 --> 00:14:01.279 It becomes a plasma burning 40 times hotter than the surface of the sun. 00:14:01.279 --> 00:14:12.240 And in that violent, microscopic death, it flashes, throwing off a burst of extreme ultraviolet light. 00:14:12.240 --> 00:14:18.399 And the metal, the drop that dies in the dark to light the digital age. 00:14:18.399 --> 00:14:20.080 It is tin. 00:14:20.080 --> 00:14:22.879 Molten tin. 00:14:22.879 --> 00:14:37.039 In 1916, a tired man dipped his pen into a crucible of tin and pulled out the foundation of the digital world. 00:14:37.039 --> 00:14:46.960 More than a century later, we blast falling drops of that same metal to make light so fragile it can barely exist. 00:14:46.960 --> 00:14:54.879 That light is used to draw microchips onto the perfect crystals that power our devices. 00:14:54.879 --> 00:15:00.559 And we use those devices as flashlights. 00:15:00.559 --> 00:15:04.879 I'm Daina Bouquin. 00:15:04.879 --> 00:15:08.159 And this is Found in the Machine. 00:15:08.159 --> 00:15:16.159 Before you go, if you'd like to support the show, rate and review this podcast wherever you listen. 00:15:16.159 --> 00:15:18.799 Or better yet, share it with a friend. 00:15:18.799 --> 00:15:24.720 I'm really trying to turn this into something sustainable, and I'd love your help getting the word out. 00:15:24.720 --> 00:15:32.639 Another way you can support the show is by going to bookshop.org/shop/found in the machine. 00:15:33.519 --> 00:15:41.440 Your purchases support independent bookstores across the US, and they also help make this podcast possible. 00:15:41.440 --> 00:15:49.279 And if you'd like to dive deeper into any of these stories, you can sign up for my newsletter at notes.foundinthemachine.com. Thanks for listening.