The humble mineral that transformed the world
The semiconductor chip has gone further than any other technology in connecting the world.
How did the chip come to reach every corner of our lives?
From cities that never sleep to remote rural villages, one technology is changing how we live and work. From the smartphones in our pockets to the vast data centres powering the internet, from electric scooters to hypersonic aircraft, pacemakers to weather-predicting supercomputers – inside every one of them, unseen and unsung, are tiny pieces of tech that make it all possible: semiconductors.
These are the basic building blocks of modern computation. Semiconductor devices called transistors are the tiny electronic switches that run computations inside our computers. Scientists in the US built the first silicon transistor in 1947. Before that, the mechanics of computing had been performed by vacuum tubes, which were slow and bulky. Silicon changed everything.
Manufacturing transistors out of silicon allowed them to be made small enough to fit on a microchip, opening the gates to a rush of gadgets that have become smaller and smarter by the year. “Being able to miniaturise these transistors allows us to do things we couldn’t have imagined in previous generations,” says John Neuffer, chief executive of the Semiconductor Industry Association. “All because we can put a massive computer onto a tiny chip.”
The pace of innovation was unprecedented. Chips began to be miniaturised at such a steady rate it was as if the technology was following a law. First stated about 50 years ago by Gordon Moore, co-founder of microchip giant Intel, Moore’s Law predicted that the number of transistors that you could fit on a chip would double every two years.
Until very recently, Moore’s Law was proved right. Only now, when attempts to shrink transistors any smaller are bumping up against the limits of physics, has the pace of miniaturisation slowed. Early transistors could be seen with the naked eye. Now a tiny chip holds many billions of them. More than anything else, it is this exponential improvement in manufacturing that has driven the digital revolution.
But silicon, the element at the heart of this revolution is a surprisingly humble substance, and one of the most common on the planet. Silicon is found in minerals that make up 90% of the Earth’s crust. A technology that has spread across the world is made from one of the most ubiquitous substances on it.
Silicon feeds a $500bn (£410bn) chip industry that in turn powers a global tech economy worth an estimated $3tn. The semiconductor business has also become one of the most interlinked in history, with raw materials coming from Japan and Mexico and chips made in the US and China. The chips are then shipped around the world again to be installed in devices that end up in people’s hands in every country in the world.
“The silicon that is the essence of these chips probably goes around the world two or three times,” says Neuffer. But that vast worldwide network can trace its origins to just a handful of very specific places.
High-end electronics require high-quality ingredients. The purest silicon is found in quartz rock and the purest quartz in the world comes from a quarry near Spruce Pine in North Carolina, US. Millions of the digital devices around the world – perhaps even the phone in your hand or the laptop in front of you – carry a piece of this small North Carolina town inside them. “It does boggle the mind a bit to consider that inside nearly every cell phone and computer chip you’ll find quartz from Spruce Pine,” says Rolf Pippert, mine manager at Quartz Corp, a leading supplier of high-quality quartz.
The rocks around Spruce Pine are unique. High in silica, a silicon-containing compound, and low in contaminates, the region has been mined for centuries for gemstones and mica, a silicate used in paint. But the unearthed quartz was discarded. Then came the rise of the semiconductor industry in the 1980s and quartz turned into white gold.
Now, it sells for $10,000 (£8,250) a tonne, making the Spruce Pine mine a $300m-a-year operation. Rocks extracted from the ground with machines and explosives are put into a crusher, which spits out quartz gravel. This then goes to a processing plant, where the quartz is ground down to a fine sand. Water and chemicals are added to separate the silicon from other minerals. The silicon goes through a final milling before being bagged up and sent as a powder to a refinery.
For all the many billions of microchips in the world, only around 30,000 tonnes of silicon is mined each year. That’s less than the amount of construction sand produced each hour in the US alone. “The reserves here in the Spruce Pine area are very strong,” says Pippert. “We have decades of material. The industry will probably change before we run out of quartz.”
To turn silicon powder into chips, the material is melted in a furnace at 1,400C and formed into cylindrical ingots. These are then sliced into discs called wafers, like chopping up a cucumber. Finally, several dozen rectangular circuits – the chips themselves – are printed onto each wafer in factories, such as that run by Global Foundries in New York State. From here, chips make their way to every corner of the planet.
“We are basically a printing press for any [electronic] device that any company would want to make,” says Chris Belfi, a clean-room engineer at Global Foundries.
Chips are so tiny that dust particles or hairs can ruin their complex circuitry. To avoid contaminating the microelectronics, the vast factory floor must be sterile. An area the size of six football fields is kept thousands of times cleaner than an operating theatre and lit by a dim yellow light to prevent ultraviolet radiation from damaging some of the chemicals used in the production process. Lab workers and factory technicians conduct their business in an eerie glow, clad head to toe in white containment suits complete with masks and goggles.
Inside the clean room, most operations are carried out automatically by vacuum-sealed robots, with parts whizzing between them on ceiling-mounted monorails. Depending on the design, each chip might require anywhere between 1,000 and 2,000 steps to produce it.
The blank wafers that enter the factory floor cost a couple of hundred dollars apiece. When they leave, printed with billions of transistors, they are worth a hundred times more. Most of the chips Global Foundries makes end up in phones or specialist pieces of hardware called GPUs, which power video games, AI and cryptocurrency mining. Connected devices from fitness trackers to smart fridges and smart speakers – collectively known as the internet of things – are another growing family of end devices. “People want more things connected at all times,” says Belfi.
The next stage of the journey is shipping to electronics manufacturers, often overseas. “I feel extremely proud of being part of an industry that has contributed to increasing the level of connectivity between people around the world,” says Isabelle Ferain, director of central engineering at Global Foundries. “When I look at the electronic devices that we use every day, I can see the technology that we’ve worked on.”
After planes, cars and oil, semiconductors are the US’s fourth largest export. Much of the revenue goes back into developing new products, putting the semiconductor industry on a par with pharmaceuticals as a top research-based industry. “We are changing the industry that’s changing the world,” says Ferain.
It is no surprise that chip manufacturers guard their trade secrets closely. “Intellectual property is the lifeblood of the semiconductor industry,” says the Semiconductor Industry Association’s John Neuffer.
But other countries are working hard to catch up. China is the world’s largest consumer of semiconductors but only a small proportion of the chips it uses are homemade. In 2017, China imported $260bn (¥1,800bn; £210bn) worth, the country’s largest single import. It aims to be more self-sufficient, with the ambitious target of producing 40% of its own semiconductors by 2020 and 70% by 2025. A growing number of Chinese firms are producing their own chip designs
As semiconductors have become smaller and cheaper they have become available to almost everyone. It is estimated that more than 5 billion people have mobile devices, and more than half of these are smartphones. And developing countries are now catching up.
According to surveys conducted by Research ICT Africa, a think tank focused on technology policy, the number of people aged 15 years and above in Africa who use the internet has increased from 15% in 2007 to 28% in 2017. Around two in 10 Africans now own a smartphone. “This is mainly attributed to a rapid adoption of cheaper internet-enabled devices,” says Anri van der Spuy at Research ICT Africa.
That means the impact of these technologies is now being felt even in the most rural places. Take Douglas Wanjala, a farmer in Nanyuki, a market town in Kenya, who uses a smartphone to help find buyers for his crops. “The phone has made my job very easy,” he says.
Wanjala and his wife Gladys run a small business growing maize and potatoes on a plot of land near a river next to their home. Before he got a smartphone, the only way Wanjala could sell his crops was to take them to the market. If they didn’t sell, the produce would spoil and he would lose money. Mobile technology lets him cut out that risk. By sharing photos of his crops with potential buyers, he can negotiate a deal before his maize or potatoes are out of the ground. The buyers then come and pick up the crop themselves, rather than waiting for Wanjala to take it to market, receiving it while it is still fresh. Before he had a smartphone he had a hard time marketing his crops, he says.
Wanjala bought his phone for about 15,000 Kenyan shillings (£120) as a business investment. As well as contacting buyers, he uses his phone to keep on top of information vital to running a farm, such as the latest weather forecasts and market prices of different crops. Better access to this information is an effective way to ensure long-term food security in countries such as Kenya and Ethiopia, according to research by Fiona van der Burgt at the global weather organisation Weather Impact. Accessible and accurate weather information gives farmers an edge when deciding what to grow and when to plant it.
To top up his mobile data, Wanjala visits a nearby Wifi hotspot inside a converted shipping container. Away from cities, hubs like this provide a lifeline to local communities. In many countries, there is still a large divide between internet access available to those in cities and those in rural areas. But the trajectory in Sub-Saharan Africa has been promising, with Kenyan farmers becoming frontrunners in taking up mobile technologies to boost their businesses, according to research by Heike Baumüller at the University of Bonn, Germany.
Kenya has the third highest internet use in Africa, with 24% of Kenyans online, according to Research ICT Africa. But other countries are being left behind. For example, in Rwanda, only 9% of people have access to the internet, the lowest number on the continent. What’s more, 77% of those with internet access live in cities.
We need to be careful that this digital divide does not make people worse off, says van der Spuy. “Internet access is now becoming a precondition to participating in societies,” she says. Things like claiming social benefits, applying for jobs or registering children for school are all increasingly done online. And the divide is not only between urban and rural populations. Richer people are more likely to use the internet than poor people, men more likely than women, and young people more likely than old. “If you are not able to use the internet, you thus risk being left further behind.”
As semiconductor technology continues to improve and more people learn digital skills, these gaps should shrink. And smartphones can even boost the overall economy of a country. According to one estimate, for every 10 mobile phones per 100 people in a developing country GDP rises by 0.5%.
Rarely has a single technology had the potential to change the lives of so many. It’s a “pretty awesome” thought, reflects Neuffer, that we have been able to take something as simple as pure quartz sand and turn it into the almost infinitely intricate technology that today connects all our lives.