probably never heard of. TSMC of Taiwan  uses cutting-edge lasers to etch intricate  

details less than a thousandth the size of  a red blood cell onto the purest hunks of  

wafer-thin silicon. All while an army of  super-strong robots zoom around on tracks  

traveling the equivalent of ten times  around the earth every single day.

There's every chance you already have at least  one of its products – integrated circuits,  

better known as 'chips' – in your home or car.

But what's up with the eery yellow lighting  inside? Why are they such neat freaks? And could  

the whole vast enterprise soon be rudely swept  away on a rising tide of geopolitical insecurity?

Join us today as we put on one  of those weird suits and step  

inside the world's largest computer chip factory.

If you were asked at a pub quiz to name  the world's most important chipmaker,  

you'd probably say Intel, AMD, Arm, or Samsung.

Most people have never heard of TSMC, aka  the Taiwan Semiconductor Manufacturing  

Company – and yet it currently controls more  than half the market for made-to-order chips.

Sprawled across several clusters of buildings in  Taiwan, TSMC's most expensive single factory cost  

a reported $17bn, which makes it by some way the  most expensive factory ever built. By comparison,  

Tesla's shiny new gigafactory in  Shanghai cost just a fifth of that.

As a company, TSMC decided long ago it was  quite happy to shun the limelight. Instead,  

the firm labours in relative obscurity making  chips on behalf of the likes of Apple, Huawei,  

and various automobile manufacturers around  the globe. This laser focus, excuse the pun,  

on what TSMC calls 'foundry services'  has enabled it to concentrate entirely  

on breaking new boundaries in the minuscule  scale and peerless sophistication of its chips.

Here's a quick overview of what they actually do.

Intel employee George Moore posited back in 1965  the idea that the number of transistors on any  

given chip would likely double every two years,  as the cost of those transistors halved. Moore's  

Law has held up surprisingly over the following  six decades, thanks in no small part to the work  

of TSMC. Which is why, in turn, computers have  become so much faster and more capable over time.

Moore's Law means transistors are now, in the  second decade of the twenty-first century,  

almost impossibly small. The laptop I'm typing  this on, for instance, rocks a TSMC-made Apple M1  

chip. That chip has over 170 million transistors  crammed onto each square millimeter of silicon,  

with some features just five nanometres  across. A virus is about ten times that  

size. A red blood cell is 1,000 times bigger. Five  nanometres is, get this, fully 100 times shorter  

than the wavelength of visible light. That's  600,000 times smaller than a strand of human hair.

It's really, really titchy, is what we're saying.

But that's just the start. TSMC has  already inked contracts to supply  

chips featuring 3-nanometre architecture.  TSMC has even – in a highly speculative  

process involving semi-metal bismuth  – trialed 1 nanometre chips. Engineers  

call these 'two-dimensional' objects  because that's basically what they are.

But that's all in the future.  Let's look at how TSMC make  

their cutting-edge production chips today.

The heart of the action in  a TSMC factory or the fab,  

short for 'fabrication plant', is the  so-called clean room. TSMC's larger,  

newer fabs have cleanrooms as big as 22 football  fields, or 1600,000 square metres in size.

TSMC cleanrooms are, more precisely, 'level  ten' cleanrooms, which basically means they're  

kept in a state where there's fewer than 10  particles of dust per cubic foot of volume.

As you can imagine, working on  such nanometre scales means even  

the smallest mote of foreign matter could  play havoc with the delicate circuitry.

So workers in the fabs – TSMC employs well over  50,000 people – need to thoroughly scrub up before  

heading to work. That means stashing outside  shoes in a locker, tying their hair up in a net,  

and undergoing a thorough, and  thoroughly futuristic, 'air shower'.

Regular air from the outside world passes  through many layers of filtration systems  

to keep out unhelpful particulates. Assorted other  

environmental disturbances –  fluctuations in temperature,  

swings in humidity, random vibrations, even  magnetic fields are tightly controlled for.

As luck would have it, TSMC's most important  raw material – silicon – happens to be the  

most abundant element found in the earth's crust.  Quartz sand is refined into molten silicon with  

99.9 9 9 9 9 9 9 9 9% purity. For years this  was delivered to the cleanroom in cylinders  

eight inches in diameter, although refinements  to the process, and massive hikes in sales,  

now mean TSMC starts out with 12-inch  hunks of silicon. This means they can fit  

even more onto the same block of raw material,  driving those all-important economies of scale.

This cylinder is sliced into thin wafers. At the  super-fine 3-5 nanometre scales TSMC employees  

work at, precision is a must as even the slightest  mistake would render the cylinder wasted.

The silicon wafers are first treated with  chemicals including arsenic, phosphorus,  

and boron to optimize conductivity  and other useful properties.

These wafers moved to what's known as  the division area, are placed in an  

oven tube where temperature and  gas flows are minutely controlled  

to create an insulating silicon compound  film on the surface of the wafer.

Of course, chips are supposed to conduct  as well as insulate, so the next leg of the  

process – called ion implantation – implants  charged ions into specific pre-chosen regions  

of the silicon wafer. Without getting too  technical, the level of conductivity in the  

final chip is manipulated by finely adjusting  the depth of ion penetration at this stage.

From there the wafers are moved to the  so-called Chemical Vapour Deposition,  

or CVD area of the fab, where a solid-state  reactant – formed from chemical reactions in  

the reaction chamber – is deposited onto  the chip as a thin light-sensitive film.

This is a crucial detail you need to get  your head around – chip architecture is  

nowadays so fine that it's carved out not  using machine tools, but blasts of light.

This special magic takes place in the Photo  Lithography area of the fab. Light is shone  

through a chromium plate etched with the  layout of the chip, as created by designers  

at. In the case of the M1 chip, Apple. The  light that makes it through etches into  

the light-sensitive film, which is what carves  out all those minuscule features and pathways.

The chip designs themselves are obviously  jealously guarded commercial secrets.  

The dense, complex architecture of  each layer – chips typically have  

between 20 and 30 layers packed  together – is transferred from  

computer-aided design systems onto photo  masks also known as plates or reticles.

Once the chip pattern is on the silicon,  the wafer moves to the etching area,  

where fine chemistry is used to  strip away any extraneous silicon.  

It's then polished until it's flat, carefully  inspected, then stacked to make the final chip.

All these parts are ferried around using robots  in the ceiling – 12-inch silicone cylinders is  

too heavy for people – which collectively travel  some 400,000km every day. It's a busy place.

You're probably wondering about that  yellow light the cleanroom is bathed  

in. Remember we said light is what  TSMC used to carve out the chips?  

Well, yellow light has a long electromagnetic  wavelength, and as such doesn't interfere with  

the lithography processes, as shorter wavelengths  like blue might. Indeed, one of the big challenges  

for TSMC going forwards into the brave new  world of 1 nanometre and beyond is the very  

wavelength of light itself. Newer processes use  so-called EUV or 'extreme ultraviolet' lithography  

for reaching the finer details other  chipmakers simply can't compete with.

Oldschool chip maker Intel, for comparison, has  been forced to awkwardly dial back its promised  

five and even seven-nanometre chips plans and  is set to outsource 20% of its manufacturing to  

TSMC over the next few years – an embarrassing  climbdown for such a global household name.

Over the past few months, the central  role of TSMC to the global economy  

has itself been thrown into sharp  focus. Taiwan's geopolitical status,  

in the shadow of the People's Republic Of  China's claims on the territory, make it look  

increasingly vulnerable. Already, recent global  shortages led to car manufacturers like Toyota,  

Ford, and Volkswagen halting production because  they couldn't get hold of TSMC chips fast enough.

TSMC is currently expanding onto the  Chinese mainland in an effort to win  

favor with the People's Republic as well  as opening plants in Europe and the US.  

The better TSMC can get at making and  shipping their wares around the world,  

the more we'll all come to rely  on them when the chips are down.

What do you think? Is it dishonest  for other companies to market the  

work of TSMC factories as their  own? Let us know in the comments,  

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