The incredible chemistry powering your smartphone | Cathy Mulzer

Translator: Ivana Korom Reviewer: Joanna Pietrulewicz

When I waltzed off to high school with my new Nokia phone,

I thought I just had the new, coolest replacement

for my old pink princess walkie-talkie.

Except now, my friends and I could text or talk to each other

wherever we were,

instead of pretending,

when we were running around each other's backyards.

Now, I'll be honest.

Back then, I didn't think a lot about how these devices were made.

They tended to show up on Christmas morning,

so maybe they were made by the elves in Santa's workshop.

Let me ask you a question.

Who do you think the real elves that make these devices are?

If I ask a lot of the people I know,

they would say it's the hoodie-wearing software engineers in Silicon Valley,

hacking away at code.

But a lot has to happen to these devices

before they're ready for any kind of code.

These devices start at the atomic level.

So if you ask me,

the real elves are the chemists.

That's right, I said the chemists.

Chemistry is the hero of electronic communications.

And my goal today is to convince you

to agree with me.

OK, let's start simple,

and take a look inside these insanely addictive devices.

Because without chemistry,

what is an information superhighway that we love,

would just be a really expensive, shiny paperweight.

Chemistry enables all of these layers.

Let's start at the display.

How do you think we get those bright, vivid colors

that we love so much?

Well, I'll tell you.

There's organic polymers embedded within the display,

that can take electricity and turn it into the blue, red and green

that we enjoy in our pictures.

What if we move down to the battery?

Now there's some intense research.

How do we take the chemical principles of traditional batteries

and pair it with new, high surface area electrodes,

so we can pack more charge in a smaller footprint of space,

so that we could power our devices all day long,

while we're taking selfies,

without having to recharge our batteries

or sit tethered to an electrical outlet?

What if we go to the adhesives that bind it all together,

so that it could withstand our frequent usage?

After all, as a millennial,

I have to take my phone out at least 200 times a day to check it,

and in the process, drop it two to three times.

But what are the real brains of these devices?

What makes them work the way that we love them so much?

Well that all has to do with electrical components and circuitry

that are tethered to a printed circuit board.

Or maybe you prefer a biological metaphor --

the motherboard, you might have heard of that.

Now, the printed circuit board doesn't really get talked about a lot.

And I'll be honest, I don't know why that is.

Maybe it's because it's the least sexy layer

and it's hidden beneath all of those other sleek-looking layers.

But it's time to finally give this Clark Kent layer

the Superman-worthy praise it deserves.

And so I ask you a question.

What do you think a printed circuit board is?

Well, consider a metaphor.

Think about the city that you live in.

You have all these points of interest that you want to get to:

your home, your work, restaurants,

a couple of Starbucks on every block.

And so we build roads that connect them all together.

That's what a printed circuit board is.

Except, instead of having things like restaurants,

we have transistors on chips,

capacitors, resistors,

all of these electrical components

that need to find a way to talk to each other.

And so what are our roads?

Well, we build tiny copper wires.

So the next question is,

how do we make these tiny copper wires?

They're really small.

Could it be that we go to the hardware store,

pick up a spool of copper wire,

get some wire cutters, a little clip-clip,

saw it all up and then, bam -- we have our printed circuit board?

No way.

These wires are way too small for that.

And so we have to rely on our friend: chemistry.

Now, the chemical process to make these tiny copper wires

is seemingly simple.

We start with a solution

of positively charged copper spheres.

We then add to it an insulating printed circuit board.

And we feed those positively charged spheres

negatively charged electrons

by adding formaldehyde to the mix.

So you might remember formaldehyde.

Really distinct odor,

used to preserve frogs in biology class.

Well it turns out it can do a lot more than just that.

And it's a really key component

to making these tiny copper wires.

You see, the electrons on formaldehyde have a drive.

They want to jump over to those positively charged copper spheres.

And that's all because of a process known as redox chemistry.

And when that happens,

we can take these positively charged copper spheres

and turn them into bright,

shiny, metallic and conductive copper.

And once we have conductive copper,

now we're cooking with gas.

And we can get all of those electrical components

to talk to each other.

So thank you once again to chemistry.

And let's take a thought

and think about how far we've come with chemistry.

Clearly, in electronic communications,

size matters.

So let's think about how we can shrink down our devices,

so that we can go from our 1990s Zack Morris cell phone

to something a little bit more sleek,

like the phones of today that can fit in our pockets.

Although, let's be real here:

absolutely nothing can fit into ladies' pants pockets,

if you can find a pair of pants that has pockets.

(Laughter)

And I don't think chemistry can help us with that problem.

But more important than shrinking the actual device,

how do we shrink the circuitry inside of it,

and shrink it by 100 times,

so that we can take the circuitry from the micron scale

all the way down to the nanometer scale?

Because, let's face it,

right now we all want more powerful and faster phones.

Well, more power and faster requires more circuitry.

So how do we do this?

It's not like we have some magic electromagnetic shrink ray,

like professor Wayne Szalinski used in "Honey, I Shrunk the Kids"

to shrink his children.

On accident, of course.

Or do we?

Well, actually, in the field,

there's a process that's pretty similar to that.

And it's name is photolithography.

In photolithography, we take electromagnetic radiation,

or what we tend to call light,

and we use it to shrink down some of that circuitry,

so that we could cram more of it into a really small space.

Now, how does this work?

Well, we start with a substrate

that has a light-sensitive film on it.

We then cover it with a mask that has a pattern on top of it

of fine lines and features

that are going to make the phone work the way that we want it to.

We then expose a bright light and shine it through this mask,

which creates a shadow of that pattern on the surface.

Now, anywhere that the light can get through the mask,

it's going to cause a chemical reaction to occur.

And that's going to burn the image of that pattern into the substrate.

So the question you're probably asking is,

how do we go from a burned image

to clean fine lines and features?

And for that, we have to use a chemical solution

called the developer.

Now the developer is special.

What it can do is take all of the nonexposed areas

and remove them selectively,

leaving behind clean fine lines and features,

and making our miniaturized devices work.

So, we've used chemistry now to build up our devices,

and we've used it to shrink down our devices.

So I've probably convinced you that chemistry is the true hero,

and we could wrap it up there.

(Applause)

Hold on, we're not done.

Not so fast.

Because we're all human.

And as a human, I always want more.

And so now I want to think about how to use chemistry

to extract more out of a device.

Right now, we're being told that we want something called 5G,

or the promised fifth generation of wireless.

Now, you might have heard of 5G

in commercials that are starting to appear.

Or maybe some of you even experienced it

in the 2018 winter Olympics.

What I'm most excited about for 5G

is that, when I'm late, running out of the house to catch a plane,

I can download movies onto my device in 40 seconds

as opposed to 40 minutes.

But once true 5G is here,

it's going to be a lot more than how many movies

we can put on our device.

So the question is, why is true 5G not here?

And I'll let you in on a little secret.

It's pretty easy to answer.

It's just plain hard to do.

You see, if you use those traditional materials and copper

to build 5G devices,

the signal can't make it to its final destination.

Traditionally, we use really rough insulating layers

to support copper wires.

Think about Velcro fasteners.

It's the roughness of the two pieces that make them stick together.

That's pretty important if you want to have a device

that's going to last longer

than it takes you to rip it out of the box

and start installing all of your apps on it.

But this roughness causes a problem.

You see, at the high speeds for 5G

the signal has to travel close to that roughness.

And it makes it get lost before it reaches its final destination.

Think about a mountain range.

And you have a complex system of roads that goes up and over it,

and you're trying to get to the other side.

Don't you agree with me

that it would probably take a really long time,

and you would probably get lost,

if you had to go up and down all of the mountains,

as opposed to if you just drilled a flat tunnel

that could go straight on through?

Well it's the same thing in our 5G devices.

If we could remove this roughness,

then we can send the 5G signal

straight on through uninterrupted.

Sounds pretty good, right?

But hold on.

Didn't I just tell you that we needed that roughness

to keep the device together?

And if we remove it, we're in a situation where now the copper

isn't going to stick to that underlying substrate.

Think about building a house of Lego blocks,

with all of the nooks and crannies that latch together,

as opposed to smooth building blocks.

Which of the two is going to have more structural integrity

when the two-year-old comes ripping through the living room,

trying to play Godzilla and knock everything down?

But what if we put glue on those smooth blocks?

And that's what the industry is waiting for.

They're waiting for the chemists to design new, smooth surfaces

with increased inherent adhesion

for some of those copper wires.

And when we solve this problem,

and we will solve the problem,

and we'll work with physicists and engineers

to solve all of the challenges of 5G,

well then the number of applications is going to skyrocket.

So yeah, we'll have things like self-driving cars,

because now our data networks can handle the speeds

and the amount of information required to make that work.

But let's start to use imagination.

I can imagine going into a restaurant with a friend that has a peanut allergy,

taking out my phone,

waving it over the food

and having the food tell us

a really important answer to a question --

deadly or safe to consume?

Or maybe our devices will get so good

at processing information about us,

that they'll become like our personal trainers.

And they'll know the most efficient way for us to burn calories.

I know come November,

when I'm trying to burn off some of these pregnancy pounds,

I would love a device that could tell me how to do that.

I really don't know another way of saying it,

except chemistry is just cool.

And it enables all of these electronic devices.

So the next time you send a text or take a selfie,

think about all those atoms that are hard at work

and the innovation that came before them.

Who knows,

maybe even some of you listening to this talk,

perhaps even on your mobile device,

will decide that you too want to play sidekick

to Captain Chemistry,

the true hero of electronic devices.

Thank you for your attention,

and thank you chemistry.

(Applause)