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)