1
00:00:00,000 --> 00:00:08,140
Processors have come a really long way over the past few decades, but one thing that's remained constant is the fact that they're based on silicon wafers.

2
00:00:09,300 --> 00:00:12,660
But it turns out we don't have to use silicon substrates.

3
00:00:12,660 --> 00:00:20,160
In fact, if we print transistors on another type of material, we could get processors that are not only cheaper, but bendable.

4
00:00:22,100 --> 00:00:29,000
That's right. While everyone is talking about foldable phone screens, scientists have been working on a flexible ARM-based processor

5
00:00:29,240 --> 00:00:35,800
printed on plastic. But how the heck do you put transistors on plastic and why would we want a flexible CPU anyway?

6
00:00:35,800 --> 00:00:41,060
So it turns out that we've actually been putting transistors onto materials other than silicon for a long time now.

7
00:00:41,420 --> 00:00:46,720
Specifically, I'm talking about oxide thin film transistors, better known as TFTs.

8
00:00:47,000 --> 00:00:50,440
These have been used for quite a while in run-of-the-mill LCD screens.

9
00:00:50,480 --> 00:00:57,880
The idea is that instead of silicon, the transistors are printed onto some kind of non-conducting substrate, such as glass.

10
00:00:57,920 --> 00:01:04,920
But even though we've been using this tech for displays for a long time, full-fledged CPUs are a much more complicated ballgame,

11
00:01:04,920 --> 00:01:08,640
kind of like when you get a double reverse triple-out-of-bounder in the 8th inning.

12
00:01:10,320 --> 00:01:17,320
And the bendable CPU we're talking about today is notable because not only is it, well, a full-fledged CPU,

13
00:01:17,440 --> 00:01:24,040
but it uses an existing architecture that's already been put into tons of devices, the ARM Cortex M0.

14
00:01:24,320 --> 00:01:32,400
The new chip is essentially an M0 core, plus a small amount of memory on a plastic substrate, printed using photolithography,

15
00:01:32,600 --> 00:01:39,240
meaning the printing process is similar to how conventional CPUs are made, which you can learn lots more about up in this video.

16
00:01:39,400 --> 00:01:44,200
The transistors themselves can be made from indium-gallium zinc oxide, better known as

17
00:01:44,800 --> 00:01:48,720
IGSO, again commonly used in TFT displays at a low cost.

18
00:01:48,720 --> 00:01:57,560
Of course, since we're talking about cheap production methods, you might think that the plastic ARM, as it's called, isn't very computationally powerful, and...

19
00:01:58,360 --> 00:02:04,600
Well, you'd be right. It runs at only 29 kilohertz and is built on an 800 nanometer process,

20
00:02:04,600 --> 00:02:09,320
which is the same process the original Pentium's from 1993 used. Great year.

21
00:02:09,320 --> 00:02:15,600
And the thing isn't even very power efficient. Despite the fact it uses 21 milliwatts of power, which seems low,

22
00:02:15,600 --> 00:02:19,240
it turns out that 99% of that is lost to waste heat.

23
00:02:19,320 --> 00:02:21,960
So yeah, it's slow and inefficient.

24
00:02:22,440 --> 00:02:28,880
So what's the point? So, remember how we said the Cortex M0 is in a huge number of embedded devices already?

25
00:02:29,040 --> 00:02:34,920
Putting the M0 on flexible plastic means a chip that's complex enough to handle more advanced functions

26
00:02:34,960 --> 00:02:40,680
could go into many more products, especially in cases where silicon is too expensive or too brittle.

27
00:02:40,680 --> 00:02:45,000
Even though the plastic ARM's implementation of the M0 is quite slow, as we said,

28
00:02:45,080 --> 00:02:50,600
it should still be around 12 times as powerful as previous integrated circuits based on plastic.

29
00:02:50,600 --> 00:02:57,240
Plastic ARM would have enough computational muscle to be connected to environmental sensors and alert users to real-time conditions.

30
00:02:57,240 --> 00:03:04,440
Think about a plastic ARM chip inside food packaging that could tell if the food inside was spoiling instead of going by an expiration date.

31
00:03:04,440 --> 00:03:08,520
Or how about a bandage that could keep an eye on how well your cuts are healing?

32
00:03:08,520 --> 00:03:15,880
It's like a little tiny doctor on your finger. Although we do already have microchips that can accomplish some tasks that plastic ARM is envisioned for,

33
00:03:15,880 --> 00:03:21,080
plastic ARM could enable them to be deployed in many more environments for much less money.

34
00:03:21,080 --> 00:03:28,440
But I wouldn't expect to see it in the immediate future, as the plastic ARM prototype that was just developed can only execute a few hard-coded programs.

35
00:03:28,440 --> 00:03:31,720
And scientists still need to make the chip more power efficient.

36
00:03:31,720 --> 00:03:39,000
However, as time goes on, ARM believes we could see chips like these in more than a trillion objects over the course of 10 years.

37
00:03:39,000 --> 00:03:44,040
Hopefully, some of them will end up in lottery tickets, so I can be disappointed as soon as the drawing happens.