How CPUs and Processors are Made for Smartphones, Laptops, and Desktops

hey there my name is gary sims and this is gary explains and i have lots of videos here on this channel dealing with the individual aspects of the processes that we find in our smartphones laptops and desktops however i realize i haven't got a general overview of the whole process from the beginning through the bits and in the middle right through to the end to where we get new processors in our phones so that's what i'm going to look at today an overview of how we get processors cpus gpus how we get them in our phones laptops on desktops so if you want to find out more please let me explain now creating the modern day processes that we find in our smartphones laptops and desktops is a costly and complex business at the best this is just going to be a brief overview of the many many parts that have to come into play to actually get those devices into our hands now i want to look at it in six different parts first of all the idea of fab versus fab less then the look at the idea of a transistor because it is all based on transistors then the process node you know seven nanometers five nanometers and all that kind of stuff then lithography a company called asml a dutch company we'll go into those and finally a look at some of the pricing now hopefully on the way we'll touch enough bases that we kind of get this general overview of what happens to get those processors in our devices so let's start with fab versus fab less now in the past there were companies that kind of did designs of chips and then they kind of made the chips as well and that worked for a few decades however in the last kind of 10 20 years the cost of developing uh chips building chips at the latest bleeding edge technology the price is just going up and up and up and up and up so many companies decided to separate themselves from their manufacturing and from the design and make two different companies and the classic example of that is amd when in 2008 2009 it split off its manufacturing part into a company called global foundries and then it remained just as a design company now a company that just designs chips but uses a third party to build those chips is called fab less a fabulous chip company because it doesn't own a fab now a fab is the name you give to the factory multi-million billion dollar factory where the chips are actually made so a fabulous company just does the design and then it has a contract with another company that just does the manufacturing and we'll look at those uh a bit more in a moment so which are the companies that actually physically make microprocessors today but of course you've got intel so intel designed its own processors the intel i5 the i7 and so on and it manufactures them itself and it's also in the process of opening up its foundry services so they can offer manufacturing uh contracts to outside companies so it's acting as a third-party manufacturer then you've got companies like samsung electronics they also have a fairly sizable manufacturing component you've got global foundries who i mentioned earlier spun off from amd and you've got tsmc and there are some other ones like sm ic and umc that are also around but those are the big players so if you look at that list intel and samsung are the only two companies that can technically design their own processes and then manufacture them other companies have to design them and then they work with a manufacturer to actually physically produce those microprocessors so who are the big fabulous chip designers well amd of course because it spun off its global foundry so it's now a fabulous company apple all of the processes you find in the iphones the ipads the new macs are all designed by apple but they use a third-party tsmc mainly to manufacture those qualcomm nvidia sci-5 when it comes to risk five chips and so on and so on so lots of big names that we hear about the design processes snapdragon processors mediatek for example another one but they all use a third-party samsung mainly tsmc mainly to manufacture those processors just want to bust a quick myth that i read sometimes in the comments and that is if a company like apple for example has a contract with samsung to manufacture its processors does that mean that samsung can copy its designs well no it doesn't and there's a couple of reasons for that first of all of course it can clone the designs because it's already manufacturing and it could manufacture a million of them for apple and then manufacture a million of them for itself but of course what can it do with those chips it's not building iphones and so it can't just take that chip and throw it into one of its own devices and then of course if it did try to do that and it was ever discovered then that would be of course the end of samsung completely and the second reason why it can't happen is that when you get the layout really what you're getting is a layout of transistors we'll talk more about transistors in a minute and these transits these chips have billions of transistors and you can't just look at a map of a billion transistors and say oh i see now how they're doing that really clever thing they're doing in their gpu you just can't do that so there isn't really the way to reverse engineer it and even if there was if it was ever found out then of course it would destroy the business it's not worth it because what they want is to continue and generally these businesses work kind of in a way with a firewall what they mean by that is that the people over who are developing the next samsung galaxy device don't have access to what's going on in the kind of the manufacturing branch of the company to make sure there's no leakage of information now this whole industry in general is called the semiconductor industry but what is a semiconductor so a semiconductor is a material that can conduct current but only partly so it's not an insulator let's say say like rubber or something and neither is it a conductor like copper it's it's somewhere in between and silicon is a good example of a semiconductor something that in some circumstances can act as an insulator and the some circumstances can act as a conductor now pure silicon crystals on their own have no free electrons they bind together in a lattice where there are no free electrons which means that current flow doesn't happen which is why it then acts as an insulator however you can do some things to silicon to turn it into a conductor and to do this you add other elements into the uh lattice structure into the crystal structure and that's called doping now if you put in elements that have more electrons than silicon for example phosphorus then you create an n-type conductor because there are more electrons than are needed for the lattice and so there are free electrons which are able to conduct the current if you put in a different type of material let's say boron which only has three electrons which means then you have a p-type conductor and in this case what happens there are now three holes which electrons will flow to and jump in and so the two of these things together are actually the foundation of a transistor so if the n-type conductor has an excess of electrons and the p-type conductor has a lack of electrons if you sandwich them together and you may have heard this term npn or pnp that's two different types of transistor then you create this sand wedge which normally doesn't actually allow current to flow and there are lots of technical reasons about this about the pn junction and the barriers that are created but basically if you apply an a current to that middle layer of that sandwich something happens with the electrons that bridges the gap between them and allows the electrons to flow very much like a switch so a transistor is this grouping together of this n-type conductor with the excessive electrons and the p-type conductor with not enough electrons and you put them together in this sandwich and there's two legs for the input and the output to allow the positive and the negative to connect together and there's one in the middle and when you apply a current to that one in the middle this thing happens with the electrons due to this nature of the p and the end it builds a bridge between them and then current is allowed to flow so now you have an automatic way of allowing current to flow or stopping current switch and then of course if you combine those together you can start to build up circuits and they're fully automated because the only thing you need to activate the switch is an electrical current that goes to that middle part of the transistor now using transistors you can then start to build up things called logic gates now when we're dealing with building circuits logic circuit processors cpus we start with these very fundamental building blocks called gates an and gate an or gate a not gate and so on and so on and you can build those up using transistors so here is the symbol for a transistor and as you can see you see the three pins the three legs on it and the idea being if you look at classic current representation so that's flowing from uh the positive to the negative then the arrow there shows the flow and you come down the positive and then on to ground but it only works when there is a current applied to that middle pin if you look at the actual picture of a transistor kind of a model of it for an actual macro processor you can see that here we're dealing with electron flow so we're going from negative through to positive and what happens you've got the p and the n types of material there when there is a current on the middle pin that allows the electrons to flow from one side to the other due to this difference in the p and the n materials let's look at the logic of an and gate an and gate if i've got the down there at the bottom if level is equal to 10 and live is equal to one so we want both things to be true if it's level 10 and they've only got one life then we want to do something uh in our game let's say that we're writing here so uh the truth table as they call it for an and gate is this when there's zero and a zero you also want a zero so if neither of them are true then the final thing is not true if one of them is true either zero one or one zero then still the whole thing isn't true because it's not level ten analyzer it might be just level ten and lives two or it might be lives one and level 27 but only when they're both true so one one then you want to get a one and if you look here here's an example of how you'd build that using two transistors so the current is flowing from the top vcc all the way down to the ground now if you've got a current if there's a one on the transistor at the top but there's a zero let's say of a transition at the bottom we're looking at truth table one and zero one or zero of course you get a zero because the second switch is not activated so the output is zero but if there's a one and a one then of course both transistors are now switched on both switches are activated and so you get this flow out to the output which will be positive now that really is one of the most simplest logic gates that you can build and from logic gates after that you then get a whole bunch of other things until you get to the point as i said there are 11.8 billion transistors in the apple a14 so these two transistors here are nothing in comparison to what's going on and the whole thing something that can run a programmer effectively at the end of the day you've got mac os or ios running on a very sophisticated smartphone or laptop all because of these 11.8 billion transistors are all doing their thing in the right sequence so that things have happened on the screen you can move the mouse you can read the keyboard you can write to the hard disk and all those things that happen so the next thing to talk about is the process node and you may have heard of that because it's talked about in nanometers this chip is manufactured using five nanometers or seven nanometers or 10 nanometers and so on what does all that mean well way back in the day when we were talking about these transistors they actually had some physical properties that were related to this nanometer setting so there was for example the gate pitch now for our intensive purposes we can talk about the width and the length it's an oversimplification but it's good enough for us now if you could measure that width and that length you can measure the gaps between them and so on you can come up with this number to say this is a 90 nanometer production run however over the years that number has kind of lost its technical meaning as the design of transistors of change as they come up with different ways of building the transistors it doesn't really make much sense in terms of the physical properties of it however as a marketing scheme every time they were able to double the number of transistors in a process node they just went to the next level in that nanometer range now you might say hold on a second how come we went from 90 nanometers to 65 nanometers why isn't it directly to 45 nanometers well the reason is is if you're dealing with 2d so length and width if you want to double the density you only need to change the width by 0.7 and the length by 0.7 because roughly 0.7 times 9.7 is 0.5 so actually each of those process nodes is 0.7 of the one before it and you can see that most clearly when we went from 10 nanometer two not five nanometer no we went from 10 nanometer to seven nanometer and that's the reason why because it's the 2d part of it because you're dealing with area how many transistors can you get in a certain area so since the physical link between the transistor size and the process name has basically disappeared the whole nanometer thing sometimes is more of a marketing bump than it actually is about the technology also what makes things worse is that some companies use different formulas to calculate the density than others here's a very quick look at the densities that are currently on offer let's start up at the 16 and 14 nanometer range tsmc we're offering 28.2 million transistors per square millimeter samsung were offering 32.5 for their 14 nanometer processor slightly better uh also in name and actually in density and what's interesting is the intel's 14 nanometer was actually 37.5 so it was already better than the offerings from tsmc and samsung then when we get to 10 nanometers tsmc 60.3 samsung 51.8 and intel actually 100 so intel doing much better than tsmc and here it's worth pointing out that some of intel's problems about it being stuck on the older process nodes is actually to do with the marketing because obviously if you see here this is built on seven nanometers this is built on 14 nanometers you instantly think that well the seven nanometer one is better but in some cases actually the technology might be better in an older node from a different company intel really missed a step they're not only in the technology but also in their marketing and if we go down to look at seven nanometers we've got uh 96.4 95.3 tsmc and samsung intel haven't yet got their seven nanometer they're saying when they do have it will be 200 so much much greater than what you get from tsmc and samsung and in fact tsm samsung are getting close to that with their five nanometers 173 million transistors per square millimeter from tsmc less for samsung 127 and in fact i have read a report that's saying maybe intel are considering renaming their seven nanometer as actually five nanometer to make up for this gap in the marketing so earlier on we talked about silicon as in fact it's a semiconductor and it can be doped with other elements like boron and so on so the starting of the manufacturing process is a big lump of silicon that's made from a kind of a quartz of silicon that heated up into a molten and then it's kind of drawn out just like you draw out you know a metal or a glass from these molten liquids that's allowed to cool and then it's cut very thinly into wafers which are then polished so the key to making a microprocessor is a process called lithography so basically using light to help burn on or etch on different layers of the microprocessor because what you want is layers of end material layers of pee material interconnecting wires and you want to build these up layer by layer and you can put photo sensitive a layer on you can expose it to the light shining it through a thing called the mask and the mask is basically the blueprint of those transistors that you're trying to make you can then etch away the bits you don't want using kind of an acid then you might put down another layer and then more lithography and then more etching in fact maybe 60 or 70 layers are built up to actually make all those tiny tiny transistors in fact the whole process from the silicon wafer right through to a chip that you can have kind of with the little legs on it could be over 700 individual steps and processes that need to go through and it can take months to actually get a chip from the beginning through to the end so i said this thing called the mask is used in in conjunction with the photosensitive chemicals that are put on top of the silicon and then when you want to create an n layer or a p layer use an ion implanter that's actually able to introduce the boron or the phosphorus or whatever other materials they're introducing to create that correct conductive layer at that layer of the transistor which in itself is one of 60 or 70 layers and of course as you get smaller and smaller then you need to use shorter and shorter wavelengths for the lithography stage closely a wavelength has its own measurement and today we've arrived at the stage of extreme ultraviolet now extreme ultraviolet is such short wavelengths that even air itself will disperse it so it needs to happen inside of a vacuum now it turns out there's only one company in the world that can make the extreme ultraviolet lithography machines that are needed as part of the process of making the microprocessor and that's a dutch company called asml it is the soul maker of uh extreme ultraviolet lithography machines and they are used by tsmc by samsung by intel and so on and one machine costs around 130 million dollars if you're thinking of buying one then you better have deep pockets and they are so complicated that asml are only able to deliver a few machines every year 31 machines in 2020 that's up from 26 machines in 2019 maybe they're thinking up to 40 machines in 2021 this isn't like manufacturing cars they don't churn out thousands of them at a time they're these machines are complicated slow to build and of course highly highly accurate and how do they make that extreme ultraviolet light well it's not done using a laser that was what was used previously at bigger process nodes now what they need to do is they need to hit tin with a laser 50 000 times a second to create a plasma that plasma itself burns hotter than the surface of the sun and a byproduct of that plasma is itself extreme ultra violet light and some of that manages to find its way through all the mirrors and lenses and actually gets shone onto that bit of the silicon to do that mask with the sensitive material to start to make that microprocessor it's amazing stuff okay so the final thing to look at is cost now on the one hand we've got silicon in these kind of big blocks that get created and that's fairly cheap it's sand one of the most abundant elements on the earth at the other end you get microprocessors that are sold for hundreds of dollars even more so in a desktop in a laptop it is a significant part of the price however we're still able to buy smartphones for only a few hundred dollars thousand dollars even for the latest and greatest so how do you go from silicon to something that's worth several hundred dollars that's of course because the manufacturing process is so complicated millions of dollars just to buy the lithography machines millions and millions of dollars to do the rest of all the automation that needs to happen an entire fab itself can cost billions of dollars so there's a huge investment in just actually getting the factory itself the fab itself up and running then of course the fab once it has more customers it can actually start to recuperate those costs now one of the big things about making any particular chip any one generation of a chip is the mask because that's used inside of that lithography process extreme ultraviolet light and they themselves can cost millions and millions of dollars to create the mask it's very hard to find out how much they actually cost people don't talk about it but i have heard in whispered conversations sometimes even up to a hundred million dollars then once you've got your mask done then of course you can start churning out in a mass production kind of way just think about how many galaxy s21s are sold or how many iphones are sold they need millions and millions of these chips and that is easier because once you have the mask you're kind of just creating again another one and another one and another one so the estimated cost that i've seen knocking around that was for a 16 or 14 nanometer wafer that's 12 inch wafer with obviously hundreds of little chips on it could be 4 000 this goes up to maybe just under six thousand dollars for seven nanometers i've seen it quoted as high as sixteen thousand dollars for a five nanometer but all in all of course you're talking now about mass production millions of these chips that are being sold so that does help however when you consider the mask when you consider the other things you have to pay gartner recommend it cost 271 million dollars to design a seven nanometer chip compared to only 80 million dollars to design a 16 or 14 nanometer chip and 30 million dollars to design a 28 nanometer chip of course these million dollar prices we're talking about do have a relevancy when it comes to things like risk five i've read so many people talking about how they're expecting hardware costs to come down and there's going to be a revolution in open hardware because of risk five and i say no it's the opposite the prices are going up it costs millions and millions or even if you want 28 nanometers you've got to fork out 30 million dollars just to get your chip run going that's not the same as a software revolution like we had with linux where just i can buy a compiler and an internet connection and you are up and running so really don't think about a hardware as a cheap thing it's a very expensive thing it's mass production that allows it to come down to smaller unit prices so they can make their way into smartphones laptops and desktops okay that's about it now obviously a lot was covered there lots and lots of stages lots of things were just skirted over as quick as i can but hopefully you get an idea now from the idea of a transistor how the electrons flow from the p and the n type materials it becomes an automated switch use those switch to make logic gates logic gates combine together even billions of them can make a general purpose cpu you can make gpus with it you can make machine learning accelerators you can make uh dsps you can make all these different types of chips they then get using lithography they get transplanted onto the silicon layers upon layers that are put on and then etched off according to the design to build up these layers of the the silicon chip and then ultimately you get this processor that you have in your smartphone an incredibly complicated process however as i said mass production allows the prices to be reasonable uh so that we can have them in all the gadgets that we have around us okay that's it my name is gary sims this is gary explains i really hope you enjoyed this video are you following me on twitter at gary explains always a good place to check on what else i am talking about over there also what about my newsletter gary explains.com go over there type in your email address no spam just my newsletter i hope you find it interesting okay that's it i'll see in the next one [Music] you

Channel: Gary Explains

Views: 155,836

Keywords: Gary Explains, Tech, Explanation, Tutorial, chip, silicon ingot, EUV, EVU, chips, CPUS, Intel, Samsung, TSMC, Fab, silicon, processor, ASML, transistor, fabless, fab vs fabless, How a CPU is made, Chip Manufacturing, How are Microchips made?, From Sand to Silicon, how transistor works, how transistors work, what is a transistor, npn transistor, semiconductor, transistors, p-type, transistor as a switch, pnp transistor, npn, transistor basics, how does a transistor work

Id: hLwGtucsTms

Length: 25min 4sec (1504 seconds)

Published: Tue Jul 13 2021

Reddit Comments

[u/longoon]

He keeps saying that you apply current to the middle pin of a transistor. I thought you applied voltage to the middle pin?

A transistor base switches the transistor when a certain voltage threshold is reached, not when a certain current is reached?

[u/gecker]

Didn't know about nm stamps being vanity labels and not equating to true transistor density