By now, you’ve probably heard of the “Great Chip Shortage,” and if you’re like many people, you just took it at face value.
But, what exactly is a semiconductor? What do these “chips” do? What does this mean to the automotive world?
The good news is that you don’t have to be a rocket scientist or technological pioneer to understand what semiconductors do. It might be helpful to have passed high school science, but we’re all on board with what a Hail Mary senior year was for all of us, so that’s not a pre-requisite.
Let’s check out the wild world of electric current, charges, diodes, and semiconductors!
Seriously, What’s a Semiconductor?
As the name suggests, a semiconductor is able to conduct electricity, but only partially. It’s not a full-on conductor like copper, but it’s also not an insulator like ceramic. Silicon crystals are one of the most popular types of semiconductor, followed by germanium. All of these are naturally-occurring elements. They have a place on the periodic table of elements and everything. Gallium arsenide is also a semiconductor, but technically is a compound, not one of the pure elements.
The atom pattern of semiconductors is known as a “crystal structure,” because of the neat and tidy way the atoms align. Electrons exist within the atoms, cozied up into layers known as “shells.” The outermost shell is called the valence shell. Valence electrons attract other atoms that happen to be nearby, forming covalent bonds. The crystal structure is caused by valence shells bonding to other valence shells, which happens when all neighboring atoms are the same. Silicon atoms, for example, bond via four electrons in the valence shell.
Technically speaking, crystals aren’t that electronically helpful, but they are easily manipulated. In fact, experts can control what a semiconductor actually does via a process called “doping.” Basically, doping involves changing the crystal structure by introducing impurities. This results in electrical conductivity, because the change in structure allows electrons to move freely.
Are There Different Types of Semiconductors?
While we’re not exactly qualified to run a master class on quantum physics, there are two main types of semiconductors, which means this is a fair and relatively easy question to answer.
P-type semiconductors are created by doping with a material that has fewer electrons than the semiconductor material. Using the example of silicon, boron can be doped into a crystal to create a hole. Boron only has three electrons to silicon’s four electrons. This hole then acts like a positive charge, pulling electrons towards it.
An N-type semiconductor does the exact opposite. In this instance, an element with an extra electron is added. In the case of silicon atoms, phosphorus is a popular dopant. Phosphorus has five electrons, and the spare that cannot bond with a silicon electron is free to move about. This free electron acts like a negative charge, pushing from the other electrons that are bonded.
The interface between these two types of doped semiconductors is known as a p-n junction. These p-n junctions can be specifically created to control the flow of electrons. In turn, this dictates current flows, and basically tells diodes, transistors, and other electronic devices how to behave.
Is There a Simpler Version of This?
Unfortunately, semiconductor technology isn’t really something you can cook up in your basement workshop on the weekends. Unless you’re a physicist, and then by all means, carry on.
Think of semiconductors as the Red Light/Green Light Team Captain at the electron level, if that helps. Diodes say “go that way only.” Transistors can be used as amplifiers to a small electronic signal, or switches, directing traffic between bigger electrical currents. They can also be used as rectifiers, turning the current off.
When you think about it, all of your electronic devices work because someone figured out what crystals to line up in which direction with which added impurity. Semiconductor devices have gained popularity, because they’re very reliable and space efficient.
There’s just one major thing: You need to have a reliable source of pure silicon to create them.
Which Brings Us to the Great Semiconductor Shortage
First, there was COVID-19, which messed up a lot of things, but most significantly for this article, delayed semiconductor chip production and shipping around the world.
Then there was the massive and unusual winter storm in Texas. No, the snow didn’t ruin the semiconductors, but there are three major semiconductor companies in the state: Samsung, NXP, and Infineon. They were shut down due to the weather, which meant no production.
Simultaneously, the Renesas semiconductor factory in Japan caught fire, with much of the equipment being destroyed.
The world’s largest semiconductor company is Taiwan Semiconductor Manufacturing Company (TSMC), which is definitely feeling the crunch of the shortage, with clients such as iPhone and the Amazon cloud to service. But, even TSMC is off track, due to a massive and unusual drought.
With production so far off track, both China and the United States are racing to boost their semiconductor production to meet demand. China has threatened to invade Taiwan to gain control of the global semiconductor market, and TSMC is looking to open a plant in Arizona in order to resume higher production levels.
To make matters even messier, bear in mind that a semiconductor isn’t created by locally sourced artisanal elements. You don’t just pop out to a farmer’s market to grab some silicon and boron. Instead, the design may come from one location, the silicon from another country, equipment, chemicals, packaging, manufacturing… essentially every semiconductor is a global effort, and when multiple cogs in a machine stop working simultaneously, well, any gearhead can tell you that’s when you have Big Trouble.
Right now, that means that electronics production has been slowed or halted. Ford, Ram, and Tesla are all feeling the squeeze, with delays and shift cuts happening around the country. Could the vehicles be built without semiconductors? Short answer: Yes, but don’t you enjoy turning on your windshield wipers when it’s raining? Semiconductors are literally incorporated in every electrical component of your vehicle. Unless you took driving lessons from Barney Rubble, this is going to be problematic.
The good news is that the global leaders are aware of and working on this issue, but as you can imagine, it’s not a simple issue to fix.
So, if you could get that basement workshop up and running so you can start doping some silicon and making semiconductors, that would be just peachy. Just don’t ask us where to get a gallon a gallium arsenide.