Hello everyone, welcome to the ZimZimDIY channel. Today, I will explain an electronic device called IGBT. Recently, IGBT has become very popular. I will explain it in my own way, in a simple way, in the style of the ZimZim channel. For IGBT, we will see it as a main component of inverter welding machines, plasma TVs, and electric stoves. So, what is IGBT? IGBT is an electronic device, a type of semiconductor that controls the on-off of electric current with a small voltage. Its full name is Insulated Gate Bipolar Transistor, which combines the advantages of transistors and MOSFETs. The advantage of transistors is that they have a low output impedance. Simply put, they can flow a lot of voltage and are resistant to voltage. The advantage of MOSFETs is that they have a high input impedance. Simply put, they almost do not use any current for biasing, but use a small voltage to stimulate their operation. As a result, their control circuits or drive circuits can be designed more easily. And another advantage is that it can be switched on and off quite quickly. So IGBT is like joining the half-and-half project, combining the advantages of both, which is pulling the C and E legs of the transistor as the output, and pulling the Gate leg of the MOSFET to be the input. When combined, the symbol looks like this. Of course, IGBT has both P-channel and N-channel, but the properties of the P type are inferior. Therefore, P-channel is not very popular. Let's look at the structure of IGBT. Inside, there will be 3 terminals. Terminal 1 is the Gate terminal. Terminal 2 is the Emitter terminal. Note that the Emitter terminal is placed on 2 sides. But both sides are connected to each other, so it is a single terminal. And terminal 3 is the Collector terminal, placed at the bottom. The top surface is coated with silicon dioxide (Sio2), which acts as an insulator. Which will make the Gate leg float. Therefore, there is no part that touches other parts. If you have watched the MOSFET clip, the working principle of the gate leg in this part will be exactly the same. For better understanding Friends can go back and watch it. After that, he will divide it into 2 layers. The lowest layer, he will call it the Injector Layer, which means he will inject substance P into another layer that looks like a 3-way water pipe. This will be the largest area. He will call it the Drift Layer. He will put substance N in. And at this corner, he will put substance P on both sides. And at the last part, which is attached to the Emitter terminal, he will put substance N. For the + sign after N and P here, understand that there is a concentrated doping of substances or the concentration of electrons will be quite high. As for the - sign here, friends should understand that there is a lesser doping of substances or the concentration of electrons is quite low. Understand it like this. In fact, IGBT is similar to a thyristor. For example, SCR has 4 layers of substances and 3 PN Junctions. But SCR, its on-off works quite slowly. Therefore, it is not suitable for high-frequency work. If we consider only half of the figure, it will be clearly seen. In normal conditions, if we connect leg C to the positive terminal and leg E to the negative terminal, the current cannot flow across because it will be stuck at the junction of the edge of P here. If we switch the power supply terminals, it will be even worse. It will be stuck at two junctions. So how do we make it conduct current? That's right. We have to try to make this area as N-type as possible so that the current can flow through. How do we do that? We can do this by having another power supply, which will be a control power supply. We will use the positive terminal to connect to the gate leg. When the gate leg receives a positive voltage, there will be a positive charge coming to this place. And it will create some kind of magnetic field. It attracts electrons in the P-type to stick to it. It will be like creating a small bridge that allows the current to flow. Now, if you look at the figure, the electrons that come in more have changed the P layer here into a temporary N layer. And the more we increase the voltage on the gate leg, the wider this bridge will be. The more current can flow through. When the current flows more, this area may open up to this long. It is possible. This depends on the manufacturer. How do they design their products? If we look at it from the perspective of the electrons that run, it will look like this. And don't forget that there are two sides of the Emitter leg, so it can flow in both directions. When it flows and meets here, it makes the IGBT that we designed flow more current. Therefore, the IGBT can withstand high current. When we combine many advantages, we cannot deny that we will see more of them soon. For IGBT, it is currently under continuous development. Many numbers are now starting to switch higher frequencies. We will have to follow in the future to see