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Semiconductors Semiconductors

Maurizio Di Paolo Emilio (00:00): Okay, so more non-ideal factors on top of that. So this to become mature enough to be accepted in the Anup Bhalla (05:50): So people don’t really

thank you, Anup, for this interview. is the reason why people do it because now market. So even though people are working on need fast switching. What they can benefit from
you can make high voltage devices which are ultra wide band gap, they’re working on gallium is that a silicon Silicon carbide FET will have no
Anup Bhalla (00:07): You’re welcome. unipolar. So unlike IGBTs, you’ll get the low on oxide, diamond, aluminum nitride, all kinds of knee-voltage compared to an IGBT. So if you can
state drop, youou won’t have a knee voltage, and things are showing some promise. Even vertical then make the RDS on itself very low, you can get
Maurizio Di Paolo Emilio (00:07): As you you also won’t have any stored charge, so you GaN is showing some promise. But these things lower conduction loss than an IGBT. Now it might
know, I am Maurizio, Editor of Power Electronics can now think about switching a lot faster. So will take a long time to mature. So I think even cost more in today’s world because the volumes
News. And before to go ahead, I would like to that’s the whole reason why people have gone if they are coming, we are looking at another are not there yet, but the fact that it has no knee
know about you. Please introduce yourself. What afterGaN-on-silicon, but they’ve evolved very decade before they are good enough and cheap voltage [MDPE1] and very, very low conduction
do you do at the United Silicon Carbide? differently. enough to compete with silicon carbide. The losses, well then you can use this to increase the

silicon carbide now, the volume is picking up range of your car, increase efficiency.
Anup Bhalla (00:21): Hi, my name is Anup Anup Bhalla (02:21): Silicon carbide is a rapidly, costs are dropping rapidly because of
Bhalla and I’m the VP of Engineering for United lot older and everybody makes vertical devices volume and technology advance, so it’s becoming Anup Bhalla (06:20): My favorite thing is
Silicon Carbide. I’ve been working there since because you can make oxides on silicon harder and harder to compete with. And soon you keep the temperature low because you
2012. But before that, my whole career was in carbide. Our company is of course, using the it will be, in a few years time, it will be an eight use this higher, lower conduction loss and
Silicon. So, I’ve been in wide-bandgap since 2012. JFET structure, which has better mobility in inch. So it’s a hard job for a new semiconductor higher… Reduce power losses to keep all the
the channel area. GaN has gone a different way. to come in and replace silicon carbide. That’s my temperatures low. This actually improves

Maurizio Di Paolo Emilio (00:37): Nice, They have gone and decided to use an RF like view. reliability. And even when you accelerate the car,
good. So I would like to know, to go in deep structure, which is called a hemt. It’s a lateral you can design your semiconductor so the peak
about wide-bandgap semiconductor, as device. And because you can make different Maurizio Di Paolo Emilio (04:29): Yeah, so power losses remain low under all conditions.
you know. So wide-bandgap semiconductor semiconductors with good crystal matching, silicone carbide semiconductor switches have But this is a good benefit for these ultra low
technology, such as silicone carbide, SIC, S-I-C, GaN and AlGAN on top of it, you can form a 2D many features as you know that make them RDS on devices. And there’s another area where
and gallium nitride offer benefits in a good range electron gas, and this is another interesting way serious contenders to replace, as you mentioned, I think this may become important in the future.
applications from universal wireless charging to to make a power device. IGBT in electrical vehicle inverter applications. The I think our ultra low RDS on devices can be used
power converters. So tell me why GaN and silicon latest generation of silicon carbide devices offer, to replace DC contactors inside the car. There’s
carbide and for which markets we can find a lot Anup Bhalla (02:56): So these are both as you know because you wrote a lot of articles, many of them in the car everywhere. If you

of application. And do you think that there is playing a solid role in the market, especially ultra-low on resistance. What is the role of a replace the DC contactor with these low RDS
another material that could be a good competitor around where high-frequency power conversion silicone carbide in automotive, for example, just to on devices, instead of just doing the contactor
for gallium nitride and silicon carbide? is required. So these will compete, GaN, Silicon be in for particular market? And in particular, the function, now you can do more safety functions
Carbide compete in part supplies. But when it purpose of on resistance, SIC fets with the vertical like current limiting. So there’s many, many, many
Anup Bhalla (01:23): Sure. So, the basic thing comes to replacing IGBTs and inverters, I think trench of a very low on resistance. uses for these low RDS on devices.
about wide band gap semiconductors is that silicon carbide has a better shot simply because
because of that crystal structure, it has a very of power density. It is much better with the Anup Bhalla (05:26): Yeah, this is a great Maurizio Di Paolo Emilio (07:14): So a

high critical field before breakdown happens. So vertical device to do these high current, high question. So people already understand that new designs in whole power conversion areas,
this means if you’re building a semiconductor power modules and solutions. there is a role for silicon carbide in the onboard including high power, a AC/DC and DC/DC
device, the voltage supporting region that you chargers and DC/DC converters, but when you converters, which are using SIC FETs. SIC silicon
build, it can be usually 10 times thinner than Anup Bhalla (03:24): It can also use a lot of come to the traction inverters, many people don’t carbide technology could not exploded without
silicon, if you use GaN or silicon carbide. And you the packaging technology that was developed for need fast switching. You may need to maintain the use of so low inductance packaging. So
can put 10 times more electrons in there. You’re IGBTs because it’s simpler for them. So this is a low dV/dT so that you don’t affect the motor about the packaging, what is the rule of it in
10 times higher doping. So essentially, you can what’s happening. And it’s taken almost 20 years windings, for example, if the… silicon carbide? And so which are the features to
roughly get a hundred times lower resistance or more for Silicon carbide to become mature consider for it?
for making the same device. But there are many enough, maybe almost 30 now, for Silicon carbide Maurizio Di Paolo Emilio (05:49): No.

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