Bench Talk

Have you ever had the urge to boil your iPhone SE in water, torch your iPhone 6 at a temperature of 6,000° F, or bake your iPhone 5S inside of a cake at 350° F?

In case you needed me to tell you, don’t do it.

Over the past five years, a Ukrainian YouTuber by the name of “TechRax” has been doing some outrageous things to his electronic gadgets. Yes, he actually did all of those things I mentioned, and he destroyed a cluster of electronics in the process. If you don’t believe me, he has a plethora of other videos that will make you shake your head in bewilderment.

Image: TechRax: YouTuber TechRax boils an iPhone. (Image Credit: TechRax/YouTube)

In most of his videos, the YouTuber’s phone displays a temperature warning, making it obvious that the phone will no longer work. The same thing would occur if electronic devices were placed in incredibly cold conditions. Even on winter days where temperatures do not drop below –17° C (0° F), it is a bad idea to accidentally leave your laptop in the back seat of your car, as those conditions can affect your battery life and even your display screen. (Plus you could get robbed!)

So why does he expose his electronics to these awful scenarios? I have no idea. But I will tell you why these electronic experiments do not work out for him. Traditional electronics simply are not made to withstand these kinds of extreme temperatures. Conventional electronics are designed to operate at temperatures between –55° C and 125° C. However that is not to say that electronics can’t operate at temperatures outside of this range. This just calls for a set of “extreme” electronics.

For example, low-temperature electronics have been a vital part of space missions, beginning with the Infrared Astronomical Satellite (IRAS) in 1983. The reason was not because of the outer-space environment, but to greatly reduce thermal energy and enable sensors to detect extremely faint infrared waves.

Image: IRAS: The Infrared Astronomical Satellite (Image Credit: JPL/NASA)

Subsequent missions using cold electronics included the Cosmic Background Explorer (COBE) and the Infrared Space Observatory (ISO), to name a few. To give you an idea, the 60-cm diameter ISO telescope was cooled by superfluid liquid helium to temperatures of about –271° C (only 2° C above absolute zero).

In our solar system, as one moves farther away from the sun and beyond Earth’s orbit, temperatures get pretty cold. Not much of our solar system maintains a temperature inside of the “traditional” temperature range, so developing electronic components for temperature extremes is necessary if we want to further space exploration.

Space is not the only application area for these extreme electronics. In geothermal energy and oil production, temperatures can reach over 200° C, causing conventional microelectronics to go beyond their limits, and into the “land of no return,: i.e., permanent failure.

I contacted Dr. Randall Kirschman, who has been consulting on low- and high-temperature electronics for over 30 years, and he shed some light on the high-temperature electronics field. “Historically, the primary use area for high-temp electronics has been ‘well logging,’ which is sending sensors into an oil well bore to measure conditions during exploration or operation. The ‘emerging’ application area is automobile electronics, including combustion engine, hybrid, and electric autos,” said Kirschman.

According to the expert, high-temperature electronics are also being studied for use in space applications, such as exploration of Venus’ surface, which on average runs up to about 460° C. Venus robotic probes and landers would require motors and actuators to perform a load of functions in this environment, such as manipulating robotic arms and drills, and providing traction for surface propulsion—much like what Curiosity is doing on Mars. A group of engineers from Arkansas Power Electronics International, Inc. have been looking at silicon carbide (SiC), a prime semiconductor material to use in these conditions, because it has a theoretical junction temperature limit well over 600° C.

Two years ago, engineers from the Fraunhofer Institute for Microelectronic Circuits and Systems (IMS) in Germany invented a new kind of computer chip capable of withstanding temperatures over 300° C, without performance loss. While the engineers admit that conventional semiconductor chips (CMOS) can sometimes tolerate temperatures of up to 250° C, their performance and reliability fall off rapidly.

Image: Fraunhofer Institute Harsh Environments (Image Credit: Fraunhofer Institute for Microelectronic Circuits and Systems)

So the team came up with a specialized high temperature for a "silicon-on-insulator" CMOS process in which it introduced a layer that insulates the transistors from one another. The insulation reduces leakage currents that occur from operation of the chip. The team also employed tungsten metallization for its chips, which is less temperature-sensitive than the aluminum typically used, increasing the life of the chips.

Aside from space and inner-Earth applications, extreme temperature electronics are important in the aviation and automotive industries. As cars and airplanes evolve, sensors and control electronics can make their way closer to heat sources, requiring electronics within the vehicles to be able to handle that extra heat.

And if you did not pay attention to a word I wrote, just remember to never bake your iPhone.