Semiconductors at University of Tsukuba:Demonstration of operation at 800°C!

Semiconductors at University of Tsukuba:Demonstration of operation at 800°C!

– Proven by electrical property evaluation equipment capable of measuring up to 900°C –

-Used in underground development, steel, space/aviation industry, etc.-

From the article published in PC Watch, we will deliver a summary report.

Hironori Okumura, Assistant Professor, University of Tsukuba

Semiconductor devices at the University of Tsukuba:

A research team led by Assistant Professor Hironori Okumura

has developed a “semiconductor device

that can be used in harsh environments exceeding 800°C.”

Limitations of silicon semiconductors:

Silicon semiconductors malfunction at 300°C.

Therefore,

it cannot be used for underground resource excavation,

space exploration,

engine peripherals, etc.

Semiconductors operating in environments above 300°C require different devices.

Semiconductor operation in high temperature environment:

It is necessary to use a material close to an insulator.

Aluminum nitride (AlN) crystal diode:

There have already been reports of operation in “diodes and transistors using AlN crystals.”

There is also a theory that “AlN elements are superior in high-temperature regimes.

However,

there are limitations on the equipment used to examine electrical characteristics,

and it has been limited to ”500°C or less that can demonstrate device operation”.

Electrical property evaluation equipment that can measure up to 900°C:
In this study,
we used an electrical characterization system that can measure up to 900°C.
Diodes and transistors were fabricated
and evaluated on proprietary AlN specimens with excellent crystal quality.

AlN sample production and evaluation results:
As a result,
they succeeded in “operating the diode at 827°C
and the transistor at 727°C”.
It was also found that the nickel (Ni) electrode can be used
stably even at 827°C for this device.

Using AlN layer on sapphire substrate:

Sapphire is available in large area samples at low cost.

An AlN layer is used on the sapphire substrate.

Heat resistance was achieved with an element with as simple a structure as possible.

Practicality of AlN elements:

AlN elements are also excellent in practical use.

This technology is expected to contribute

to underground development, steel and space/aviation industries.

https://pc.watch.impress.co.jp/docs/news/1513288.html