Monday, December 27, 2010

Gallium Nitride (GaN) for blue LEDs?

Do you know how Gallium Nitride (GaN) plays a big role in blue LED lightings?

Gallium Nitrid (GaN) is not only used for blue LED, but, as SiC, it is widely used for next generation wide band gap semiconductor devices.

Unlike Si or SiC, it cannot be created as a wafer.
Instead it is epitaxial grown, as a thin film, on a Si or Sapphire substrate.
Therefore, if you want to evaluate the thermal conductivity of GaN, you must evaluate as thin film.

Engineers are researching high purity GaN crystals these days also.
But it could be created in a small amount only.

Thermal Microscope (TM) could evaluate GaN in either forms.

We cannot share the actual results from our clients in details, but as we measured GaN, the values were very similar to the literature values.

TM could evaluate the samples with high spatial resolutions.
It could also evaluate the thin film samples as well.

If you are interested, please take a look at Thermal Microscope (TM).

Wednesday, December 15, 2010

SEM and Sputtering Service

Bethel is offering services with SEM and sputtering.

We have a Keyence SEM.
The price is 15,000JPY for 2 photographs for single sample.
+5,000JPY per extra photos.

Sputtering: Molybdenum(Mo)
The price if 15,000JPY for one batch.
7,500JPY/batch for more than 2 batches.

The standard thickness of Mo will be 100 to 299nm.
For thickness 300 to 599nm, the price will be x1.3 the price of standard.
For tickness 600 to 1000nm, the price will be x1.5 the price of standard.

If you want to know the details, please feel free to ask me.


Monday, December 13, 2010

Aluminum Nitride (AlN) for heat sink?

Did you know Aluminum Nitride is well used for "heat sink?"

Aluminum Nitride(AlN) is a good insulator but high in thermal conductivity.
It is very popular for using as "heat sink."

It is also used for PCB boards as well from the same reason.

For high heating energy sources, such as power electric devices or LEDs, AlN plays a big role.

Do you know how Aluminum Nitride is made?

AlN is made by sintering.
The thermal characteristic of AlN is differed by how they were sintered.

These days, the sintering technology for AlN has been drastically advanced.
The thermal conductivity of AlN has been improved very much.

It is very significant to control the process of sintering, however, it is a critical issue for the manufacturer to monitor the distribution of thermal conductivity within the product.

But ordinal methods could NOT evaluate the distribution of AlN in details.

Thermal Microscope (TM3) has a spatial resolution of 3um and able to evaluate the distribution of thermal conductivity of the samples in 2D.

The following is the result of AlN which was measured with TM3.

Aluminum Nitride (AlN): 282 W/mK

We also noticed that the thermal conductivity varies within the sample.
It had a range of 219 to 318 W/mK

For details, please take a look at
Journal of the Ceramic Society of Japan 116[12] 1260-1264 2008

We do testing service for AlN using Thermal Microsope (TM3).
If you are interested, please feel free to contact us.


Thursday, December 9, 2010

New website!

The new website for Thermowave Analyzer is opened!

Please visit the website at

Thank you.